abstracts of technical papers

 2006 AMOS CONFERENCE ABSTRACTS OF TECHNICAL PAPERS Wailea Marriott Resort September 10 – 14, 2006 Maui, Hawaii 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS SSA SYSTEMS AND PROGRAMS Delivering SSA Capabilities to the Warfighter .................................................................................................... 1 Jennifer van Weezendonk, Space Superiority Materiel Wing Technology Division Integrated Multi‐Sensor System for Enhanced Space Surveillance – Design, Engineering, Integration and Tests ..................................................................................................... 1 Shiang Liu, The Aerospace Corporation Proximity Operations for Space Situational Awareness .................................................................................... 1 Tim Carrico and Travis Langster, Analytical Graphics, Inc. Visualizing and Integrating AFSCN Utilization into a Common Operational Picture.................................. 2 Byron Hays, Scitor Corporation Satellite Survivability Module ............................................................................................................................... 3 Patrick Buehler, Ball Aerospace & Technologies Corporation Space Surveillance Network and Analysis Model Performance Improvements ............................................ 4 Albert Butkus, Master Solutions TELESCOPES AND SENSORS The Quest for Precision Ground‐Based Astronomy: The CCD/Transit Instrument with Innovative Instrumentation.................................................................................................................................................... 5 John McGraw, University of New Mexico Unique Baseline Optical Design of the NESSI Survey Telescope ..................................................................... 6 Mark Ackermann, Sandia National Laboratories Naval Prototype Optical Interferometer Upgrade with Light‐Weight Telescopes and Adaptive Optics: A Status Update..................................................................................................................... 6 Sergio Restaino, Naval Research Laboratory All Spherical Catadoptric Gregorian Design for Meter Class Telescopes........................................................ 7 Peter Ceravolo, Ceravolo Optical Systems Advanced Photon Counting Imaging Detectors with 100ps Timing for Astronomical and Space Sensing Applications ................................................................................................................................ 7 Oswald Siegmund, Space Sciences Laboratory, University of California at Berkeley HDVIP HgCdTe and Silicon Detectors and FPAs for Remote Sensing Applications .................................... 8 Arvind DʹSouza, DRS Sensors & Targeting Systems The Development of HWIL Testing Capabilities for Satellite Target Emulation at AEDC........................... 9 Heard Lowry, Arnold Engineering Development Center Lightweight, Active Optics for Space and Near Space....................................................................................... 10 David Wick, Sandia National Laboratories Dynamic Simulation of a Multiple Beam Fourier Telescopy Imaging System .............................................. 11 E. Louis Cuellar, Trex Enterprises Corporation Study of High‐Performance Coronagraphic Techniques ................................................................................... 11 Volker Tolls, Harvard‐Smithsonian Center for Astrophysics ASTRONOMY The Joint Milli‐Arcsecond Pathfinder Survey: Mission Overview ................................................................... 13 Bryan Dorland, U.S. Naval Observatory, Astronomic Satellite Division The Rice University CCD Imager for Gamma‐Ray Burst Studies..................................................................... 13 Ian Smith, Department of Physics and Astronomy, Rice University Improving the Precision and Accuracy of Near Infrared Stellar Photometry and Astrometry by Modeling the Image Formation Process within the Detector.............................................. 14 Kenneth Mighell, National Optical Astronomy Observatory LWIR Hyperspectral and Multispectral Scene Simulation of Mars.................................................................. 14 Steven Richtsmeier, Spectral Sciences, Inc. TABLE OF CONTENTS 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS IMAGING The AEOS Spectral Imaging System ..................................................................................................................... 16 Kenneth Jerkatis, Boeing – SVS Reconstruction of Multi‐Spectral Images from the AEOS Spectral Imaging Sensor ...................................... 16 Travis Blake, Air Force Institute of Technology Wave Front Control and Image Reconstruction Techniques for Imaging Space Objects at Large Zenith Angles ........................................................................................................................................ 16 Michael Roggemann, Michigan Technological University Atmospheric Effects on Spatial Frequency Bounds of Polarimeter Imaging .................................................. 17 David Strong, Air Force Institute of Technology Wideband Hyperspectral Imaging for Space Situational Awareness .............................................................. 17 Ian Robinson, Raytheon Space and Airborne Systems New Fourier‐Based Constraints for Multi‐Frame Blind Deconvolution.......................................................... 18 Douglas Hope, Institute for Astronomy, University of Hawaii Super Drizzle: Applications of Adaptive Kernel Regression Technique in Astronomical Imaging ............ 18 Hiroyuki Takeda, Electrical Engineering, University of California Numerical Estimation of Random Image Shifts Using a Closed‐Form Solution of the Pseudoinverse............................................................................................................................................ 19 Keith Knox, The Boeing Company LASERS Pushing the Envelope: HI‐CLASS Range and Range‐Rate ................................................................................ 21 Paul Konkola, Textron Systems, Maui Operations Fiber Laser Component Testing for Space Qualification Protocol Development ........................................... 21 Suzzanne Falvey, Northrop Grumman Information Technology Telescope Spectrophotometric and Absolute Flux Calibration, and National Security Applications, Using a Tunable Laser on a Satellite.................................................................................................................. 22 Justin Albert, Department of Physics, California Institute of Technology Wavefront Correction on High Repetition Rate, High Energy Laser System ................................................. 23 Zhi Liao, Lawrence Livermore National Laboratory Compact Fiber Laser for 589 nm Laser Guide Star Generation......................................................................... 23 Deanna Pennington, Lawrence Livermore National Laboratory Sodium Guidestar Radiometry Results from the SOR’s 50W Fasor ................................................................. 23 Jack Drummond, Starfire Optical Range, AFRL/DES Adaptive Beam Director for a Tiled Fiber Array: Concept Development, Numerical Modeling and Experimental Design .............................................................................................. 24 Ernst Polnau, Institute for Systems Research, University of Maryland Recent Research at the JPL Optical Communications Telescope Laboratory.................................................. 25 Keith Wilson, Jet Propulsion Laboratory, California Institute of Technology Field Demonstration of an Active Laser Tracking System................................................................................. 25 Vladimir Markov, MetroLaser, Inc. PAN‐STARRS Pan‐STARRS – A New Generation Optical Survey Telescope System............................................................. 27 Nick Kaiser, Institute for Astronomy, University of Hawaii The Pan‐STARRS Telescope #1 – PS1 and the PS1 Science Mission ................................................................. 27 Kenneth Chambers, Institute for Astronomy, University of Hawaii Space Situational Awareness Applications of the PS1 AP Catalog .................................................................. 28 Dave Monet, U.S. Naval Observatory Flagstaff Station TABLE OF CONTENTS 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS The Pan‐STARRS Moving Object Processing System......................................................................................... 28 Robert Jedicke, Institute for Astronomy, University of Hawaii The Design of the Pan‐STARRS Telescope #1...................................................................................................... 28 Jeffrey Morgan, Institute for Astronomy, University of Hawaii Pan‐STARRS PS1 Observatory, Telescope and Instrumentation Control........................................................ 29 Ed Pier, Institute for Astronomy, University of Hawaii Filter Mounting and Mechanism Design for the Pan‐STARRS PS1 Prototype Telescope System ............... 29 Alan Ryan, Institute for Astronomy, University of Hawaii The Pan‐STARRS Imaging Sky Probe................................................................................................................... 30 Ben Granett, Institute for Astronomy, University of Hawaii The Pan‐STARRS u‐Band Imaging Probe............................................................................................................. 30 Klaus Hodapp, Institute for Astronomy, University of Hawaii The Pan‐STARRS Gigapixel Camera..................................................................................................................... 31 John Tonry, Institute for Astronomy, University of Hawaii The Pan‐STARRS PS1 Calibration System ........................................................................................................... 31 John Tonry, Institute for Astronomy, University of Hawaii Pan‐STARRS PS1 GRASP Controller .................................................................................................................... 32 Peter Onaka, Institute for Astronomy, University of Hawaii The Pan‐STARRS PS1 Image Processing Pipeline............................................................................................... 32 Eugene Magnier, Institute for Astronomy, University of Hawaii Pan‐STARRS PS1 Published Science Products Subsystem ................................................................................ 33 James Heasley, Institute for Astronomy, University of Hawaii ADAPTIVE OPTICS The Black Fringe Wavefront Sensor: Real Time Adaptive Optics with Minimum Computation ................ 34 Richard Tansey, Advanced Technology Center, Lockheed Martin Use of a Radial Shear Interferometer as a Self Reference Interferometer in Adaptive Optics ...................... 34 Richard Tansey, Advanced Technology Center, Lockheed Martin Laboratory Demonstration of a Correlation‐Based Adaptive‐Optical System for Wavefront Sensing of Extended Objects........................................................................................................... 35 Troy Rhoadarmer, U.S. Air Force Research Laboratory Packet Switching Networks for Adaptive Optics System.................................................................................. 36 Robert Eager, Boeing LTS Modular Adaptive Optics Testbed for the NPOI ................................................................................................ 36 Jonathan Andrews, Naval Research Laboratory Characterization of the Variability of the Strehl Ratio of Adaptive Optics Point Spread Functions ........... 37 Julian Christou, Center for Adaptive Optics, University of California, Santa Cruz Preliminary Experimental Evidence of Anisotropy of Turbulence at Maui Space Surveillance Site........... 37 Mikhail Belenʹkii, Trex Enterprises Corporation Control System Performance of a Woofer‐Tweeter Adaptive Optics System................................................. 38 Colin Bradley, University of Victoria Hi‐Contrast Coronographic Imager for Adaptive Optics .................................................................................. 39 Klaus Hodapp, Institute for Astronomy, University of Hawaii “Pocket” Deformable Mirror for an Integrated On‐Mirror Adaptive System................................................. 39 Leonid Beresnev, U.S. Army Research Laboratory Design, Modeling, Installation of the MWIR AO System .................................................................................. 40 James Campbell, Trex Enterprises MEMS Deformable Mirrors for Adaptive Optics in Astronomical Imaging................................................... 41 Steven Cornelissen, Boston Micromachines Corporation TABLE OF CONTENTS 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS ORBITAL DEBRIS Recent Results from the ESA Optical Space Debris Survey............................................................................... 42 Thomas Schildknecht, Astronomical Institute, University of Bern Orbit Processing and Analysis of a Geo Class of High Area‐to‐Mass Debris Objects ................................... 42 Thomas Kelecy, Boeing LTS/AMOS Comparison of Orbital Parameters for GEO Debris Predicted by LEGEND and Observed by MODEST: Can Sources of Orbital Debris be Identified?........................................................................... 43 Edwin Barker, National Aeronautics and Space Administration, Johnson Space Center Strategies for Optimizing GEO Debris Search..................................................................................................... 44 Kathryn Poole, Northrop Grumman Corporation Space Debris Optical Observation System in JAXA/IAT ................................................................................... 44 Atsushi Nakajima, Institute of Aerospace Technology, Japan Aerospace Exploration Agency In‐situ Observations of Space Debris at ESA ....................................................................................................... 45 Gerhard Drolshagen, ESA/ESTEC/TEC‐EES (Invited) Reflectivity of NaK Droplets .................................................................................................................................. 46 Carsten Wiedemann, Institute of Aerospace Systems, Technische Universität Braunschweig NON‐RESOLVED OBJECT CHARACTERIZATION The Early Development of Satellite Characterization Capabilities at the Air Force Laboratories ............... 47 John Lambert, The Boeing Company Canadian Surveillance of Space Concept Demonstrator: Photometric Variability of Deep‐Space Objects, Analysis and Interpretation ........................................................................................... 47 Bryce Bennett, Department of Physics, Royal Military College of Canada Harmonic Structure Function ................................................................................................................................ 48 David Dikeman, Lockheed Martin Hawaii Statistical Properties and Analysis of Photometric Signatures of Geos ........................................................... 48 Tamara Payne, Boeing LTS Results of Satellite Brightness Modeling Using Kriging Optimized Interpolation ........................................ 48 Charity Weeden, Canadian Forces, NJ55X Policy and Doctrine MSSS Satellite Categorization Laboratory ........................................................................................................... 49 Ray Deiotte, The Boeing Company AMOS Observations of NASA’s IMAGE Satellite .............................................................................................. 49 Doyle Hall, The Boeing Company Simulated Aging of Spacecraft External Materials on Orbit.............................................................................. 50 Sergei Khatipov, Moscow State Engineering Physics Institute Using Space Weathering Models to Match Observed Spectra to Predicted Spectra ...................................... 50 Michael Guyote, Boeing Comparisons of Ground Truth and Remote Spectral Measurements of the FORMOSAT and ANDE Spacecrafts ........................................................................................................................................ 51 Kira Abercromby, ESCG/Jacobs Sverdrup Satellite Characteristics with uvbyHβCa Photometry........................................................................................ 51 Nancy Hamilton, National Security Agency 3 ‐ 13 μm Spectra of Geosynchronous Satellites.................................................................................................. 52 David Lynch, The Aerospace Corporation Algorithms for Hyperspectral Endmember Extraction and Signature Classification with Morphologial Dendritic Networks ........................................................................................................... 52 Mark Schmalz, Center for Computer Vision and Visualization, University of Florida TABLE OF CONTENTS 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Science Applications of the RULLI Camera: Photon Thrust, General Relativity and the Crab Nebula.......................................................................................................................................................... 53 Douglas Currie, Department of Physics, University of Maryland College Park Hyperspectral H V Polarization Inverse Correlation ......................................................................................... 54 David Maker, Photon Research Associates SATELLITE METRICS Risk Reduction Activities for the Near‐Earth Object Surveillance Satellite Project........................................ 55 Donald Bédard, Defence R&D Canada EOS Space Debris Tracking Using High Power Lasers ...................................................................................... 56 Craig Smith, EOS Space Systems Phoenix Upgrades in Support of Real‐Time Space Object Capture and Handoff at AMOS......................... 56 Dennis Liang, Boeing LTS Proposal for a European Space Surveillance System‐Results of an ESA Study .............................................. 57 Thomas Schildknecht, Astronomical Institute, University of Bern POSTER PRESENTATIONS Large Optical Glass Lenses for ELTs..................................................................................................................... 58 Arnie Bazensky, Schott North America Parallel Particle Swarm Optimization................................................................................................................... 58 Brian Birge, Boeing LTS Statistics of Short Term Seeing at AEOS............................................................................................................... 58 L. William Bradford, The Boeing Company High Performance Computing Software Applications Institute for Space Situational Awareness – Overview ........................................................................................................ 59 Francis Chun, HSAI‐SSA, AFRL/DE Analysis of the Atmospheric Impact on the Analysis of Hyperspectral Imagery .......................................... 59 Joseph Coughlin, Master Solutions The Skygrid Project – A Calibration Star Catalogue for DoD Sensors ............................................................. 60 Stephen Gregory, Boeing LTS Environmental Space Situation Awareness and Joint Space Effects................................................................. 60 Kelly Hand, Air Force Space Command Combining Data from Multiple Telescopes to Improve the Resolution of Imagery Degraded by Atmospheric Turbulence..................................................................................................................................... 60 Douglas Hope, Institute for Astronomy, University of Hawaii Linear Mode Photon Counting LADAR Camera Development for the Ultra‐Sensitive Detector Program ................................................................................................................................................. 61 Michael Jack, Raytheon Vision Systems Observation, Prediction, and Modeling Atmospheric Structure Effects on EO/IR Systems ......................... 61 Michael Kendra, Atmospheric and Environmental Research Observational and Modeling Study of Mesospheric Bores................................................................................ 62 Pamela Loughmiller, School of Electrical and Computer Engineering, Cornell University Space Situation Awareness Integration Office Overview and Spiral 2 Results .............................................. 63 David Newton, Space Systems Architect, Space Situation Awareness Integration Office Accelerating Scientific Computations Using FPGAs .......................................................................................... 63 Oliver Pell, Imperial College London The Effects of Scintillation on Non‐Redundant Aperture Masking Interferometry....................................... 65 Lewis Roberts, The Boeing Company Using Light Curves to Characterize Size and Shape of Pseudo‐Debris ........................................................... 65 Heather Rodriguez, ESCG/Jacobs Sverdrup TABLE OF CONTENTS 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Hawaiian Atmospheric Forecasting Utilizing the Weather Research and Forecast Model .......................... 66 Kevin Roe, Maui High Performance Computing Center Beam Propagation Modeling ................................................................................................................................. 66 Patrick Ryan, Science Applications International Corporation Lightcurve Signatures of Multiple Object Systems in Mutual Orbits .............................................................. 66 Eileen Ryan, Magadalena Ridge Observatory Training and Tactical Operationally Responsive Space Operations ................................................................ 67 Barbara Sorensen, U.S. Air Force Research Laboratory Mobile Tracking Systems Using Large Reflective Telescopes ........................................................................... 68 Kyle Sturzenbecher, Photo‐Sonics Inc. Neutral Density Measurements Using In‐flight Accelerometer Data .............................................................. 69 Byron D. Tapley, University of Texas at Austin, Center for Space Research Impact of Space Weather on Flash Memory Devices.......................................................................................... 69 Scott Teare, Electrical Engineering Department, New Mexico Tech Adaptive Optics Survey of O Stars using AEOS ................................................................................................. 70 Nils Turner, The CHARA Array, c/o Mount Wilson Observatory The Developing Science and Technology List ..................................................................................................... 71 Raymond Wick, Institute for Defense Analyses Using Distributed Sensor Network Architecture to Link Heterogeneous Astronomical Assets.................. 71 Robert White, Los Alamos National Laboratory Structural Analysis of the 0.4 Meter Lightweight CFRP OTA at the NRL ...................................................... 72 Christopher Wilcox, Naval Research Laboratory TABLE OF CONTENTS 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Delivering SSA Capabilities to the Warfighter Maj Jennifer van Weezendonk1, Lt Col Jeffrey Sherk2, Capt Tracie Ryan2, Capt Ryan McGuire2 1
Space Superiority Materiel Wing Technology Division, 2Space & Missiles System Center/SYT The Space Superiority Systems Wing at the Space and Missile Center (SMC/SY) equips US forces with Offensive Counterspace (OCS), Defensive Counterspace (DCS), and Space Situation Awareness (SSA) systems that further enhance space superiority. The Technology Division (SYT) mission is to identify, develop, and transition cutting‐edge technologies to the warfighter. SYT invests in the most relevant technologies for SSA, DCS and OCS that enhance SMC/SY’s portfolio. This presentation will provide an overview of the SMC/SY SSA Technology being worked and highlights several key programs. The presentation will also highlight how the SMC/SY SSA efforts fit into to a Space Superiority Architecture. SYT executes its own Space Control Technology program line and leverages technologies from various DoD and national laboratories, Federally Funded Research and Development Companies, national agencies, industry and academia to accomplish their mission. The portions of the SY FY06 SSA portfolio that will be discussed are: Precision Metrics, Star Sensor Studies, Multi‐mission Deployable Optical System, Intelligent Agent Data Fusion efforts, ESSA ACTD and the GReAT tech demo. Integrated Multi‐Sensor System for Enhanced Space Surveillance – Design, Engineering, Integration and Tests Shiang Liu1, Vladimir B. Markov2, Roberta Ewart3, Doug Craig4 The Aerospace Corporation, 2MetroLaser Inc., 3Air Force Space and Missile Systems Center, Space Superiority Directorate, 4Air Force Research Laboratory, Space Vehicle Directorate 1
Abstract unavailable. Proximity Operations for Space Situational Awareness Spacecraft Rendezvous and Maneuvering using Numerical Simulations and Fuzzy Logic Timothy Carrico1, Travis Langster1, John Carrico2, Alfano3, Salvatore3, Mike Loucks4, David Vallado5 Analytical Graphics, Inc., 2Applied Defense Systems, 3Center for Space Standards and Innovation, 4Space Exploration Engineering, 5Center for Space Standards and Innovation 1
The authors present several spacecraft rendezvous and close proximity maneuvering techniques modeled with a high‐precision numerical integrator using full force models and closed loop control with a Fuzzy Logic intelligent controller to command the engines. The authors document and compare the maneuvers, fuel use, and other parameters. This paper presents an innovative application of an existing capability to design, simulate and analyze proximity maneuvers; already in use for operational satellites performing other maneuvers. The system has been extended to demonstrate the capability to develop closed loop control laws to maneuver spacecraft in close proximity to another, including stand‐off, docking, lunar landing and other operations applicable to space situational awareness, space based surveillance, and SSA SYSTEMS AND PROGRAMS Page 1 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS operational satellite modeling. The fully integrated end‐to‐end trajectory ephemerides are available from the authors in electronic ASCII text by request. The benefits of this system include: •
A realistic physics‐based simulation for the development and validation of control laws. •
A collaborative engineering environment for the design, development and tuning of spacecraft law parameters, sizing actuators (i.e., rocket engines), and sensor suite selection. •
An accurate simulation and visualization to communicate the complexity, criticality, and risk of spacecraft operations. •
A precise mathematical environment for research and development of future spacecraft maneuvering engineering tasks, operational planning and forensic analysis. •
A closed loop, knowledge‐based control example for proximity operations. This proximity operations modeling and simulation environment will provide a valuable adjunct to programs in military space control, space situational awareness and civil space exploration engineering and decision making processes. Visualizing and Integrating AFSCN Utilization into a Common Operational Picture Byron R. Hays1, Andrew M. Carlile1, Troy S. Mitchell2 Scitor Corporation, 250 SCS/SCXI 1
The Department of Defense (DoD) and the 50th Space Network Operations Group Studies and Analysis branch (50th SCS/SCXI), located at Schriever AFB Colorado, face the unique challenge of forecasting the expected near term and future utilization of the Air Force Satellite Control Network (AFSCN). The forecasting timeframe covers the planned load from the current date to ten years out. The various satellite missions, satellite requirements, orbital regions, and ground architecture dynamics provide the model inputs and constraints that are used in generating the forecasted load. The AFSCN is the largest network the Air Force uses to control satellites worldwide. Each day, network personnel perform over 500 scheduled events—from satellite maneuvers to critical data downloads. The Forecasting Objective is to provide leadership with the insights necessary to manage the network today and tomorrow. For both today’s needs and future needs, SCXI develops AFSCN utilization forecasts to optimize the ground system’s coverage and capacity to meet user satellite requirements. SCXI also performs satellite program specific studies to determine network support feasibility. Network Operations Centers
Schriever AFB
Onizuka AFS
Thule Greenland
Oakhanger, AFB
New Hampshire
Vandenberg, AFB
Schriever, AFB
Guam
Hawaii
Diego Gracia
Figure 1 – AFSCN SSA SYSTEMS AND PROGRAMS Page 2 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS STK and STK Scheduler form the core of the tools used by SCXI. To establish this tool suite, we had to evaluate, evolve, and validate both the COTS products and our own developed code and processes. This began with calibrating the network model to emulate the real life scheduling environment of the AFSCN. Multiple STK Scheduler optimizing (de‐confliction) algorithms, including Multi‐Pass, Sequential, Random, and Neural, were evaluated and adjusted to determine applicability to the model and the accuracy of the prediction. Additionally, the scheduling Figure of Merit (FOM), which permits custom weighting of various parameters, was analyzed and tested to achieve the most accurate real life result. With the inherent capabilities of STK and the ability to wrap and automate output, SCXI is now able to visually communicate satellite loads in a manner never seen before in AFSCN management meetings. Scenarios such as regional antenna load stress, satellite missed opportunities, and the overall network “big picture” can be visually displayed in 3D versus the textual and line graph methods used for many years. This is the first step towards an integrated space awareness picture with an operational focus. SCXI is working on taking the visual forecast concept farther and begin fusing multiple sources of data to build a 50 SW Common Operating Picture (COP). The vision is to integrate more effective orbital determination processes, resource outages, current and forecasted satellite mission requirements, and future architectural changes into a real‐time visual status to enable quick and responsive decisions. This COP would be utilized in a Wing Operations Center to provide up to the minute network status on where satellites are, which ground resources are in contact with them, and what resources are down. The ability to quickly absorb and process this data will enhance decision analysis and save valuable time in both day to day operations and wartime scenarios. Satellite Survivability Module Patrick Buehler1, Joshua Smith1, Joseph Keith Farmer2, Darrell Bonn2 1
Ball Aerospace & Technologies Corporation, 2L‐3/Jaycor The Satellite Survivability Module (SSM) is an end‐to‐end, physics‐based, performance prediction model for directed energy engagement of orbiting spacecraft. Two engagement types are currently supported: laser engagement of the focal plane array of an imaging spacecraft; and Radio Frequency (RF) engagement of spacecraft components. For laser engagements, the user creates a spacecraft, its optical system, any protection techniques used by the optical system, a laser threat, and an atmosphere through which the laser will pass. For RF engagements, the user creates a spacecraft (as a set of subsystem components), any protection techniques, and an RF source. SSM then models the engagement and its impact on the spacecraft using four impact levels: degradation, saturation, damage, and destruction. Protection techniques, if employed, will mitigate engagement effects. SSM currently supports several two laser and three RF protection techniques. SSM allows the user to create and implement a variety of “what if” scenarios. Satellites can be placed in a variety of orbits. Threats can be placed anywhere on the Earth. Satellites and threats can be mixed and matched to examine possibilities. Protection techniques for a particular spacecraft can be turned on or off individually; and can be arranged in any order to simulate more complicated protection schemes. Results can be displayed as 2‐D or 3‐D visualizations, or as textual reports. In order to test SSM capabilities, the Ball team used it to model engagement scenarios for a space experiment scheduled for the 2011 time frame. SSA SYSTEMS AND PROGRAMS Page 3 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS SSM was created by Ball Aerospace & Technologies Corp. Systems Engineering Solutions in Albuquerque, New Mexico as an add‐on module for the Satellite Tool Kit (STK). The current version of SSM (1.0) interfaces with STK through the Programmer’s Library (STK/PL). Future versions of SSM will employ STK/Connect to provide the user access to STK functionality. The work is currently funded by the Air Force Research Laboratory, Space Vehicles directorate at Kirtland AFB, New Mexico, under contract number FA9453‐06‐C‐0096. Space Surveillance Network and Analysis Model (SSNAM) Performance Improvements Albert Butkus1, Kevin Roe2, Barbara L Mitchell3, Timothy Payne4 Master Solutions, 2Maui High Performance Computing Center, 3Lockheed Martin, IS&S, 4AFSPC Space Analysis 1
The Space Surveillance Network and Analysis Model (SSNAM) is an AFSPC model which provides the capability to analyze and architect Space Surveillance Network (SSN) Force Structure. To provide these capabilities SSNAM supports two types of simulations: Catalog Maintenance, and Special Events (Launch, On‐Orbit Events, and Breakup). There are many configuration options available with SSNAM: models for all the sensors currently in the SSN to include space based and ground based sensors, hours of operation by sensor, track capacity by sensor, models for sensors yet to be created, user defined weather conditions, NASA catalog growth model including space debris, and solar flux just to name a few. SSNAM is a large software system. It is written in Java, C/C++, and FORTRAN (77 & 95), represents over a million lines of code, and employs a web‐based, load‐sharing architecture to decrease simulation runtime. Catalog Maintenance simulations are both computationally and I/O intensive. A typical Catalog Maintenance simulation (10k to 35k satellites simulated over a 90 day period) will generate over a terabyte of data which, during the course of a simulation, are reduced down to approximately 1.5 gigabytes. Depending on simulation configuration, runtimes can range from 12 to 48 hours on a 16 node, PC network cluster. Due to the high computational demands of SSNAM Catalog Maintenance simulations and the anticipation of transitioning SSNAM to model the maintenance of an SP catalog, the SSNAM system was ported to run on MHPCC platforms in November 2005. This port resulted in at least a three fold increase in performance for all currently parallelized processing in SSNAM. Further modifications to the SSNAM system to better leverage super computing resources are being considered for later releases. This presentation provides a brief overview of the SSNAM application, its web based, load sharing architecture, the effort involved with porting Java and FORTRAN to MHPCC platforms, and the resulting performance gains. SSA SYSTEMS AND PROGRAMS Page 4 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS The Quest for Precision Ground‐Based Astronomy: The CCD/Transit Instrument with Innovative Instrumentation (CTI‐II) John T. McGraw1, Mark R. Ackermann1, Tom Williams1, Peter C. Zimmer1, Walter Gerstle1, G. Fritz Benedict2, Stephen C. Odewahn2, Charles J. Wetterer3, Victor L. Gamiz4, Lt. Eric Golden4, Charles F. Claver5, Dean C. Hines6 1The University of New Mexico, 2The University of Texas at Austin, 3U.S. Air Force Academy, 4AFRL/DE, 5
National Optical Astronomy Observatory, 6Space Science Institute, NESSI/CTI‐II Research Group Precision ground‐based photometric and astrometric measurements enable new astrophysical research programs and new capabilities in faint object detection and characterization for low Earth orbit (LEO) and geosynchronous transfer orbit (GTO) satellites. The CCD/Transit Instrument with Innovative Instrumentation (CTI‐II) is the second generation of a 1.8‐m stationary, meridian pointing telescope fundamentally capable of millimagnitude photometry and milliarcsecond astrometry. The optical design for this telescope is complete, and an innovative focal plane mosaic including real‐time focus feedback is being finalized. We discuss the telescope system design considerations, support instrumentation and calibration techniques that allow this precision, even for measurements made through Earth’s turbulent and turbid atmosphere. Ancillary instrumentation includes optical and structural metrology and monitoring instruments, an atmospheric extinction lidar and a system of cameras capable of providing real‐time extinction measurements. The stationary, fully automated CTI‐II uses the time‐delay and integrate (TDI) readout mode (operated at the sidereal rate) on a mosaic of CCD detectors to nightly generate a five bandpass, 1° wide (declination) image, nominally 120° long (corresponding to observing for an eight‐hour night) strip image of the sky to limiting magnitudes fainter than 21 per bandpass. After one year CTI‐II will have completed observation of a small circle on the sky at a declination of +28°. The CTI‐II data, approximately 200 Gbytes nightly, will enable a large number of astrophysical research programs including Galactic astronomy based upon motions and parallaxes of stars in the solar neighborhood, discovery and synoptic monitoring of variability in the cores of galaxies, and the discovery of targets of opportunity based upon either luminosity variability (e.g. supernovae) or motion (e.g. asteroids). The same database can be used to construct a calibrated, homogeneous photometric and astrometric catalog for northern hemisphere observers. Multi‐night observations are combined to exclude variable stars, enhance the precision of photometry and refine the positions and motions of more than 106 stars distributed in a strip continuous in RA and 1° wide in declination. Multi‐year observations allow production of precision astrometry and photometry, and result in a system of faint photometric and astrometric standard stars useful to northern observers of the sky, including past, current and future large‐scale surveys such as the Sloan Digital Sky Survey, Pan‐STARRS and the Large Synoptic Survey Telescope. The always observable strip of standard stars will be useful for optical sky surveillance systems, in general. CTI‐II is being designed and implemented as part of the Near Earth Space Surveillance Initiative (NESSI), which will link CTI‐II to the Hobby‐Eberly Telescope at McDonald Observatory, a giant special‐purpose spectroscopic telescope capable of obtaining a spectrum of any target of opportunity and synoptically monitoring any object discovered by CTI‐II. NESSI is funded by AFRL. TELESCOPES AND SENSORS Page 5 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Unique Baseline Optical Design of the NESSI Survey Telescope Mark R. Ackermann1, John T. McGraw2, Peter C. Zimmer2, Tom Williams2 1
Sandia National Laboratories, 2University of New Mexico, Physics and Astronomy The NESSI Survey telescope will be the second incarnation of the CCD/Transit Instrument. It is being designed to accomplish precision astronomical measurements, thus requiring excellent image quality and virtually no distortion over an inscribed 1° x 1° scientific field of view. Project constraints such as re‐use of an existing unperforated parabolic f/2.2 primary mirror, and the desire to re‐use much of the existing CTI structure, have forced the design in one direction. Scientific constraints such as the 1.42° field, 60μm/arcsec plate scale, zero focus shift with wavelength, zero distortion and 80% encircled energy within 0.25arcsec spot diameters have further limited remaining design options. After exploring nearly every optical telescope configuration known to man, and several never before imagined, the NESSI Project Team as arrived at a unique optical design that produces a field and images meeting or exceeding all these constraints. The baseline configuration is that of a “bent Cassegrain,” employing a convex hyperbolic secondary, a 45° folding flat and a four lens refractive field group. One unique feature of this design is that all four lenses lie outside the primary aperture, thus introduce no obscuration. A second unique aspect of the design is that the largest lens is only slightly larger than the focal plane array. The field corrector lenses are not large by today’s standards but still large enough to make the availability of glass a serious concern. A number of high performing designs were abandoned when it was learned the glass was either not available or would require a special production. With a little luck, a little insight and a lot of work, we followed the “rugged ways to the stars,” and were able to arrive at a relatively simple Cassegrain design where only one corrector lens had an aspheric surface, a simple parabola, and all four lenses were made of BK7 glass. This design appears to be manufactureable and essentially meets all of the stringent requirements placed upon it. In this paper we present the baseline optical design and describe its associated performance. Naval Prototype Optical Interferometer (NPOI) Upgrade with Light‐Weight Telescopes and Adaptive Optics: A Status Update. Sergio R. Restaino1, Jonathan Andrews1, J. Tom Armstrong1, Ty Martinez1, Christopher Wilcox1, Don Payne2 Naval Research Laboratory, Remote Sensing Div., 2Narrascape Inc. 1
The Naval Prototype Optical Interferometer (NPOI) is the longest baseline at visible wavelengths interferometer in the world. The astronomical capabilities of such an instrument are being exploited and recent results will be presented. NPOI is also the largest optical telescope belonging to the US Department of Defense with a maximum baseline of 435 meter has a resolution that is approximately 181 times the resolution attainable by the Hubble Space Telescope (HST) and 118 times the resolution attainable by the Advanced Electro‐Optical System (AEOS). It is also the only optical interferometer capable of recombining up to six apertures simultaneously. The NPOI is a sparse aperture and its sensitivity is limited by the size of the unit aperture, currently that size is 0.5 meters. In order to increase the overall sensitivity of the instrument a program was started to manufacture larger, 1.4 meter, ultra‐
light telescopes. The lightness of the telescopes requirement is due to the fact that telescopes have to be easily transportable in order to reconfigure the array. For this reason a program was started three years ago to investigate the feasibility of manufacturing Carbon Fiber Reinforced Polymer telescopes, including TELESCOPES AND SENSORS Page 6 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS the optics. In this paper we will present a status report of this part of the program. Furthermore, since the unit apertures are now much larger than r0 there is a need to compensate the aperture with adaptive optics. This paper will present also the status of our adaptive optics system and some of the results attained so far with it. We will discuss the integration program of the larger telescopes into the NPOI and the immediate and longer term plans for this facility. All Spherical Catadoptric Gregorian Design For Meter Class Telescopes Peter Ceravolo Ceravolo Optical Systems An all‐spherical catadioptric Gregorian telescope design suitable for meter class telescopes is described. A group of small lenses is placed at the intermediate focus of the Gregorian system to correct the aberrations of the fast (f/1.5 range) concave spherical primary mirror and concave spherical secondary mirror. The corrective lenses are of simple form and conventional substrate. The system’s performance is diffraction limited in the visible portion of the spectrum and is ideal for narrow angle, broadband CCD imaging. Advanced Photon Counting Imaging Detectors with 100ps timing for Astronomical and Space Sensing Applications Oswald Siegmund1, John Vallerga1, Barry Welsh1, Mike Rabin2, Jeffrey Bloch2 Space Sciences Laboratory, University of California at Berkeley , 2Los Alamos National Laboratory 1
In recent years EAG has implemented a variety of high‐resolution, large format, photon‐counting MCP detectors in space instrumentation for satellite FUSE, GALEX, IMAGE, SOHO, HST‐COS, rocket, and shuttle payloads. Our scheme of choice has been delay line readouts encoding photon event position centroids, by determination of the difference in arrival time of the event charge at the two ends of a distributed resistive‐capacitive (RC) delay line. Our most commonly used delay line configuration is the cross delay line (XDL). In its simplest form the delay‐line encoding electronics consists of a fast amplifier for each end of the delay line, followed by time‐to‐digital converters (TDCʹs). We have achieved resolutions of < 25 μm in tests over 65 mm x 65 mm (3k x3k resolution elements) with excellent linearity. Using high speed TDC’s, we have been able to encode event positions for random photon rates of ~1 MHz, while time tagging events using the MCP output signal to better than 100 ps. The unique ability to record photon X,Y,T high fidelity information has advantages over “frame driven” recording devices for some important applications. For example we have built open face and sealed tube cross delay line detectors used for biological fluorescence lifetime imaging, observation of flare stars, orbital satellites and space debris with the GALEX satellite, and time resolved imaging of the Crab Pulsar with a telescope as small as 1m. Although microchannel plate delay line detectors meet many of the imaging and timing demands of various applications, they have limitations. The relatively high gain (107) reduces lifetime and local counting rate, and the fixed delay (10’s of ns) makes multiple simultaneous event recording problematic. To overcome these limitations we have begun development of cross strip readout anodes for microchannel plate detectors. The cross strip (XS) anode is a coarse (~0.5 mm) multi‐layer metal and ceramic pattern of crossed fingers on an alumina substrate. The charge cloud is matched to the anode TELESCOPES AND SENSORS Page 7 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS period so that it is collected on several neighboring fingers to ensure an accurate event charge centroid can be determined. Each finger of the anode is connected to a low noise charge sensitive amplifier and followed by subsequent A/D conversion of individual strip charge values and a hardware centroid determination of better than 1/100 of a strip are possible. Recently we have commissioned a full 32 x 32 mm XS open face laboratory detector and demonstrated excellent resolution (<6 μm FWHM, ~5k x 5k resolution) using low MCP gain (<5 x 105) thus increasing the MCP local counting rate capacity and overall lifetime of the detector system. In collaboration with Los Alamos National Laboratory, NASA and NSF we are developing high rate (>107 Hz) XS encoding electronics that will encode temporally simultaneous events (non spatially overlapping). Sealed tube XS detectors with GaAs and other photocathodes are also under development to increase detection efficiency and extend the sensitivity range. This type of sensor could be a significant enabling technology for several important applications, including airborne and space situational awareness, high‐speed adaptive optics (by increasing the SNR and speed in the control loop), astronomy of transient and time‐variable sources, optical metrology, and secure quantum communication (as a receiver of cryptographic keys for three‐dimensional imaging), single‐molecule fluorescence lifetime microscopy (simultaneously tracking and measuring ~1000 molecules), optical/NIR LIDAR, hybrid mass spectrometry and optical night‐time/reconnaissance (LANL‐
ASPIRE). HDVIP HgCdTe and Silicon Detectors and FPAs for Remote Sensing Applications A. I. D’Souza1, M. G. Stapelbroek1, E. Atkins1, H. Hogue1, J. Reekstin1, M. R. Skokan2, M. A. Kinch2, P. K. Liao2, M. J. Ohlson2, P. J. Ronci2, T. Teherani2, H. D. Shih2 1
DRS Sensors & Targeting Systems, 2DRS Infrared Technologies Photon detectors and focal plane arrays (FPAs) are fabricated from HgCdTe and silicon in many varieties. DRS LPE‐grown SWIR, MWIR and LWIR HgCdTe material fabricated in the High‐Density Vertically Integrated Photodiode (HDVIP) architecture has been focused primarily on high background systems applications with great success. Remote sensing applications, however, may need to operate under both high and low background conditions. HgCdTe HDVIP FPAs have been measured under a variety of flux conditions and at several operating temperatures. In addition, DRS manufactures silicon detectors and FPAs that cover the spectral range from visible to the very‐long‐wavelength infrared (VLWIR). Detectors are manufactured that exhibit high internal gain to allow photon counting over this broad spectral range. Large‐format, VLWIR FPAs based on doped‐silicon Blocked‐Impurity‐Band (BIB) detectors have been developed. FPAs with Si:As BIB arrays have been made in a variety of pixel formats (up to 10242) and have been optimized for low, moderate, and high infrared backgrounds. DRS uses LPE‐grown SWIR, MWIR and LWIR HgCdTe material to fabricate High‐Density Vertically Integrated Photodiode (HDVIP) architecture detectors. 2.5 μm, 5.3 μm and 10.5 μm cutoff detectors have been fabricated into linear arrays as technology demonstrations targeting remote sensing programs. This paper presents 320 x 6 array configuration technology demonstrations’ performance of HDVIP HgCdTe detectors and single detector noise data. The single detector data are acquired from within the 320 x 6 array. Within the arrays, the detector size is 40 μm x 50 μm. The MWIR detector array has a mean quantum efficiency of 89.2 % with a standard deviation to mean ratio, σ/μ = 1.51 %. The integration time for the focal plane array (FPA) measurements is 1.76 ms with a frame rate of 557.7 Hz. Operability values exceeding 99.5 % have been obtained. The LWIR arrays measured at 60 K had high operability with only ~ 3 % of the detectors having out of family response. TELESCOPES AND SENSORS Page 8 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Noise was measured at 60 K and 50 mV reverse bias on a column of 320 diodes from a 320 x 6 LWIR array. Integration time for the measurement was 1.76 ms. Output voltage for the detectors was sampled every 100th frame. 32,768 frames of time series data were collected for a total record length of 98 minutes. The frame average for a number of detectors was subtracted from each detector to correct for temperature drift and any common‐mode noise. The corrected time series data was Fourier transformed to obtain the noise spectral density as a function of frequency. Since the total time for collecting the 32,768 time data series points is 98.0 minutes, the minimum frequency is 170 μHz. A least squares fit of the form (A/f + B) is made to the noise spectral density data to extract coefficients A and B that relate to the 1/f and white noise of the detector respectively. In addition noise measurements were also acquired on columns of SWIR detectors. Measurements were made under illuminated conditions at 4 mV and 50 mV reverse bias and under dark conditions at 50 mV reverse bias. The total collection time for the SWIR detectors was 47.7 minutes. The detectors are white noise limited down to ~ 10 mHz under dark conditions and down to ~ 100 mHz under illuminated conditions. In addition, 256 x 256 MWIR arrays have been measured at 78K. Operability values exceeding 99.5 % have been obtained. Data will also be presented on a variety of silicon products. Arsenic‐doped silicon (Si:As) BIB detector arrays with photon response out to about 28 μm, and Antimony‐doped silicon (Si:Sb) BIB arrays having response to wavelengths > 40 μm have been demonstrated. Avalanche processes in Si:As at low temperatures (~ 8 K) have led to two unique solid‐state photon‐counting detectors adapted to infrared and visible wavelengths. The infrared device is the solid‐state photomultiplier (SSPM) capable of counting VLWIR photons (λ ≤ 28 μm) with high quantum efficiency. A related device optimized for the visible spectral region is the visible‐light photon counter (VLPC). The VLPC is a nearly ideal device for detection of small bunches of photons with excellent time resolution. Finally, DRS makes imaging arrays of pin‐diodes utilizing the intrinsic silicon photoresponse to provide high performance over the 0.4 – 1.0 μm spectral range operating near room temperature. pin‐diode arrays are particularly attractive as an alternative to charge‐coupled devices (CCDs) for space applications where radiation hardening is needed. The Development of HWIL Testing Capabilities for Satellite Target Emulation at AEDC H. S. Lowry1, D. H. Crider1, J. M. Burns2, Rhoe Thompson3, G. C. Goldsmith II4, W. J. Sholes5 Aerospace Testing Alliance, Arnold Engineering Development Center, 2AEDC/DOS, 3Kinetic Kill Vehicle Hardware‐in‐the‐
loop Simulator Facility, AFRL/MNGG, 4Guided Weapons Evaluation Facility, 46th Test Wing/TSWH, 5AMRDEC 1
Programs involved in Space Situational Awareness (SSA) need the capability to test satellite sensors in a Hardware‐in‐the‐Loop (HWIL) environment. Testing in a ground system avoids the significant cost of on‐orbit test targets and the resulting issues such as debris mitigation, and in‐space testing implications. The space sensor test facilities at AEDC consist of cryo‐vacuum chambers that have been developed to project simulated targets to air‐borne, space‐borne, and ballistic platforms. The 7V chamber performs calibration and characterization of surveillance and seeker systems, as well as some mission simulation. The 10V chamber is being upgraded to provide real‐time target simulation during the detection, acquisition, discrimination, and terminal phases of a seeker mission. The objective of the Satellite Emulation project is to upgrade this existing capability to support the ability to discern and track other satellites and orbital debris in a HWIL capability. It would provide a baseline for realistic testing of satellite surveillance sensors, which would be operated in a controlled environment. Many sensor functions could be tested, including scene recognition and maneuvering control software, using real interceptor hardware and software. Statistically significant and repeatable datasets produced by the satellite emulation system can be acquired during such test and saved for further analysis. In TELESCOPES AND SENSORS Page 9 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS addition, the robustness of the discrimination and tracking algorithms can be investigated by a parametric analysis using slightly different scenarios; this will be used to determine critical points where a sensor system might fail. The radiometric characteristics of satellites are expected to be similar to the targets and decoys that make up a typical interceptor mission scenario, since they are near ambient temperature. Their spectral reflectivity, emissivity, and shape must also be considered, but the projection systems employed in the 7V and 10V chambers should be capable of providing the simulation of satellites as well. There may also be a need for greater radiometric intensity or shorter time response. An appropriate satellite model is integral to the scene generation process to meet the requirements of SSA programs. The Kinetic Kill Vehicle Hardware‐in‐the‐Loop Simulator (KHILS) facility and the Guided Weapons Evaluation Facility (GWEF), both at Eglin Air Force Base, FL are assisting in developing the scene projection hardware, based on their significant test experience using resistive emitter arrays to test interceptors in a real‐time environment. Army Aviation and Missile Research & Development Command (AMRDEC) will develop the Scene Generation System for the real‐time mission simulation. Lightweight, Active Optics for Space and Near Space David V. Wick1, Brett E. Bagwell1, Ty Martinez2, Don M. Payne3, Sergio R. Restaino2, Robert Romeo4 Sandia National Laboratories, 2Naval Research Laboratory, 3Narrascape, Inc., 4Composite Mirror Applications, Inc. 1
Size, weight, and a lack of adaptability currently hinder the effectiveness of conventional imaging sensors in a number of military applications, including space‐based space situational awareness (SSA), intelligence, surveillance, and reconnaissance (ISR), and missile tracking. The development of sensors that are smaller, lighter weight, adaptive, and use less power is critical for the success of future military initiatives. Threat detection systems need the flexibility of a wide FOV for surveillance and situational awareness while simultaneously maintaining high‐resolution for target identification and precision tracking from a single, nonmechanical imaging system. Sandia National Laboratories, the Naval Research Laboratory, Narrascape, Inc., and Composite Mirror Applications, Inc. are at the forefront of active optics research, leading the development of active systems for foveated imaging, nonmechanical zoom, phase diversity, and actively enhanced multi‐spectral imaging. Increasing the field‐of‐view, spatial resolution, spectral capability and system magnification have all been demonstrated with active optics. Adding active components to existing systems should significantly enhance capability in a number of military applications, including night vision, remote sensing and surveillance, chemical/biological detection, and large aperture, space‐based systems. Deployment costs of large aperture systems in space or near‐space are directly related to the weight of the system. In order to minimize the weight of conventional primary mirrors and simultaneously achieve an agile system that is capable of true optical zoom without macroscopic moving parts, we are proposing a revolutionary alternative to conventional telescopes where moving lenses/mirrors and gimbals are replaced with lightweight carbon fiber reinforced polymer (CFRP) variable radius‐of‐curvature mirrors (VRMs) and MEMS deformable mirrors (DMs). CFRP and MEMS DMs can provide a variable effective focal length, generating the flexibility in system magnification that is normally accomplished with mechanical motion. By simply adjusting the actuation of the CFRP VRM and MEMS DM in concert, the focal lengths of these adjustable elements, and thus the magnification of the whole system, can be changed without macroscopic moving parts on a millisecond time scale. TELESCOPES AND SENSORS Page 10 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Dynamic Simulation of a Multiple Beam Fourier Telescopy Imaging System James Stapp1, E. Louis Cuellar1, Brett Spivey2, Laurence Chen1, Lisandro Leon1, Kevin Hughes1, Dave Sandler1 Trex Enterprises Corporation, 2Quexta 1
A detailed simulation has been developed to model a high resolution active imaging LEO satellite system currently being designed under the Satellite Active Imaging National Testbed (SAINT) program. This imaging system is based upon Fourier Telescopy, which uses multiple coherent laser beams that illuminate a target with a fringe pattern that sweeps across it due to a known frequency differences between the beams. In this way the target spatial frequency components are encoded in the temporal signal that is reflected from the coherently illuminated target. The software simulation program models both the dynamic reconfiguration of the continuous‐wave transmitter laser beams and the atmospheric uplink / downlink turbulence effects. In addition, accurate modeling of the changing satellite target aspect over the imaging period is included in the simulation to properly model the received time‐
dependent reflected intensity received from the satellite target on the ground. A novel reconstructor has been developed that compensates for atmospheric phase fluctuations affecting the large number of beams transmitted simultaneously (10 – 20 beams). A new type of global phase closure has been developed, which allows image reconstruction from the time history of measured total reflected intensity from the target. The reconstruction algorithm also solves for hundreds of image Fourier components simultaneously, permitting rapid reconstruction of the image. Study of High‐Performance Coronagraphic Techniques Volker Tolls1, Michael Aziz2, Robert A. Gonsalves3, Sylvain Korzennik1, Antoinne Labeyrie4, Richard Lyon5, Gary Melnick1, Steve Somerstein6, Gopal Vasudevan6, Robert Woodruff6 Harvard‐Smithsonian Center for Astrophysics, 2Harvard University, 3Tufts University, 4Observatoire de Haute‐Provence, 5Goddard Space Flight Center, 6Lockheed‐Martin Corporation 1
Direct imaging of extra‐solar planets is important for determining the properties of individual planets, for studying multi‐planet systems, and for observing the spatial structure of debris disks. Obtaining spectra of extra‐solar planets enables us to constrain the composition of planetary atmospheres and surfaces, their climates, and their rotation periods. The techniques required to isolate and detect an extra‐solar planet next to its host star are quite challenging and require significant improvement. SAO has set up a testbed to study coronagraphic techniques, starting with Labeyrieʹs multi‐step speckle reduction technique. The testbed consists of a classical coronagraph with high precision optics. A telescope is simulated by a 2 inch spherical mirror with lambda/1000 surface quality. The focal length (1 meter) of this mirror was chosen that spherical aberration can be neglected. A spatially‐filtered laser simulates the host star and an optional attenuated second laser simulates the planet. As an additional option, we can incorporate apodizing masks to further improve the performance of the coronagraph. The output signal of the coronagraph is fed into a single Labeyrie correction stage. It consists of a mirror to relay the light onto a 140‐element MEMS deformable mirror (DM) for the phase correction. The reflected light is then focused onto a second occulter to block most of the speckle light and finally imaged onto a CCD. The phase correction function and, thus, the drive signal for the DM, is derived from images taken in and slightly out of the focal plane using phase diversity. The expected performance improvement is about one order TELESCOPES AND SENSORS Page 11 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS of magnitude. An advanced concept utilizing phase and amplitude correction promises an even higher degree of speckle light suppression. In addition, we are using the testbed to characterize occulter masks developed in collaboration with Harvard University and Lockheed Martin Corp. At Harvard University we are developing a method to shape occulter masks out of dye‐doped PMMA using a focused ion beam (FIB) system. Using dye‐doped PMMA should enable us to manufacture masks working at any wavelength from the visible to the near‐
infrared. It should also be possible to manufacture masks for the IR if a suitable mask material can be found. In order to test the absorption profile of these masks, we are developing a high‐precision mask scanner. This work is supported by NASA through grant NNG04GC57G, SAO IR&D funding, NSF REU program and Harvard College. TELESCOPES AND SENSORS Page 12 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS The Joint Milli‐Arcsecond Pathfinder Survey (J‐MAPS): Mission Overview B. Dorland, R. Gaume, N. Zacharias, D. Monet, K. Johnston U.S. Naval Observatory We describe the Joint Milli‐Arcsecond Pathfinder Survey (J‐MAPS) at the unclassified level. J‐MAPS is a space‐based, all‐sky astrometric and photometric survey from 2nd through 15th magnitude with a 2010 launch date goal. The instrument consists of a 15‐cm telescope, a large (64 megapixel) active pixel sensor focal plane, and associated processing electronics and is carried aboard a microsatellite bus in a 900‐km, sun‐synchronous low earth orbit. In addition to presenting a mission overview, we will discuss the unclassified applications of the mission and its data products. The primary mission goal for J‐MAPS is the generation of a 1‐milliarcsecond (mas) all‐sky astrometric catalog for the 2010 epoch in support DoD space platform precise orientation needs for the next decade and later. The resultant optical reference grid will be available for all ground‐ and space‐
based optical SSA sensors, with a density of >100 stars per square degree and a resolution of 20 cm at GEO. In addition, J‐MAPS will serve as a pathfinder for new technology in support of future space missions, including the very large format detector, the onboard processing electronics, and next generation space‐based GPS‐technology. We also discuss the astronomy and astrophysics applications of J‐MAPS. A 1‐mas (or better) all‐sky survey through approximately 15th magnitude will have a tremendous impact on our current understanding of the galaxy and stellar astrophysics. J‐MAPS science topics include: a kinematic and photometric exploration of the nearest star forming regions and associations; an understanding of the dynamics and membership of nearby open clusters; a survey of nearby stars that addresses the 130 missing systems within 10 pc; recalibration of the cosmic distance scale via distances to nearby clusters and the period‐luminosity relationship using high accuracy proper motion (Hipparcos and J‐MAPS positions and a twenty year baseline) and parallax measurements; discovery of giant planets and brown dwarfs orbiting nearby stars; kinematic detection of galactic cannibalism and mergers in the Milky Way; and discovery of low‐mass black holes and neutron stars in astrometric binaries. The Rice University CCD Imager for Gamma‐Ray Burst Studies Ian A. Smith1, Reginald J. Dufour1, Edison P. Liang1, Jeffrey M. Silverman2, Larry C. Hardin3, Robert D. Forgey3, Mark A. Skinner4, Andrew Alday4, Carl Akerlof5, Heather Swan5, Tim McKay5, Eli Rykoff5, Sarah Yost5 1
Rice University, Department of Physics and Astronomy, 2University of California at Berkley, Astronomy Department, 3Hardin Optical Company, 4Boeing LTS, Inc., 5University of Michigan Gamma‐Ray Bursts (GRBs) are the largest explosions in the Universe since the Big Bang. The ability to study GRBs has significantly improved thanks to the rapid localization of bursts by the Swift satellite. The AEOS 3.63‐m telescope is filling important gaps in the capabilities of the world‐wide network of ground‐
based observatories doing GRB follow‐up observations. Here we will summarize the status of the field and the results obtained to date by the Rice University CCD imager (RUCCD), one of the instruments used by the MARGE collaboration to study burst afterglows. The RUCCD currently operates in Coude room 6 of the AEOS telescope. It has eight filter wheel slots, and can perform imaging photometry, spectroscopy, and polarimetry, using exposure times as short as 20 milliseconds. The CCD has a high quality and uniformity, and the focus is good across the whole field of view. Spectroscopy is performed ASTRONOMY Page 13 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS using an imaging‐grism and/or imaging‐grating system rather than a slit spectrometer. This disperses the spectra of all the sources in the field of view. During the times it is installed in the Coude room, the RUCCD is thermoelectrically cooled, and is in a permanent state of readiness for making observations. Improving the Precision and Accuracy of Near Infrared Stellar Photometry and Astrometry by Modeling the Image Formation Process within the Detector. Kenneth J. Mighell National Optical Astronomy Observatory Current infrared detector technology can produce imagers with non‐uniform intrapixel response functions. Cameras based on such detectors can have large systematic errors in the measurement of the total stellar flux. This problem can be mitigated by oversampling the stellar image, but many near infrared cameras are undersampled in order to achieve a large field of view. The combination of undersampling stellar images with non‐uniform detectors is currently diminishing the science return of some infrared imagers onboard the Hubble and Spitzer Space Telescopes. Large intrapixel quantum efficiency variations can also cause significant systematic position measurement errors. Although the recorded flux and position of point sources is corrupted by using detectors with non‐uniform intrapixel response functions, it is still possible to achieve excellent stellar photometry and astrometry — if the image formation process inside the detector is accurately modeled. A practical demonstration of how the precision and accuracy of near infrared stellar photometry and astrometry can be significantly improved is provided by a detailed analysis of stellar observations obtained with Spitzer’s Infrared Array Camera (IRAC) instrument. LWIR Hyperspectral and Multispectral Scene Simulation of Mars Steven Richtsmeier1, Robert Sundberg1, Raymond Haren2, Frank O. Clark3 1
Spectral Sciences, Inc., 2AFRL/SNJT, 3AFRL/VSBT Full optical spectrum (UV to LWIR) hyperspectral scene simulation provides an accurate, robust, and efficient means for algorithm validation and sensor design trade studies. This paper reviews the development of a first‐principles, high‐fidelity HSI/MSI image simulation capability, dubbed MCScene, which is based on a Direct Simulation Monte Carlo techniques and demonstrates how the model can be used for sensor design trade studies. Basic features of the model will be discussed and illustrated with a spectral simulation for a prototype hyperspectral sensor. Sample calculations presented in this paper include long wave infrared spectrum simulations for a region of Mars under varying solar illuminations and atmospheric conditions. Source information for simulations will be based on mission data where available. Such simulations can be important for gauging the effects of the Martian atmosphere on mineral determination by orbiting multispectral imagers, for example. MCScene incorporates all optical effects important for solar‐illuminated and thermal scenes, including molecular and aerosol scattering, absorption and emission, surface scattering and emission with material‐
dependent bidirectional reflectance distribution functions (BRDFs), multiple scattering events, surface adjacency effects, and scattering, emission and shading by clouds, for arbitrary solar illumination and sensor viewing geometries. The “world” of the simulation is a cube, nominally 50 km on a side that encloses a user‐definable atmosphere containing molecular species, aerosols, and clouds, and a terrain representing the ground. The sensor spatial and spectral resolution, its location, and the viewing angle ASTRONOMY Page 14 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS are also specified. The field‐of‐view (FOV) is a finely gridded inner region within the 50 km x 50 km ground area; nominally, it is a 10 km square gridded with 1m2 surface pixels. The technique supports surface facets with arbitrary elevations and normals. A particular strength of MCScene is that a simulation can be data driven. Terrain information can be imported from USGS digital elevation maps or other topographical maps. Surface reflectance or emissivity/temperature maps can be derived from collected imagery, thus incorporating natural spectral and spatial texturing into a simulation. ASTRONOMY Page 15 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS The AEOS Spectral Imaging System Kenneth J. Jerkatis Boeing‐SVS, Inc. Abstract unavailable. Reconstruction of Multi‐Spectral Images from the AEOS Spectral Imaging Sensor Maj Travis Blake1, Lt Col Matthew Goda1, Dr. Stephen Cain1, Kenneth J. Jerkatis2 Air Force Institute of Technology, 2Boeing‐SVS, Inc. 1
Spectral images of terrestial objects as provided a wealth of information beyond the tradidtional data provided in a panchromatic image. What has proven to be successful for terrestial applications, can also be applied to images of objects in space. This research expands on previous work discussing the image processing for data collected by the new AEOS Spectral Imaging Sensor (ASIS). ASIS uses broadband filters to collect AO compensated spectral images of astronomical objects and satellites. The use of the broadband filters spectrally blurs the images collected by ASIS. A post‐processing algorithm called Model‐Based Spectral Image Reconstruction (MBSIR) can simultaneously remove much of the spatial and spectral blurring in the sensor. This paper will start by briefly reviewing the development of the MBSIR algorithm. The paper will then show the benefit of the post‐processing algorithm on data collected in a laboratory set‐up. A spectral source was imaged with the same filter, and therefore the same spectral blurring, as those used in ASIS. The results show that the spectral features in the source are not resolvable before applying the MBSIR algorithm and are resolvable after applying the algorithm to the data. Finally, the algorithm is applied to astronomical data collected with ASIS. Wave Front Control and Image Reconstruction Techniques for Imaging Space Objects at Large Zenith Angles Michael C. Roggemann, Glen Archer, Grant Soehnel, Timothy J. Schulz Michigan Technological University Increasing the volume of space which can be monitored for space situational awareness activities requires the ability to form useful images of objects at larger zenith angles, perhaps approaching 70 to 80 degrees. At these zenith angles the atmospheric seeing conditions, as characterized by the Fried parameter, the isoplanatic angle, and the variance of the log amplitude fluctuations, are extremely unfavorable for imaging. In this paper we provide an analysis of the expected seeing conditions in this environment, and discuss our approach to wave front sensing and turbulence‐induced aberration control. A hybrid imaging technique is used in which adaptive optics images are post processed. An expectation maximization algorithm is used to post process the images to remove residual blur. IMAGING Page 16 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Atmospheric Effects on Spatial Frequency Bounds of Polarimeter Imaging Maj David M. Strong Air Force Institute of Technology The intent of this paper is to extend a previously developed statistical model of a polarimetric sensor to include atmospheric effects on the spatial frequency bound. Initial estimates of the spatial frequency resolution are attained through calculation of the Cramer‐Rao lower bound for a two‐channel polarimeter in a vacuum. The definition of maximum spatial frequency resolution for this research is when the highest spatial frequencies observed just meet the noise floor. Previous results for the model in a vacuum showed that the spatial resolution bound is lowered as the degree of polarization in the image is varied from 0 to 1. Before pursuing a blind deconvolution algorithm for a polarimeter it is important to understand the impact of atmospheric effects on the spatial frequency bound. The model used for the polarimeter imaging system is an ideal two‐channel polarimeter with an output of two images of orthogonal polarizations. Models of the atmosphere with various amounts of turbulence are then added to the polarimeter imaging system model to determine the impact on the spatial frequency bound. The number of Zernike coefficients used to model the atmospheric distortions and their impact on the spatial frequency bound is also explored. Additionally, the impact on the bound through the use of a simulated adaptive optic system to reduce the atmospheric turbulence effect on the polarimeter images is shown. The data produced by the developed models is then used to determine the potential for developing new algorithms to improve existing polarimeter imaging capabilities. Wideband Hyperspectral Imaging for Space Situational Awareness Ian S. Robinson1, Alan M. Klier2 1
Raytheon Space and Airborne Systems, 2Photon Research Associates Wideband hyperspectral imaging (WHSI) systems collect simultaneous spectral and spatial imagery across a broad spectrum that includes the visible/near infrared (VNIR), short‐wave infrared (SWIR), mid‐
wave infrared (MWIR), and long‐wave infrared (LWIR) regimes. These passive optical systems capture reflected sunlight and thermal emissions from targets enabling the characterization of surface material, thermal properties, propellants, and gaseous emissions when targets are sunlit or in shadow. WHSI systems can provide imagery with fine spatial detail but do not require this fine spatial resolution to characterize targets. It has been shown previously that multi‐color photometry using distinct channels in the VNIR part of the spectrum can be used to identify objects that are similar to one another and perform some non‐resolved object characterization (NROC). Wideband HSI systems collect a much richer signature from each object with the potential to fingerprint and identify specific space objects smaller than one pixel. WHSI provides unique information on the properties of space objects. Its ability to characterize objects smaller than a pixel is extremely valuable in developing situational awareness of targets at GEO, MEO, and HEO. WHSI can be deployed with cost‐efficient, small aperture telescopes or be used as adjuncts to existing and planned assets. This paper will describe the utility and capabilities of ground‐based and space‐based WHSI systems including rapid identification and characterization of space objects, mitigation of interference from the atmosphere, separation of glints from diffuse signatures, determination of status of space objects, and gauging aging effects. IMAGING Page 17 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS New Fourier‐Based Constraints for Multi‐Frame Blind Deconvolution Douglas Hope1, Stuart M. Jefferies1, 2 Institute for Astronomy, University of Hawaii, 2Steward Observatory, University of Arizona 1
An important problem in imaging is the inverse imaging problem, i.e. given a noisy blurred image of an object and knowledge about the imaging system, obtain a high‐fidelity estimate of the object. When the image is formed under isoplanatic conditions, the image can be modeled as a convolution of the object intensity distribution and the point‐spread‐function (PSF) of the imaging system. In practice, the PSFs are unknown or poorly known, so one must estimate both the object and the PSF simultaneously, a problem known as multi‐frame blind deconvolution (MFBD)1. An important requirement for solving the MFBD problem is the use of prior information about the object, the instrumentation and the physics of the observing conditions. Examples of such information include a positivity constraint on the object, a constraint on its spatial extent (commonly referred to as support), and any partial knowledge of the PSF, possibly obtained from a wave‐front sensor. All such information is pertinent and should be used to constrain the solution space that must be searched by the algorithm We propose new constraints for the MFBD restoration of large ensembles of atmospherically degraded imagery. These constraints, defined in the Fourier domain, essentially restrict the number of spatial frequencies in the object and PSF estimates. A natural outcome of applying this spectral support is a robust regularization method that greatly improves the estimates of both the object and PSFs. We present a method for extracting spectral supports from data and show how to implement them in two different cases of MFBD, 1) images where only part of the object falls on the detector and 2) images where the object falls fully on the detector. 1 T.G. Stockham, Jr. T.M. Cannon and R.B. Ingebretson, Proc. IEEE, 63, 678 (1975)
Super‐Drizzle: Applications of Adaptive Kernel Regression Technique in Astronomical Imaging Hiroyuki Takeda1, Sina Farsiu1, Julian Christou2, Peyman Milanfar1 Electrical Engineering Department, University of California, 2Center for Adaptive Optics, University of California 1
The drizzle algorithm is a widely used tool for image enhancement in the astronomical literature. For example a very popular implementation of this method, as studied by Frutcher and Hook [2001], has been used to fuse, denoise, and increase the spatial resolution of the images captured by the Hubble Space Telescope. However, the drizzle algorithm is an ad‐hoc method, equivalent to an adaptive “linear” filter, insensitive to the (pixel) values of data, which limits its performance. To improve the performance of the drizzle algorithm, we make contact with the field of non‐parametric statistics and generalize the tools and results for use in image processing and reconstruction. In contrast to the parametric methods, which rely on a specific model of the signal of interest, non‐parametric methods rely on the data itself to dictate the structure of the model, in which case this implicit model is referred to as a regression function. We promote the use and improve upon a class of non‐parametric methods called kernel regression. In this paper, we introduce new aspects of the Kernel Regression to the astronomy science community. The novelties of this paper include IMAGING Page 18 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS 1.
We exploit the kernel regression framework to justify a powerful variation of the drizzle algorithm with superior performance, applicable to both regularly and irregularly sampled data. 2.
Unlike the drizzle algorithm, the effective size and shape of the kernel (window) in the proposed method are adapted locally not only to the spatial sampling density of the data, but also to the actual (measured pixel) values of those samples. Such novel data‐adaptive implementation of the drizzle algorithm is especially suitable for reconstructing images with sharp edges 3.
The proposed method is applicable to both single frame and multi‐frame processing scenarios, and is equally effective for both oversampled and undersampled images. 4.
The proposed method takes advantage of a generic model that is optimal for reconstructing images contaminated with different noise models, including additive Gaussian, Laplacian, and Salt & Pepper. Experiments on simulated and real data show diverse applications and the superiority of the proposed adaptive technique with respect to the state of the art methods in the literature (including the drizzle algorithm, the bilateral filter and wavelet‐based methods). We show that the proposed algorithm not only visually and numerically (Peak Signal to Noise Ratio comparison) improves the quality of reconstruction, but also due to its non‐parametric structure will result in images that are faithful with respect to the photometric properties of the original (ideal) image. Numerical Estimation of Random Image Shifts Using a Closed‐Form Solution of the Pseudoinverse Keith T. Knox, Charles E. Mannix The Boeing Company Short‐exposure images of stars and other unresolved objects appear as speckle patterns that randomly move across the image. These random patterns and motion are induced by an accumulated random phase disturbance caused by the light traveling through the time‐varying atmosphere. Larger phase disturbances are responsible for the random motion of the speckle patterns, while smaller phase disturbances define details of the individual speckles. A smoother appearance of the speckle images is possible by estimating the amount of random motion between speckle images and re‐centering the individual images. This is particularly useful when several frames are averaged together to increase the signal‐to‐noise ratio. By re‐centering the individual images before averaging, blur from the random motion of the speckle patterns is reduced and fainter details in the averaged image can be detected. The problem then becomes how to estimate the amount of frame‐to‐frame random motion. One method is to perform the cross‐correlation between the first frame and all other frames in an image sequence. The shift in the peak in this correlation function indicates the difference in positions of the images in the two frames. Re‐centering all but the first of the frames removes a large amount of the random motion. The problem is that the shift in the cross‐correlation peak is measured in an integer number of pixels and this lack of precision leaves a significant amount of the random motion intact. One innovation to be described in this talk is the fact that there is nothing unique about the first frame in the sequence. Any frame in the sequence could be used as the reference from which the differences in location of all the other images are measured. In fact, one can measure the differences in position for all independent pairs of frames in the image sequence. This provides a combinatorially large number of IMAGING Page 19 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS measurements compared to the number of image frames, or shifts. Since the number of measurements is much larger than the number of variables, this problem is significantly over‐determined, meaning that a least square solution is possible. The major innovation in this method is a closed‐form solution to the least squares problem of estimating the random shifts. The least squares solution, using the pseudoinverse, involves a matrix inversion of an N‐1 x N‐1 square matrix, where N is the number of image frames. For a large number of frames, numerically calculating this inverse can become computationally prohibitive. We have discovered a closed‐form solution to this pseudoinverse solution that does not require the calculation of the inverse matrix. In fact, it does not even require holding the least squares matrix, or even the complete cross‐
correlation vector, in memory. Instead, the exact least squares solution can be incrementally determined as each cross‐correlation is measured. This method will be illustrated with images of an unresolved object for which the new re‐centering method has eliminated almost all of the random shifts in the image sequence. IMAGING Page 20 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Pushing the Envelope: HI‐CLASS Range and Range‐Rate Dr. Paul Konkola1, Charles Crandall1, Robert Lercari1, Moe Tun2, Laura Ulibarri3, Jill Watson3 Textron Systems, 2Advanced Technology Corp., 3Air Force Research Laboratory 1
The HI‐CLASS (HIgh Performance CO2 LAdar Surveillance Sensor) operating in conjunction with the AEOS 3.6 meter aperture telescope atop Mt. Haleakala has demonstrated its ability to produce simultaneous precision range (4m in narrow band; 10 cm in wide band), range rate (< 0.25 m/s) and angular position measurements (FWHM beam width of 4 micro‐radians) of both uncooperative ( > 0.1 ‐ 0.2 m diameter) in LEO trajectories and cooperative (retro) satellites. We describe key improvements to the system that help extend the system’s range accuracy toward its precision. The limiting range‐rate error source is also addressed. The system time base has been upgraded. The method and results for calibrating the time base and measuring timing errors over the full time of flight are presented. The upgraded timebase error has been demonstrated to be better than a part per billion when referenced against a second calibrated clock. HI‐CLASS is a heterodyne system and requires filter calibrations to compensate for the group delay inherent in the electronic channels of the out‐going pulse monitor (OPM) and the received signals. These signals have a varying frequency on a pulse‐to‐pulse basis that is largely dependent on the local oscillator‐to‐seed locking stability and the Doppler shift from the target that is un‐cancelled electronically. The method and procedure for calibrating the group delay for both the OPM and the receiver channels is presented. The range‐rate precision and accuracy has been assessed to be limited by the stability of the local oscillator during the time of flight. This assessment is supported by cm/s level noise floor measurements at short range. Also the stability of the local oscillator when referenced against a Freed ultrastable laser is consistent with the velocity noise floor measured against space objects when considering the time of flight. Data is presented for velocity measurements that are corrected using the signal from the ultrastable laser and the local oscillator beat. HI‐CLASS metrics are compared to the truth trajectories derived from the International Laser Ranging Service data. This cm‐level accurate assessment method is used to demonstrate the improvements. Fiber Laser Component Testing for Space Qualification Protocol Development Suzzanne Falvey1, Marisol Buelow1, Burke Nelson1, Yuji Starcher1, Lee Thienel2, Charley Rhodes2, Jackson and Tull2, Major Thomas Drape3, Lt. Caleb Westfall3 1
Northrop Grumman Information Technology, 2Space and Aeronautics Technology Division, 3Air Force Research Laboratory, Air Force Materiel Command A test protocol for the space qualifying of Ytterbium‐doped diode‐pumped fiber laser (DPFL) components was developed under the Bright Light effort, sponsored by AFRL/VSE. A literature search was performed and summarized in an AMOS 2005 conference paper that formed the building blocks for the development of the test protocol. The test protocol was developed from the experience of the Bright Light team, the information in the literature search, and the results of a study of the Telcordia standards. Based on this protocol developed, test procedures and acceptance criteria for a series of vibration, thermal/vacuum, and radiation exposure tests were developed for selected fiber laser components. LASERS Page 21 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Northrop Grumman led the effort in vibration and thermal testing of these components at the Aerospace Engineering Facility on Kirtland Air Force Base, NM. The results of the tests conducted have been evaluated. This paper discusses the vibration and thermal testing that was executed to validate the test protocol. The lessons learned will aid in future assessments and definition of space qualification protocols. Components representative of major items within a Ytterbium‐doped diode‐pumped fiber laser were selected for testing; including fibers, isolators, combiners, fiber Bragg gratings, and laser diodes. Selection of the components was based on guidelines to test multiple models of typical fiber laser components. A goal of the effort was to test two models (i.e. different manufacturers) of each type of article selected, representing different technologies for the same type of device. The test articles did not include subsystems or systems. These components and parts may not be available commercial‐off‐the‐
shelf (COTS), and, in fact, many are custom articles, or newly developed by the manufacturer. The primary goal for this effort is a completed taxonomy that lists all relevant laser components, modules, subsystems, and interfaces, and cites the documentation for space qualification of each of these all the way to the system level. As a result of the current effort, a validated protocol was developed for the space qualification of DPFLs, where validation via selected tests was mostly limited to the component level. It was the mission of this effort to validate selected aspects of the protocol with the limited set of tests proposed. The results of the environmental testing as well as lessons learned for space qualification of DPFL components are presented in this paper. Telescope Spectrophotometric and Absolute Flux Calibration, and National Security Applications, Using a Tunable Laser on a Satellite Justin Albert1, William Burgett2, Jason Rhodes3, 4 Department of Physics, California Institute of Technology, 2Institute for Astronomy, University of Hawaii, 3Jet Propulsion Laboratory, 4Department of Astronomy, California Institute of Technology 1
We propose a tunable laser‐based satellite‐mounted spectrophotometric and absolute flux calibration system, to be utilized by ground‐ and space‐based telescopes. As uncertainties on the photometry, due to imperfect knowledge of both telescope optics and the atmosphere, will in the near future begin to dominate the uncertainties on fundamental cosmological parameters such as ΩΛ (Omega_Lambda) and w in measurements from SNIa, weak gravitational lensing, and baryon oscillations, a method for reducing such uncertainties is needed. We propose to improve spectrophotometric calibration, currently obtained using standard stars, by placing a tunable laser and a wide‐angle light source on a satellite by early next decade (perhaps included in the upgrade to the GPS satellite network) to improve absolute flux calibration to 0.1% and relative spectrophotometric calibration to better than 0.001% across the visible and near‐infrared spectrum. As well as fundamental astrophysical applications, the system proposed here potentially has broad utility for defense and national security applications such as ground target illumination and space communication. For further details please see http://www.arxiv.org/abs/astro‐
ph/0604339. LASERS Page 22 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Wavefront Correction on High Repetition Rate, High Energy Laser System Zhi M. Liao Lawrence Livermore National Laboratory Diode‐pumped solid‐state lasers are one of the potential driver technologies for inertial fusion energy power production. The Mercury Laser at Lawrence Livermore National Laboratory is a diode‐pumped solid‐state laser that will deliver 100 J of energy at 1047 nm with a repetition rate up to 10 Hz and is a scalable prototype of a fusion energy laser driver. As the Mercury laser undergoes proof‐of‐principal design and activation, high‐repetition wavefront correction is one of the advanced components that will be tested within its unique four‐pass architecture. High average power operation of the Mercury Laser induces dynamic aberrations to the laser beam wavefront. Analysis of recent data indicates that up to 4 waves of low order aberration (mainly focus error or power, with spatial resolution < 0.5 cm‐1) could be expected at each pass. The Mercury laser system uses a custom‐designed high‐repetition‐rate adaptive optics system that consists of a 100‐mm diameter bimorph deformable mirror (DM) and a four‐way shearing interferometric wavefront sensor capable of running at 10 Hz with very high resolution (100 x 100 sample points). The DM is based on lead zirconate titanate (PZT) technology and is coated with a high‐damage threshold antireflection (AR) coating (> 10 J/cm2). The DM has a 5 x 8 actuator configuration with an additional large actuator for power correction (up to 20 waves) for a total of 41 actuators. The DM has a flatness of 0.9 waves peak to valley (PV), which with full correction reduces to 0.17 waves PV and 0.03 waves root mean square (RMS). Placing the deformable mirror (DM) at an image relay point on the laser system between passes allows the DM to be twice as effective in correcting the wavefront. The AO system was able to successfully close the loop on the laser; reducing the wavefront error from 7.2 waves PV and 1.9 waves RMS to 0.83 waves PV and 0.15 waves RMS. Analysis of the residual wavefront shows that all but 0.1 waves PV and 0.04 waves RMS of the residual wavefront errors are high spatial frequency distortions arising from crystal imperfections (which is above and beyond what the current DM can correct). Compact Fiber Laser for 589 nm Laser Guide Star Generation D. M. Pennington, J. Dawson, A. Drobshoff, S. Mitchell, A. Brown Lawrence Livermore National Laboratory Abstract unavailable. Sodium Guidestar Radiometry Results from the SOR’s 50W Fasor Jack Drummond1, John Telle1, Craig Denman1, Paul Hillman1, Gerald Moore1, Steven Novotny1, Robert Fugate1, Mark Eichoff2 Starfire Optical Range, AFRL/DES, 2Boeing, LTS 1
Having upgraded the 20W, 589nm fasor (frequency‐addition source of optical radiation) reported at the last AMOS conference to 50W, we have since produced a sodium laser guidestar (LGS) with a V1 magnitude of 5.1 for 30W of fasor power in November 2005, when the annual peak in mesospheric LASERS Page 23 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS sodium density occurs. This corresponds to a return flux at the top of the telescope of 7000 photons/s/cm2 through one airmass. Late in May 2006, however, a return of only 1340 ph/s/cm2 (V1=6.7) for 30 W of fasor power was obtained at the annual minimum in sodium column density. Earlier in the month, with 49 W of fasor power, the LGS was only as bright as V1=6.3 because of the minimum in column density. By measuring the LGS return flux in circular polarization from various altitudes and azimuths, we have detected the presence of the Earth’s magnetic field, for the first time ever, as an enhancement in flux from the direction where the field lines are pointing at the SOR. We then give a formulation to predict the brightness of the LGS as a function of direction and time of year. The fasor, itself, is continuously tunable to as fine as 60 femtometers (6x10‐6 Angstroms) across the entire sodium D2 line (FWHM ~3 GHz) and is capable of pumping either the D2a or D2b feature with linear or circular polarization. Spectral scans will be shown. While saturation is now being seen for linear polarization, we have seen little, if any, saturation for circular polarization at higher laser powers, and circular produces more than twice the return of linear because of optical pumping. We have succeeded in closing the adaptive optics loop on this very bright LGS, resolving a 0.14 arcsec binary star in June 2006. Adaptive Beam Director for a Tiled Fiber Array: Concept Development, Numerical Modeling and Experimental Design Mikhail A. Vorontsov1, 2, Jim F. Riker2, Ernst Polnau3, Svetlana L. Lachinova3, V. S. Rao Gudimetla2 Intelligent Optics Laboratory, Computational and Information Sciences Directorate, U.S. Army Research Laboratory, 2AFRL/DESM, Air Force Research Laboratory, 3Intelligent Optics Laboratory, Institute for Systems Research, University of Maryland 1
We present the concept development of a novel atmospheric compensation system based on adaptive tiled fiber array (ATFA) operating with target‐in‐the‐loop (TIL) scenarios for directed energy applications. The ATFA system is integrated with adaptive beam director (ABD) with wavefront control and sensing functions performed directly on a beam director telescope primary mirror. The ATFA beam control aims to compensation of atmospheric turbulence‐induced dynamic phase aberrations and a corresponding extended target brightness increase. The system is specifically designed for tiled fiber system architectures operating in strong intensity scintillation and speckle‐modulation conditions typical for extended targets and includes both local (on‐tile) wavefront distortion compensation and phase locking of sub‐systems. The compensation algorithms are based on adaptive optimization of performance metrics. Local wavefront distortion compensation is performed using on‐tile stochastic parallel gradient descent (SPGD) optimization of local speckle metrics directly measured on each fiber‐
tile. Phase locking is performed using SPGD optimization of a composed metric, that is, the metric combined from local metrics. An experimental setup is developed to evaluate the feasibility of controlling beam quality by using speckle metrics based on the temporal analysis of the speckle pattern of light which is backscattered from an extended target and recorded by a single photo detector. The experimental setup is used to investigate beam quality improvement, adaptive process convergence speed, and the influence of target shape. LASERS Page 24 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Recent Research at the JPL Optical Communications Telescope Laboratory K. E. Wilson, M. Wright, M. Troy, J. Roberts, W. T. Roberts Jet Propulsion Laboratory, California Institute of Technology The Optical Communications Telescope Laboratory is a state‐of‐the‐art facility located at 2.2‐km altitude on Table Mountain Wrightwood, CA. Designed for nighttime and daytime operation, the 1‐m OCTL telescope tracks targets as close as 10‐degrees to the sun, and satellites as low as 250‐km. Maximum slew rates are 10 deg/sec elevation and 20 deg/sec azimuth. Research projects at the OCTL include passive and active satellite tracking of retro‐reflecting satellites, technology development for safe laser beam transmission into deep space, line‐of‐sight cloud detection, and adaptive optics correction of atmosphere‐
induced optical wavefront aberrations. OCTL tracks LEO, MEO and HEO satellites and is authorized by various satellite owners to transmit 532‐nm and 1064‐nm laser beams to several of their retro‐reflector bearing satellites; work that is currently under development. Our strategies for safe laser transmission through navigable airspace have been coordinated with the FAA, and use the JPL three‐tiered laser beam propagation system. Laser transmission is also coordinated with the Laser Clearinghouse that provides daily predictive avoidance windows for transmission to target satellites. Backscatter from clouds along the uplink line‐of‐sight is measured by a 0.15 degree field‐of‐view 20‐cm acquisition telescope bore sighted with the 1‐m telescope transmitter. Designed for daytime wavefront correction, the ninety‐seven actuator deformable mirror across the 1‐m makes the OCTL adaptive optics system has one of the highest actuator densities in operation. This paper describes early results from these research areas. Field Demonstration of an Active Laser Tracking System (ALTS) Vladimir Markov1, Anatoliy Khiznyak1, Dirk Woll1, Shiang Liu2 1
MetroLaser Inc., 2The Aerospace Corporation Comprehensive space surveillance demands a more accurate technique in tracking multi‐dimensional state vector (3D coordinate, velocity, vibration, etc.) of the space objects. RF radiometric techniques typically can not provide the needed accuracy, while passive optical (and laser) tracking systems can provide distance to the object and its angular position, but not a direct reading of velocity, the parameter of primary importance for space object tracking and characterization. Addressing this problem with active optical tracking techniques is challenging because of the great distances involved, the high velocity of the satellites, and the optical aberrations induced by the atmosphere. We have proposed a phase conjugation based laser tracking concept, and accomplished the first version of design and engineering of a prototype for an Active Laser Tracking System (ALTS). In its current state the ALTS is capable to demonstrate the very basics operational principles of the proposed active tracking technique. We then performed a number of experiments to prove operational capabilities of this prototype both at MetroLaser’s lab environment and at Edwards AFB Test Range. In its current architecture the ALTS is comprised of two laser cavities, Master and Slave that are coupled through a Phase Conjugate Mirror (PCM) formed in a non‐linear medium (NLM) set at Master laser cavity. By pumping NLM and forming PCM, Master laser establishes the cavities coupling mode and injects the photons in the slave cavity. It is essential that the specific features of the PCM not only serve to couple ALTS cavities, but also serves to compensate optical aberrations of the ALTS (gain media and LASERS Page 25 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS optical elements of the laser resonator). Due to its ability to compensate optical aberrations, phase conjugate resonators are capable of sustaining oscillation with a remote target as an output coupler. The entire system comprises of several modules, including a laser, emitting/receiving telescope, gimbal‐
mirror module for laser beam steering and detectors, all set on a single platform. In the initial ALTS design, the laser module is conceptualized in coupled‐cavitiesarchitecturewith a synchronously pumped gain media, a four‐wave mixing PCM. The four‐wave mixing arrangement uses optical phase conjugation to compensate for spatial inhomogeneities of the atmosphere. A significant innovation in the proposed approach is in its perspective capabilities to detect and measure the critical parameters in the returned signal that should allow to directly measure spatial/angular position and velocity of the target. This report will cover the system analysis, the ALTS design, test plan and exit criteria, functional and operational tests, and test results at Edwards AFB Range field. LASERS Page 26 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Pan‐STARRS – A New Generation Optical Survey Telescope System N. Kaiser and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy The University of Hawaii Institute for Astronomy is developing a large optical synoptic survey telescope system: the Panoramic Survey Telescope and Rapid Response System. When completed, Pan‐STARRS will consist of an array of four 1.8m optical subsystems with a very large field of view (7 square degrees). Each optical system will be equipped with a 1.4 billion pixel CCD camera possessing low noise and rapid readout features. The collected image data will be reduced in near real time to produce both cumulative static sky and difference images from which stationary transients or variables and moving objects can be detected. Pan‐STARRS will be capable of surveying up to ≈6000 square degrees per night to a detection limit of approximately 24th magnitude. A major goal of the project is to survey for potentially hazardous objects (PHOs) with Pan‐STARRS capable of detecting and establishing orbits for most objects down to 300m size, a 3x improvement over the current best asteroid search programs. In addition, Pan‐STARRS data will be used to address a wide range of astronomical questions in the Solar System, the Galaxy, and the Cosmos at large. This talk is intended to outline the Pan‐STARRS science goals, the top‐level science requirements, and the various survey modes needed to support these goals. A detailed comparison is made between the performance metric for Pan‐STARRS and the future LSST design. We show simulated projected completeness for detection of PHOs of various impact energies, and indicate the capability of Pan‐
STARSR to conduct dark energy science in anticipation of future programs such as LSST or JEDI. The Pan‐STARRS Telescope #1 – PS1 and the PS1 Science Mission K. C. Chambers and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy The Pan‐STARRS Telescope No. 1 (PS1) is a prototype telescope for a large optical synoptic survey telescope system; the Panoramic Survey Telescope and Rapid Response System. PS1 is a 1.8m wide field telescope with a 7 square degree field of view and an unprecedented 1.4 Gigapixel Camera located on the summit of Haleakala, Maui, Hawaii. PS1 will be able to scan the entire visible sky to approximately 23rd magnitude in less than a week, and this unique combination of sensitivity and cadence will open up many new possibilities in time domain astronomy and address a wide range of astrophysical problems in the Solar System, the Galaxy, and the Universe. A description of the PS1 capabilities, science drivers, and the PS1 Science Reference Mission will be presented. The main goals of the Reference Mission are a 5 bandpass (grizy) 3π steradian photometric and astrometric survey, a 5 bandpass ~50 square degree medium deep survey, and a single wide band (w=g+r+i) ecliptic plane survey primarily for Solar System studies and Near Earth Asteroids. PAN‐STARRS Page 27 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Space Situational Awareness Applications of the PS1 AP Catalog Dave Monet and the Pan‐STARRS Project Team US Naval Observatory Flagstaff Station, University of Hawaii, Institute for Astronomy New requirements for accuracy, sensitivity, and timeliness in Space Situational Awareness (SSA) flow down into requirements for star catalogs that provide in‐frame metrics. Star catalogs are being used to provide the (astro‐)metric calibration of the focal plane sensor(s) as well as for the photometric calibration. In many cases, the SSA sensor does not have traditional astronomical filters, so the transformation between the internal and external color systems becomes an issue. The Pan‐STARRS prototype telescope, PS1, will generate an AP catalog with 10 milliarcsecond astrometric accuracy and (at least) 2% photometric accuracy in 5 different colors that should be useful for many SSA applications. The Pan‐STARRS Moving Object Processing System Robert Jedicke and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy A major Pan‐STARRS goal is to survey potentially hazardous objects, where Pan‐STARRS expects to achieve ~90% completion for objects >300m in diameter. Solar system surveying will take place in a search pattern, cadence and broadband filter optimized for detection of asteroids. In developing its software, the moving object processing system (MOPS) has created a synthetic solar system model (SSM) with over 10 million objects whose distributions of orbital characteristics match those expected for objects that Pan‐
STARRS would observe. The MOPS employs novel techniques in handling the computationally difficult problem of linking large numbers of unknown asteroids in a field of detections and verifies its correct operation by simulating the survey and subsequent discovery of synthetically generated objects. We will describe the creation and verification of the Pan‐STARRS MOPS SSM, demonstrate synthetic detections and observations by MOPS, describe MOPS asteroid linking techniques, describe the accuracy and throughput of the entire MOPS system, and provide predictions regarding the numbers and kinds of objects, including as yet undiscovered ʺextreme objectsʺ, that MOPS expects to find over its 10‐year lifetime. The Design of the Pan‐STARRS Telescope #1 J. Morgan, W. Siegmund, C. Hude and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy The Pan‐STARRS project at the University of Hawaii Institute for Astronomy has recently begun commissioning a 1.8m Cassegrain telescope with a 7 square degree field of view at the Haleakala summit on Maui. This telescope is known as PS1, and is a prototype for the four optical subsystems comprising the final Pan‐STARRS (PS4). For this wide field application, the optical layout utilizes a very large secondary mirror, 3 refractive corrector elements, and mirror supports that allow 5 degrees of freedom for both primary and secondary mirrors. There is an additional design driver due to the 650 kg load imposed by the camera, shutter, filter mechanism, and their support structures. This talk presents the PAN‐STARRS Page 28 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS design of the PS1 optics and telescope structure highlighting the challenges in meeting the image quality and survey operations requirements, and we present the adopted design solution that incorporates an EOST 2.4‐meter telescope fork and gimbal. In addition, the design of the PS1 enclosure is shown. Finally, data from the telescope commissioning is discussed. Pan‐STARRS PS1 Observatory, Telescope and Instrumentation Control E. A. Pier, K. C. Chambers and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy An ultimate goal for the final Pan‐STARRS array (PS4) is fully robotic facility operations. To facilitate that development, PS1 is a remotely operable observatory that includes many features of the future robotic Pan‐STARRS. Both remote and robotic operational concepts require sufficient knowledge of environmental conditions to support survey scheduling, and this requires an auxiliary instrumentation suite to measure meteorological and atmospheric conditions in addition to the control systems for the observatory and telescope. For the Pan‐STARRS PS1 prototype, the monitoring, control, and summit subsystem coordination are handled by the HW/SW within the Observatory, Telescope, and Instrumentation Subsystem (OTIS). In this talk, we present the functional capabilities of OTIS, and the HW and SW architectures designed to meet the subsystem operational requirements. OTIS performance through early commissioning is described as well as the future plans to incorporate the Pan‐STARRS scheduler into system operations.
Filter Mounting and Mechanism Design for the Pan‐STARRS PS1 Prototype Telescope System A. J. Ryan, J. Morgan, W. Siegmund, C. Hude and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy The Pan‐STARRS PS1 telescope is a 1.8m Cassegrain telescope with a 7 square degree field of view and a 1.4 billion pixel CCD camera. The required clear aperture at the filters is 496mm in diameter, and therefore the filters needed are quite large. The Pan‐STARRS filter complement consists of six octagonal shaped filters that have a distance between the flats of 538mm and a thickness of 10mm. The automated mechanism that will move the filters needs to fit into a small area. A filter wheel would be prohibitively large, so the mechanism will consist of three layers with two athermally mounted filters that slide on each layer. Each layer will be identical to the other two to provide interchangeability and commonality in manufacturing. The layers will be stacked and held together with top and bottom cover plates to form a rigid structure. The shutter will be mounted to the bottom of the mechanism and they will be installed as one unit. A separate structure will be utilized to clamp the mechanism to the telescope cassegrain core registration points. This installation system will allow the mechanism to be isolated from other structural loads and be easily removed without affecting the camera. This talk will present the detailed design of the mechanism an its performance to date. PAN‐STARRS Page 29 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS The Pan‐STARRS Imaging Sky Probe B. R. Granett, K. C. Chambers, E. A. Magnier and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy Photometric performance is limited by systematic errors introduced by uncertainty in the transparency of the Earthʹs atmosphere. Precision photometry required for programs including the characterization of supernovae and photometric redshifts can especially benefit from independent knowledge of the atmospheric transmission. In particular, multicolor near‐simultaneous observations are able to constrain the impact of aerosol, dust, and water vapor on the atmospheric transparency. To measure the atmospheric transmission function in real time, the Pan‐STARRS PS1 prototype system will utilize auxiliary instruments: imaging, spectroscopic, and potentially u‐band sky probes. These instruments will act synchronously with the primary survey camera to provide calibration data for the Image Processing Pipeline (IPP), and will also generate significant all‐sky science data. For the Imaging Sky Probe (ISP), the broad‐band transparency of the atmosphere will be measured in 5 survey bands matched to the Pan‐STARRS grizy filter set. Atmospheric absorption and transmission models will then be generated to produce a best‐fit characterization of the atmosphere at the time of observation. Armed with measurements of the atmospheric transmission from the sky probe instruments, the Pan‐STARRS IPP can precisely solve for the intrinsic source photometry. Such a system is unprecedented, and the Pan‐
STARRS PS1 system will act as the test bed for future development. The intent of this talk is to describe in detail the design and testing of the ISP which is the first Pan‐STARRS sky probe, and we will present ISP images collected during the early commissioning of PS1. The Pan‐STARRS u‐Band Imaging Probe (UIP) K.W. Hodapp, K.C. Chambers and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy This paper describes the scientific rationale, the design, and the expected data products of the u‐band Imaging Probe (UIP) for Pan‐STARRS. The Pan‐STARRS photometric survey itself will be conducted in the g, r, i, z, and y bands and cover the 3/4 of the sky accessible from Haleakala. In parallel to the survey conducted with the PS1 1.8m telescope, an Imaging Sky Probe (ISP, Granett et. al., these proceedings) will monitor the sky conditions, variations in transparency across the 3° field of view, provide a characterization of the astronomical diffuse sky brightness, and extend the dynamic range of PS1 stellar photometry to the brightest stars. The u‐band Imaging Probe is an additional small wide‐field camera to extend this bright star photometric survey to the shortest wavelengths accessible from ground‐based observatories. It will thereby establish a well characterized photometric system at these wavelengths with a dense sample of stars covering 3/4 of the entire sky, including the galactic plane. The UIP will continuously make dedicated u‐band measurements, and the large number of these independent measurements together with substantial overlapping fields of view and repeated visits to standard star fields as part of the PS1 mission, has the potential of substantially improving u‐band calibration and photometry across the sky over all previous u‐band imaging and catalog surveys. For specific future observations with larger telescopes, this system of stars will serve as secondary calibration PAN‐STARRS Page 30 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS stars to tie these deeper observations into the photometric system established in this way. The UIP is currently in the early design stages. The UIP will be operated as an extension of the PS1 Imaging Sky Probe (ISP), and the data will be processed through the same data reduction pipeline and be made available as part of the photometric survey. The Pan‐STARRS Gigapixel Camera J. L. Tonry, P. Onaka, G. Luppino, S. Isani and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy The Pan‐STARRS project will undertake repeated surveys of the sky to find “Killer Asteroids”, everything else which moves or blinks, and to build an unprecedented deep and accurate “static sky”. The key enabling technology is a new generation of large format cameras that offer an order of magnitude improvement in size, speed, and cost compared to existing instruments. In this talk, we provide an overview of the camera research and development effort being undertaken by the Institute for Astronomy Camera Group in partnership with MIT Lincoln Laboratories. The main components of the camera subsystem will be identified and briefly described as an introduction to the more specialized talks presented elsewhere at this conference. We will focus on the development process followed at the IfA utilizing the orthogonal transfer CCD in building cameras of various sizes from a single OTA “μcam”, to a 16‐OTA “Test Camera”, to the final 64‐OTA 1.4 billion pixel camera (Gigapixel Camera #1 or GPC1) to be used for PS1 survey operations. We also show the design of a deployable Shack‐Hartmann device residing in the camera and other auxiliary instrumentation used to support camera operations. The Pan‐STARRS PS1 Calibration System J. L. Tonry, C. W. Stubbs, J. Masiero and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy The Pan‐STARRS PS1 prototype system has a goal of achieving 1% photometry, and to reach this goal, several challenging system and subsystem requirements must be met. A calibration system for the PS1 camera is a critical component in the current system design that should allow PS1 to meet the 1% photometry goal. In this talk, we briefly review the main challenges in breaking through the 1% precision barrier, we identify and discuss approximations and limitations inherent in the present methodology, and we propose an alternative scheme for the relative calibration of astronomical instruments. The proposed conceptual scheme exploits the availability of tunable lasers to map out the relative wavelength response of an imaging system using a flatfield screen and a calibrated reference photodiode. We show how the conceptual scheme is being implemented for the calibration system to be used with the Pan‐STARRS PS1 prototype telescope at the Haleakala summit. PAN‐STARRS Page 31 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Pan‐STARRS PS1 GRASP Controller P. Onaka, J. L. Tonry, S. Isani, A. Lee, R. Uyeshiro, C. Rae, L. Robertson, G. Ching and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy The requirements for rapid readout and low noise combined with the unprecedented number of pixels in the Pan‐STARRS camera (~1.4 Gigapixels) poses a challenge for the design of the readout and signal chain electronics. This talk presents the design of the hardware and software for the Pan‐STARRS Gigapixel Readout Array and Signal Processing controller (GRASP). Compared to other controllers, the current design also yields a significant reduction in physical size and number of required PCBs with a corresponding reduction in power consumption. Over the past two years, Pan‐STARRS controller development has been rapid with the current GRASP performance meeting requirements. Finally, we will also briefly discuss potential design directions for future controllers. The Pan‐STARRS PS1 Image Processing Pipeline E.A. Magnier and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy The Pan‐STARRS PS1 Image Processing Pipeline (IPP) performs the image processing and data analysis tasks needed to enable the scientific use of the images obtained by the Pan‐STARRS PS1 prototype telescope. The primary goals of the IPP are to process the science images from the Pan‐STARRS telescopes and make the results available to other systems within Pan‐STARRS. It also is responsible for combining all of the science images in a given filter into a single representation of the non‐variable component of the night sky defined as the “Static Sky”. To achieve these goals, the IPP also performs other analysis functions to generate the calibrations needed in the science image processing, and to occasionally use the derived data to generate improved astrometric and photometric reference catalogs. It also provides the infrastructure needed to store the incoming data and the resulting data products. The IPP inherits lessons learned, and in some cases code and prototype code, from several other astronomy image analysis systems, including Imcat (Kaiser), the Sloan Digital Sky Survey (REF), the Elixir system (Magnier & Cuillandre), and Vista (Tonry). Imcat and Vista have a large number of robust image processing functions. SDSS has demonstrated a working analysis pipeline and large‐scale databasesystem for a dedicated project. The Elixir system has demonstrated an automatic image processing system and an object database system for operational usage. This talk will present an overview of the IPP architecture, functional flow, code development structure, and selected analysis algorithms. Also discussed is the HW highly parallel HW configuration necessary to support PS1 operational requirements. Finally, results are presented of the processing of images collected during PS1 early commissioning tasks utilizing the Pan‐STARRS Test Camera #3. PAN‐STARRS Page 32 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Pan‐STARRS PS1 Published Science Products Subsystem J. Heasley, W. L. Smith, R. E. Eek, J. A. Rosen and the Pan‐STARRS Project Team University of Hawaii, Institute for Astronomy This paper describes the requirements and design of the Pan‐STARRS PS1 Published Science Products Subsystem (PSPS) that constitutes the primary distribution tool for the very large amount of science data products produced by the Pan‐STARRS PS1 prototype telescope. The data management challenges are identified in terms of stressing characteristics: dynamic, fast, spatial, and large; these are countered by mitigating characteristics: simple and lenient. This combination of characteristics is not only distinctly more demanding than traditional survey astronomy data managers, but lies at the boundaries of current commercially available data management technology. The requirements imposed on the PSPS result in devising a design strategy at the boundaries of currently available data management technology. In particular, we describe the capabilities and characteristics of the four main PS1 PSPS components: the Web‐Based Interface (WBI), the Data Retrieval Layer (DRL), the Object Data Manager (ODM), and the Solar System Data Manager (SSDM). Potential architectural strategies are examined in the context of the stressing and mitigating characteristics with the conclusion that the ODM should follow an architectural concept that emphasizes the pooling of application, processing, and storage resources. The PS1 PSPS is specifically designed to support the PS1 science mission (see K.C. Chambers et al., these proceedings) while at the same time providing substantial design direction for a future PSPS component of the final PS4 Pan‐STARRS. Finally, the limitations and possible scalability of the PS1 design relative to PS4 are discussed. PAN‐STARRS Page 33 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS The Black Fringe Wavefront Sensor: Real Time Adaptive Optics with Minimum Computation Richard J. Tansey, Henry Chan, Avinash Hokam Advanced Technology Center, Lockheed Martin A new adaptive optics device called a black fringe wavefront sensor ( bfwfs) has been developed over the last year at Lockheed Martin’s Advanced Technology Center.1 Current white light interferometry techniques used for microscopy surface height scans, as used in Linnick and Mirau Interferometers, are combined with am demodulation algorithms from the rf communication industry to produce a wavefront sensor capable of real time adaptive optics correction using white light or broadband multiline incoherent lasers or LED’s. In this presentation the bfwfs will be described, and results of recent tests using a 16 channel device will be discussed. In addition, a planned 64 ch version being fabricated for a deformable mirror and Mems application will be described. The 16 ch device is used to obtain measurements of open loop influence functions, poke tests, and closed loop Bode plots using a Mems mirror. The black fringe wavefront sensing device uses a fully parallel architecture and allows analog control of most wavefront correction devices used today including deformable mirrors, Mems, Liquid Crystal spatial light modulators, and Bimorphs. This control is obtained without the need for a complicated algorithm or computation, other then a minimum number of multiply and divide circuits as needed for peek seeking detection. The bfwfs device can be used for adaptive optics at long ranges, on weight or volume limited platforms, because it allows high power incoherent lasers, or other sources, to be combined with a massively parallel architecture and inherently analog design. Results are reported in which recently developed superluminescent laser diodes (SLD’s) and high brightness white LED’s are tested for use with the black fringe wavefront sensor for long range atmospheric correction. Finally, a potential application of the bfwfs is discussed in which the recently discovered phenomena of white light filaments generated in the atmosphere by a fsec laser is proposed for guide star correction of images or directed energy propagation. 1. R.J.Tansey, “Black Fringe Wavefront Sensor”, patent pending, 10/26/05, Lockheed Martin/Advanced Technology Center, 3251 Hanover St., Palo Alto, Ca., 94304 Use of a Radial Shear Interferometer as a Self Reference Interferometer in Adaptive Optics Richard J. Tansey, Adam Phenis, Ker‐Li Shu Advanced Technology Center, Lockheed Martin A radial shear interferometer (rsi) is produced by the interference of two different sized images of the test wavefront. When the center of curvature of the wavefronts are at the same location, they produce a shear in the radial direction. The rsi has a unique attribute which distinguishes it from other wavefront shear interferometers. For sufficiently large shears S, where S = R1/R2, R being the radius of inner or outer beam, the interferometric fringe pattern is almost identical to a Michelson amplitude splitting interferometer. The usual conversion of measured phase tilt to wavefront phase, as required in other shear interferometers, is avoided. The resultant wavefront reconstruction is eliminated, and the radial shear interferogram can be treated as a direct phase measurement. ADAPTIVE OPTICS Page 34 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Developed for optical testing in prelaser days, the radial shear interferometer was a prime candidate for our use with the black fringe wavefront sensor (bfwfs) described in a companion presentation at this conference.1 We also considered a point diffraction interferometer (pdi) as a self reference interferometer, which led to a testing program to analyze the attributes of each of these optical designs for their later incorporation into an adaptive optics control system with the bfwfs.. The rsi has several advantages over the pdi, including more efficient use of the input light from the test wavefront and insensitivity to vibration and environmental disturbances, due to the common path nature of the coincident wavefronts. However, the radial shear interferometer is hampered by at least two issues in its implementation: the measured wavefront is only an approximation to the true input wavefront (based on the shear ratio), and it cannot be used with a centrally obscured telescope because of the radial shear. The remainder of the presentation will summarize an experimental investigation in which various wavefront aberrations are introduced at the input of a radial shear interferometer and the resultant wavefront error map obtained. This phase map will be compared with that obtained when similar aberrations are input to a point diffraction interferometer. There is a common theme to the recent successful applications of curvature sensing, image sharpness algorithms, and stochastic optimization techniques in adaptive optics. All aberrations do not need to be corrected to obtain either better images or corrected outgoing wavefronts, and averaging techniques can be a viable alternative for adaptive optics correction in severely degraded atmospherically generated or high flow conditions. The use of a radial shear interferometer, combined with a black fringe wavefront sensor is finally described as an alternative method to correct for many of these aberrations, and, to the best of our knowledge, represents the first use of an rsi for atmospheric correction. 1. R.J.Tansey, H. Chan, A. Hokam, ”The Black fringe Wavefront Sensor”, Amos Technical Conference, Sept 10‐14, 2006 Laboratory Demonstration of a Correlation‐Based Adaptive‐Optical System for Wavefront Sensing of Extended Objects Troy A. Rhoadarmer Optics Division, AFRL/DESA, Directed Energy Directorate, U.S. Air Force Research Laboratory Over the last few decades, adaptive‐optical (AO) techniques have been developed to mitigate the deleterious effects of atmospheric turbulence on imaging systems. Traditionally, AO systems have relied on a point source beacon, either a natural star or a generated laser guide star, to provide a reference for the wavefront sensor (WFS). However, for passive, remote imaging applications, such a reference source is not generally available and the extended nature of the object can severely degrade the performance of conventional Hartmann WFSs using quad‐cell or other centroid estimation approaches. Correlation wavefront sensing has been proposed as a means of improving AO performance in these applications. Correlation methods are more accurate and robust and less sensitive to noise than centrioding algorithms. Over the last year, researchers at the Starfire Optical Range (SOR), Optics Division, Air Force Research Laboratory, have been developing a correlation WFS for remote imaging of extended objects. The design of a prototype sensor is described and results from a laboratory demonstration performed in the SOR’s ASALT Laboratory are presented. ADAPTIVE OPTICS Page 35 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Packet Switching Networks for Adaptive Optics Systems Robert J. Eager Boeing, LTS High Performance and Extremely Large Adaptive Optics systems place great demands on the data distribution and electronic control sub‐systems. These servo‐loop sub‐systems acquire, process, and drive electro‐optical/mechanical devices with large degrees of freedom. Two of the key parameters which affect AO loop performance are latency and jitter. To minimize these parameters, data must be efficiently acquired from sensors, processed into servo commands and then distributed to actuators. In addition to these critical path activities, there is also a requirement to “tap” into many points in the processing pipeline to monitor, characterize and perform high‐level corrections. One answer to this communications dilemma is the use of a low‐latency packet switched network. This paper illustrates the actual performance and flexibility of such a network by describing the high‐performance system used at the Starfire Optical Range. The paper will then demonstrate the adaptability of this network architecture to accommodate the more complex communication requirements of extremely large AO systems. Modular Adaptive Optics Testbed for the NPOI Jonathan R. Andrews1, Ty Martinez1, Christopher C. Wilcox1, Sergio R. Restaino1, Scott W. Teare2, Don M. Payne3 Naval Research Laboratory, Remote Sensing Division, 2New Mexico Institute of Mining and Technology, 3Narrascape 1
The Naval Prototype Optical Interferometer (NPOI) is a long‐baseline, multi‐station interferometer whose collection apertures can be relocated to provide flexible baseline lengths. While NPOI has the longest baseline at optical wavelengths in the world, the sensitivity of the interferometer is limited by the size of the individual collection apertures which are currently 0.5 meters in diameter. NPOI is currently upgrading its collection apertures to 1.4 meter diameter light weight telescopes to increase the sensitivity. At its location on the Anderson Mesa in Arizona, the chosen diameter of the telescope apertures is much larger than the average r0 of the site. As a result, adaptive optics must be used to correct for the wavefront aberrations. Several adaptive optics system configurations are suitable to provide the required wavefront correction, but it is highly desirable to have the adaptive optics systems as a component of the telescopes. This is being accomplished by designing the telescopes so that the adaptive optics system resides in the base of each telescope allowing a truly reconfigurable array. Thus evaluating and characterizing the performance of the adaptive optics systems is a critical component of identifying the desired adaptive optics system to support the move to larger aperture telescopes. This paper outlines a modular, electro‐optical testbed that has been constructed for characterizing candidate adaptive optics systems for use at NPOI. The testbed makes use of innovative technologies to characterize the spatial and temporal performance of an adaptive optics system. Spatial performance is evaluated using a spatial light modulator liquid crystal device while temporal response is evaluated with a fast steering mirror that is used in series with the liquid crystal device. We report on the capabilities of the testbed and on the initial characterization of a low cost portable adaptive optics system. ADAPTIVE OPTICS Page 36 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Characterization of the Variability of the Strehl Ratio of Adaptive Optics Point Spread Functions Julian C. Christou1, Szymon Gladysz2, Michael Redfern2, L. William Bradford3, Lewis C. Roberts, Jr.3 1 Center for Adaptive Optics, University of California, 2 Department of Experimental Physics, National University of Ireland, 3The Boeing Company We have investigated the high‐speed temporal variability of the performance of the adaptive optics systems at both the Lick Observatory 3m and the AEOS 3.6m telescopes. Measurements of the instantaneous Strehl ratio for the Lick Observatory data measurements were obtained using the fastsub readout mode of the IRCAL camera. This set up permits high speed focal plane images to be obtained with exposure times of 22ms at a frame rate of ∼ 20Hz suitable for “freezing” the compensation under typical K‐band (2‐2.45μm) observing conditions. Data from the Lick Observatory system has been accumulated over several months with instantaneous Strehl ratios S varying from ∼ 20%‐70% in natural guide star mode. Data from AEOS is collected by a burst mode capture of 2000 frames of closed‐loop wavefront sensor slope data, typically collected at 200Hz (actually exposure time however is much less). The slope data is the residual error after correction by the DM, and this can be used to form an estimate of the Strehl ratio. These data show that the Strehl ratios can vary considerably over different times scales from seconds to tens of minutes. Under relatively stable conditions, the variability in the instantaneous Strehl ratio ranges for standard deviations of 0.04–0.08 for mean Strehl ratios of 40%—60%. We consistently measure non‐
Gaussian distributions for S which imply a Gaussian distribution for the instantaneous estimate re of the Fried parameter r0. Although taken at very different time scales and very different technique, the distributions of AEOS Strehl ratios bear a strong resemblance to the distributions of Lick Strehl ratios. This work has been supported by the National Science Foundation Science and Technology Center for Adaptive Optics, managed by the University of California at Santa Cruz under cooperative agreement No. AST – 9876783 as well as COSMOGRID (Grid‐enabled Computational Physics of Natural Phenomena) and the U.S. Air Force Research Laboratory’s Directed Energy Directorate under contract (FA9451‐05‐C‐0257 and F29601‐00‐D‐0204). Preliminary Experimental Evidence of Anisotropy of Turbulence at Maui Space Surveillance Site Mikhail S. Belen’kii, Edward Cuellar, Kevin A. Hughes, Vincent A. Rye Trex Enterprises Corporation We investigated the spatial structure of atmospheric turbulence at Maui Space Surveillance Site (MSSS) using a 3.6 m telescope and a spatial filtering receiver and imaging selected stars simultaneously through four pupil masks representing aperture diameters of 0.1 m, 0.5m, 1.5 m, and 3.6 m. In our optical setup, four star images were recorded simultaneously on one camera frame. Multiple data sets of short‐
exposure star images were collected during six nights at frame rates ranging from 100 Hz to 285 Hz. The camera orientation was determined for each data set by moving the telescope at a given angle in azimuth and elevation. The horizontal and vertical components of the image centroid were calculated. The spatial and temporal statistics of the horizontal and vertical wavefront tilt, as well as parameters of the long‐
exposure star images, were determined as a function of the aperture diameter, azimuth, and zenith angle. In addition, the Fried parameter, the outer scale of turbulence, and the turbulence anisotropy coefficient, ADAPTIVE OPTICS Page 37 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS defined as a ratio of the variance of horizontal wavefront tilt to variance of the vertical tilt, were retrieved from the star imagery data. We found that the atmospheric wavefront tilt is anisotropic. On four nights we observed that the on‐axis horizontal tilt variance exceeded the vertical tilt variance by a factor of 1.3 to 3.5. We believe that this is due to anisotropy of large‐scale turbulence, where the horizontal scale of the turbulent inhomogeneities exceeds their vertical scale. The estimates of the horizontal and vertical turbulence outer scale confirmed this conclusion. In addition, in several data sets, the horizontal image spot diameter in the long‐exposure star image exceeded the vertical image spot diameter. We also found that the anisotropy coefficient of the wavefront tilt increased linearly with the aperture diameter. This is because large‐scale turbulent inhomogeneities are anisotropic, whereas small‐scale inhomogeneities are isotropic. When the telescope diameter increases, the contribution of small‐scale isotropic turbulence to the image centroid reduces, whereas the contribution of large‐scale anisotropic turbulence increases. Also, in the case of isotropic turbulence, we found that the power spectral densities (PSDs) of the wavefront tilt are consistent with theoretical models. In the case of anisotropic turbulence, the PSDs of the horizontal and vertical tilt components exhibit different behavior. The telescope vibration modes were observed at 15 Hz and 20 Hz. The anisotropy of turbulence and wavefront tilt should be considered in design and performance analysis of optical trackers. Control System Performance of a Woofer‐Tweeter Adaptive Optics System Peter J. Hampton, Dr. Colin Bradley, Dr. Pan Agathoklis, Dr. R. Conan University of Victoria In the next generation of large optical telescope (LOT), it will be essential to use adaptive optics (AO) systems to achieve optimal image quality. Furthermore, in order to meet the broad set of user requirements, several new AO configurations are currently being investigated for use on proposed LOTs. One configuration currently under investigation at the University of Victoria is the Woofer‐Tweeter system. The Adaptive Optics Laboratory, at the University of Victoria, has recently completed the development of a test bench for this Woofer‐Tweeter concept. This project is part of the Thirty Meter Telescope (TMT) development program that will see completion within the next decade. The actuator density and maximum actuator stroke requirements of deformable mirrors, necessary for the LOTs, increase significantly due to the enormous collecting area of the LOT, operating site seeing, and scientific requirements. It would be cost prohibitive to try and develop a single deformable mirror that satisfies the actuator density and actuator stroke requirements. Fortunately, the large stroke requirement is for the compensation of low spatial frequency distortion. This allows a system to be designed with two deformable mirrors (DMs): (i) a high stroke, low actuator density DM termed the Woofer, and (ii) a low stroke, high actuator density DM termed the Tweeter. The initial simulations and experimental results have shown that the controller developed in this work can appropriately split the correction between the two deformable mirrors. The Woofer, correcting for the low‐spatial‐low‐temporal frequency disturbances, is an electro‐mechanical device, whereas the Tweeter, correcting for the remaining disturbance, is a MEMS device. This paper focuses on the development and need for the woofer‐tweeter test bench; bench design and operating specifications; the deformable mirror technology employed; closed loop control of the bench system when a hot air turbulence generator is introduced into the optical path; and the experimental results. ADAPTIVE OPTICS Page 38 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Hi‐Contrast Cornographic Imager for Adaptive Optics Dr. Klaus W. Hodapp1, Dr. Ryuji Suzuki1, Shane Jacobson1, Vern Stahlberger1, Hubert Yamada1, Dr. Motohide Tamura2, Dr. Lyu Abe2 1
Institute for Astronomy, University of Hawaii, 2National Astronomical Observatory of Japan The Hi‐Contrast Coronographic Imager for Adaptive Optics (HiCIAO) is a new instrument being designed at the Institute for Astronomy for the Japanese National Observatory Subaru 8.3m telescope on Mauna Kea. The new HiCIAO will supercede the capabilities of the existing CIAO (Coronographic Imager for Adaptive Optics) that is currently in use at the Subaru Telescope. HiCIAO will be used in conjunction with a new, high‐order, curvature‐sensing, bimorph‐mirror adaptive optics system currently under construction. This new adaptive optics system will have 188 actuators and will therefore achieve better Strehl ratios than the current generation of adaptive optics systems. HiCIAO is designed for use at the Nasmyth focus of the Subaru Telescope. HiCIAO consists or a system of ambient temperature coronographic foreoptics and Wollaston beamsplitters and of an infrared camera. HiCIAO can operate as a simple, high spatial resolution camera, as a conventional Lyot coronograph, as a polarimetric simultaneous differential imager, and as a spectral simultaneous differential imager. This paper will describe the design and performance predictions of HiCIAO in this “first light” configuration. However, HiCIAO is designed as an experimental system, as opposed to a facility instrument, and will be modified over the coming years to incorporated more advanced coronographic techniques and upgrades to its adaptive optics capabilities. “Pocket” Deformable Mirror for an Integrated On‐Mirror Adaptive System Leonid Beresnev1, Mikhail Vorontsov1, Peter Wangsness2 U.S. Army Research Laboratory, 2Wangsness Optics 1
Existing HEL beam control architectures are extremely complicated because they require installation and alignment of a large number of optical elements, resulting in substantial increase of the entire HEL system size, weight and cost. There is a strong interest in designing new robust beam control capabilities integrated directly to a beam director system. The discussed technical effort is focused on development and demonstration of a new adaptive beam director (ABD) consisting of a beam forming telescope with wavefront compensation integrated solely on its ultra‐
lightweight primary mirror. This on‐mirror AO system will be controlled using a stochastic parallel gradient descent (SPGD) controller specifically designed for target‐in‐the‐loop (TIL) operation. The key component of the on‐mirror AO system is its primary mirror. This mirror contains an array of pockets machined on its backside, called a pocket‐mirror. A special dielectric layer deposited on the front surface of the pocket‐mirror is highly reflective for the HEL wavelength λHEL, and semi‐transparent for the laser illuminator wavelength λILL. Thus the wave λILL scattered by the target surface enters inside the mirror pockets, while the outgoing HEL beam with wavelength λHEL is totally reflected. The pockets of the ABD pocket‐mirror (see Fig. 1) include opto‐electronic components that can provide local (inside pocket‐
window) wavefront correction and sensing. ADAPTIVE OPTICS Page 39 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Fig. 1. Schematic of the “pocket” DM and integrated wavefront sensing and control sub‐systems (left) and the mirror prototype (right). Wavefront correction at each pocket aperture is performed using electrically sectioned piezo‐ceramic annular rings made from thin (~0.3 mm) bimorph discs glued to the pocket bottoms. Control voltages applied to these electrodes result in mechanical deformation of the pocket‐window front surface thus providing compensation of low‐order aberrations at each pocket‐window. Packaging the pockets with a high fill factor allows high resolution control of the beam director primary mirror shape. Preliminary analysis has shown that surface stroke near 3 microns with bandwidth near 10 kHz can be achieved. The example of the DM mirror surface control inside a single pocket is presented in Fig. 2. Fig.2. Profiles of the single pocket surface at different voltages applied to piezoelectric ceramic pixels. Design, Modeling, Installation of the MWIR AO System James Campbell, Dr. Michael Roggemann, Dr. Todd Groesbeck, Dr. Howard Hyman, Daron Nishimoto Trex Enterprises The Navyʹs AEGIS Ballistic Missile Defense (BMD) program required high resolution imagery in support of their tests with targets launched from the Pacific Missile Range Facility (PMRF) on Kauai. In support of this goal, Trex Enterprises designed, modeled and installed the first mid‐wave infrared (MWIR) adaptive optics (AO) system at the Air Forceʹs AEOS Telescope atop Mt. Haleakala on Maui. This paper details the design choices, modeling results, and the successful installation of the MWIR AO system. ADAPTIVE OPTICS Page 40 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS MEMS Deformable Mirrors for Adaptive Optics in Astronomical Imaging S. A. Cornelissen1, P. A. Bierden1, T. G. Bifano1, 2 1
Boston Micromachines Corporation, 2 Boston University We report on the development of micro‐electromechanical (MEMS) deformable mirrors designed for ground and space‐based astronomical instruments intended for imaging extra‐solar planets. Three different deformable mirror designs, a 1024 element continuous membrane (32x32), a 4096 element continuous membrane (64x64), and a 331 hexagonal segmented tip‐tilt‐piston are being produced for the Planet Imaging Concept Testbed Using a Rocket Experiment (PICTURE) program, the Gemini Planet Imaging Instrument, and the visible nulling coronograph developed at JPL for NASA’s TPF mission, respectively. The design of these polysilicon, surface‐micromachined MEMS deformable mirrors builds on technology that was pioneered at Boston University and has been used extensively to correct for ocular aberrations in retinal imaging systems and for compensation of atmospheric turbulence in free‐
space laser communication. These light‐weight, low power deformable mirrors will have an active aperture of up to 25.2mm consisting of thin silicon membrane mirror supported by an array of 1024 to 4096 electrostatic actuators exhibiting no hysteresis and sub‐nanometer repeatability. The continuous membrane deformable mirrors, coated with a highly reflective metal film, will be capable of up to 4μm of stroke, have a surface finish of <10nm RMS with a fill factor of 99.8%. The segmented device will have a range of motion of 1um of piston and a 600 arc‐seconds of tip/tilt simultaneously and a surface finish of 1nm RMS. The individual mirror elements in this unique device, are designed such that they will maintain their flatness throughout the range of travel. New design features and fabrication processes are combined with a proven device architecture to achieve the desired performance and high reliability. Presented in this paper are device characteristic and performance results of these devices. ADAPTIVE OPTICS Page 41 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Recent Results from the ESA Optical Space Debris Survey T. Schildknecht1, R. Musci1, W. Flury2, J. Kuusela3, J. de Leon4, L. de Fatima Dominguez Palmero4 Astronomical Institute, University of Bern, 2ESA ESOC, 3ASRO, 4Instituto de Astrofisica de Canarias 1
In the framework of its space debris research activities ESA established an optical survey program to study the space debris environment at high altitudes, in particular in the geostationary ring and in the geostationary transfer orbit region. The Astronomical Institute of the University of Bern (AIUB) performs these surveys on behalf of ESA using ESA’s 1‐meter Telescope in Tenerife. Regular observations were started in 1999 and are continued during about 100 nights per year. Results from these surveys revealed a substantial amount of space debris at high altitudes in the size range from 0.1 to 1 meter. Several space debris populations with different dynamical properties were identified in the geostationary ring. During the searches for debris in the geostationary transfer orbit region a new population of objects in unexpected orbits, where no potential progenitors exist, was found. The orbital periods of these objects are clustered around one revolution per day, the eccentricities, however, are scattered between 0 and 0.6. By following‐up some of these objects using the ESA telescope and AIUB’s 1‐meter telescope in Zimmerwald, Switzerland, it was possible to study the properties of this new population. One spectacular finding from monitoring the orbits over time spans of days to months is the fact that these objects must have extreme area‐to‐mass ratios, which are by several orders of magnitudes higher than for ‘normal‐type’ debris. This in turn supports the hypothesis that the new population actually is debris generated in, or near the geostationary ring, which is in orbits with periodically varying eccentricity and inclination due to perturbations by solar radiation pressure. In order to further study the nature of these debris multi‐colour and temporal photometry (light curves) were acquired with the Zimmerwald telescope. The light curves show strong variations over short time intervals including signals typical for specular reflections. Some objects exhibit distinct periodic variations with periods ranging from 10 to several 100 seconds. All this is indicative for objects with complicated shapes and some highly reflective surfaces. Orbit Processing and Analysis of a GEO Class of High Area‐to‐Mass Debris Objects Tom Kelecy1, Ray Deiotte1, John Africano1, Gene Stansbery2, Tim Payne3 1
Boeing LTS/AMOS, 2NASA JSC‐KX, 3Air Force Space Command/A9AC, Colorado Springs A population of recently discovered deep space objects is thought to be debris having origins from sources in the geosynchronous orbit (GEO) belt. Observations have been presented indicating that these objects have a high area‐to‐mass (A/M) ratio (1’s to 10’s of m2/kg), and thus would explain the observed migration of eccentricity (0.1‐0.6) and inclination that distinguishes their orbital characteristics. There is a heightened interest in the international community due to the large number and small size of these objects, as they pose a hazard to active satellites operating in the vicinity of the GEO belt. Observational coverage of these objects has been limited by the orbital phasing and the locations of the tracking sites. Boeing, NASA and the U.S. Air Force Space Command have embarked on a collaborative effort with the Inter‐Agency Space Debris Coordination Committee (IADC) to track selected high A/m of this population to more accurately characterize their orbits and orbit histories. Space Command tracking assets were tasked to provide angles measurements for representative set of 6 high A/m objects, and the data were used to establish a process for doing orbit updates that would accommodate a priori two‐line element sets that will eventually be provided by the IADC. ORBITAL DEBRIS Page 42 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS This paper presents the development and validation of the data processing and orbit update implementation, and preliminary analysis results of the high A/m class of objects. Limitations in the observational geometry, along with the apparent time variations in the nominal A/m values of some of the objects, pose a challenge for the orbit prediction. The ultimate goal is to establish a process that will provide long‐term, relatively accurate orbital histories for these high A/m objects derived from a global set of observation metrics, and to capture photometric measurements when possible that will support characterization of these objects. Comparison of Orbital Parameters for GEO Debris Predicted by LEGEND and Observed by MODEST: Can Sources of Orbital Debris be Identified? E. S. Barker1, M. J. Matney1, J.‐C. Liou2, K. J. Abercromby2, H. M. Rodriguez2, P. Seitzer3 National Aeronautics and Space Administration, Johnson Space Center, 2ESCG, 3University of Michigan, Dept. of Astronomy 1
Since 2002 the National Aeronautics and Space Administration (NASA) has carried out an optical survey of the debris environment in the geosynchronous Earth‐orbit (GEO) region with the Michigan Orbital Debris Survey Telescope (MODEST) in Chile. The survey coverage has been similar for 4 of the 5 years allowing us to follow the orbital evolution of Correlated Targets (CTs), both controlled and un‐controlled objects, and Un‐Correlated Targets (UCTs). Under gravitational perturbations the distributions of uncontrolled objects, both CTs and UCTs, in GEO orbits will evolve in predictable patterns, particularly evident in the inclination and right ascension of the ascending node (RAAN) distributions. There are several clusters (others have used a “cloud” nomenclature) in observed distributions that show evolution from year to year in their inclination and ascending node elements. However, when MODEST is in survey mode (field‐of‐view ~1.3°) it provides only short 5‐8 minute orbital arcs which can only be fit under the assumption of a circular orbit approximation (ACO) to determine the orbital parameters. These ACO elements are useful only in a statistical sense as dedicated observing runs would be required to obtain sufficient orbital coverage to determine a set of accurate orbital elements and then to follow their evolution. Identification of the source(s) for these “clusters of UCTs” would be advantageous to the overall definition of the GEO orbital debris environment. This paper will set out to determine if the ACO elements can be used to in a statistical sense to identify the source of the “clustering of UCTs” roughly centered on an inclination of 12° and a RAAN of 345°. The breakup of the Titan 3C‐4 transtage on February 21, 1992 has been modeled using NASA’s LEGEND (LEO‐to‐GEO Environment Debris) code to generate a GEO debris cloud. Breakup fragments are created based on the NASA Standard Breakup Model (including fragment size, area‐to‐mass (A/M), and delta‐V distributions). Once fragments are created, they are propagated forward in time with a subroutine GEOPROP. Perturbations included in GEOPROP are those due to solar/lunar gravity, radiation pressure, and major geopotential terms. The question to be addressed: are the UCTs detected by MODEST in this inclination/RAAN region related to the Titan 3C‐4 breakup? Discussion will include the observational biases in attempting to detect a specific, uncontrolled target during given observing session. These restrictions include: (1) the length of the observing session which is 8 hours or less at any given date or declination; (2) the assumption of ACO elements for detected object when the breakup model predicts debris with non‐zero eccentricities; (3) the size and illumination or brightness of the debris predicted by the model and the telescope/sky limiting magnitude. ORBITAL DEBRIS Page 43 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Strategies for Optimizing GEO Debris Search K. H. Poole, J. P. Woloschek, E. H. Murphy, G. C. Lefever, J. P. Breslin Northrop Grumman Corporation An effective debris search strategy at GEO requires the balance of objectives that are often at odds with one another. Ideally, the strategy would allow for both high search rates (greater coverage, leak proof fence) and sufficient dwell times within a sensor’s individual pixel (greater sensitivity). In this study we simulate various search strategies to evaluate their effectiveness in meeting these two objectives. We initially evaluate three basic search strategies using a continuous scan: (1) one dimensional scans centered on the GEO belt, (2) one dimensional scans centered off the GEO belt and (3) a square wave scan pattern centered on the GEO belt. We evaluate each of these methods using various encounter statistics to determine which method provides the greatest coverage. We also investigate the possibility of minimizing solar phase angles during the search to achieve maximum sensitivities. Based on these results we focus on the one dimensional scans centered on the GEO belt. We analyze the effect on sensitivity and coverage of using a step stare method (both fixed and sidereal stares) rather than a continuous scan method. Included in this analysis is an assessment of a specialized step stare based on the method used by the ESA Space‐Debris Telescope on Tenerife, Canary Islands1. Lastly we look at the likelihood that satellites with high inclinations and/or drift rates (both typical characteristics of debris objects) will not stay in a sensor’s instantaneous field of view for the sensor’s full integration time. We developed analytical equations to (1) calculate the expected dwell time within a single pixel and (2) calculate the likelihood that a streak will dwell within a single pixel for the full integration time, given the relative angular rate of the satellite and the sensor detector size and integration time. An expected pixel dwell time that is less than the full integration time could be justification for reducing the integration time, which would result in a reduction of the duration of individual scans without sacrificing sensitivity. Results are presented for simulations that take into consideration the primary objectives of an effective GEO debris search and provide insight into methods for improved success. 1W. Flury, et al., “Searching for Small Debris in the Geostationary Ring – Discoveries with the Zeiss 1‐metre Telescope”, ESA Bulletin 104 – November 2000 Space Debris Optical Observation System in JAXA/IAT Dr. Atsushi Nakajima1, Mr. Hirohisa Kurosaki1, Mr. Taisei Fukaya2 Institute of Aerospace Technology (IAT), Japan Aerospace Exploration Agency (JAXA), 2Graduate Student of Tokyo Metropolitan University 1
For the development of the optical observation technologies for space debris, Institute of Aerospace Technology(IAT) of JAXA has prepared two small optical observation facilities of LEO and GEO debris detections. LEO debris tracking facility is located at HQ of JAXA, Tokyo, with a 35cm telescope onboard the 3‐axis tracking mount system, GEO debris observation facility is located at Nyukasa‐yama mountain in Nagano Prefecture. A 35cm Newtonian optical telescope with 2K2K CCD camera and a 25cm BRC optical telescope with 4K4K CCD camera are supported on each equatorial mount system. The latter facility is under construction and will be operated within this autumn. The altitude of this site is 1,860m and the optical environment will be adequate for detecting faint objects. One of the most important study item in our R&D is to develop an automatic small size GEO debris detection software. In usual case, a long exposure time is necessary to detect a faint object by accumulating weak light energy during the ORBITAL DEBRIS Page 44 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS time. On the contrary, short exposure observation is necessary for GEO debris detection to avoid the influence of the fixed star streaks image. We have proposed a stacking method for detecting a noise‐level faint GEO debris by accumulating the signals of a number of images, for example, a hundred frames. By applying the stacking method for asteroid survey observation, 21st magnitude asteroid can be detected by using this small telescope. Another research item is to develop a high‐speed read/write CCD camera. High efficiency back illuminated 1K1K and 2K2K CCD cameras were developed and 4K4K CCD camera is under testing. The read/write time of the 4K4K CCD camera is about 10 seconds, which is cooled by a sterling engine refrigerator. This paper introduces the JAXA’s facilities for LEO and GEO space debris observation and describes some developing technologies and evaluated results. In‐situ Observations of Space Debris at ESA Gerhard Drolshagen ESA/ESTEC/TEC‐EES Information on the small size (millimetre or smaller) space debris and meteoroid population in space can only be obtained by in‐situ detectors or the analysis of retrieved hardware. Past, ongoing and planned ESA activities in this field are presented. In 1996 the GORID impact detector was launched into a geostationary orbit on‐board the Russian Express‐2 telecommunication satellite. This impact ionisation detector had a sensor surface of 0.1 m2. Until July 2002 when the spacecraft was shut down it recorded more than 3000 impacts in the micrometre size range. Inter alia, GORID measured numerous clusters of events, believed to result from debris clouds, and indicated that debris fluxes in GEO are larger than predicted by present models. Another in‐
situ detector, DEBIE‐1, was launched in October 2001 and is operating on‐board the small technology satellite PROBA in a low polar orbit. It has two sensors, each of 0.01m2 size, pointing in different directions. A second detector of this type, DEBIE‐2 with 3 sensors, is ready for flight on the EuTEF carrier (external payload to ISS). The data from GORID and DEBIE‐1 are stored on‐line in EDID (European Detector Impact Database). Post‐flight impact analyses of retrieved hardware provide detailed information on the encountered meteoroid and debris fluxes over a large range of sizes. ESA initiated several analyses in the past ((EURECA, Hubble Space Telescope (HST) solar arrays). The most recent impact analysis was performed for the HST solar arrays retrieved in March 2002. Measured crater sizes in solar cells ranged from about 1 micron to 7 mm. A total of 175 complete penetrations of the 0.7 mm thick arrays were observed. A chemical analysis of impact residues allowed the distinction between space debris and natural meteoroids. Space debris was found to dominate for sizes smaller than 10 microns and larger than about 1 mm. For intermediate sizes impacts are mainly from meteoroids. Results of the analysis and comparisons with model predictions are presented. The paper concludes by presenting evidence for several unintended in‐situ impacts which were encountered by the CCDs of the XMM‐Newton x‐ray telescope. ORBITAL DEBRIS Page 45 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Reflectivity of NaK Droplets Carsten Wiedemann1, Michael Oswald1, Sebastian Stabroth1, Heiner Klinkrad2, Peter Vörsmann1 Institute of Aerospace Systems, Technische Universität Braunschweig, 2Space Debris Office, ESA/ESOC 1
An important contribution to the space debris population near 900 km orbital altitude are the NaK droplets. Sixteen nuclear powered satellites of the type RORSAT launched between 1980 and 1988 activated a reactor core ejection system close to this altitude. The core ejection causes an opening of the primary coolant circuit. The liquid coolant has been released into space during these core ejections, forming droplets up to a diameter of 5.5 cm. These droplets consist of an alloy of two alkali metals, sodium and potassium (NaK). In this paper the monochromatic and the total reflectivity of NaK is calculated using theoretical models. The reflectivity depends on the alloy composition and temperature of a droplet. The alloy composition may change due to evaporation, resulting in an enrichment of sodium especially at the droplet surface. According to the literature, there is only a limited number of available measurement data concerning the optical properties of NaK alloys. Furthermore the published data for pure sodium and potassium are controversial. Thus it is necessary to investigate the optical properties of alkali metals and their alloys. Mainly two types of optical absorption, the intraband and the interband absorption, are considered. The intraband absorption is calculated using the Drude‐model which uses electrical properties to derive the optical constants of pure metals or alloys. Drude assumes that the valence electrons can be treated as free electrons. The electrons behave like an ideal gas of uncharged particles. The theory of free electrons is a very simple model for the description of the valence electrons in metals. This assumption is sufficient for alkali metals, because they show a nearly free electron behavior. For the interband absorption the classical Butcher‐model is used. Furthermore an absorption anomaly which has been observed in some alkali metals is discussed. Especially for potassium, some measurements revealed an unexpected absorption in the visible and the near infrared. This absorption can be determined using a model according to Overhauser who assumes charge‐density waves (CDW). But the existence of the anomalous absorption is controversial. The influence of the different models on the reflectivity is discussed. The reflectivity is calculated depending on the alloy composition and the temperature at the surface of a droplet. The results are compared to measurement data from the literature. It is shown that NaK droplets have a very high total reflectivity. ORBITAL DEBRIS Page 46 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS The Early Development of Satellite Characterization Capabilities at the Air Force Laboratories John V. Lambert1, Kenneth E. Kissell2 The Boeing Company, Space and Intelligence Systems, 2Kissell Consultants 1
This presentation overviews the development of optical Space Object Identification (SOI) techniques at the Air Force laboratories during the two‐decade “pre‐operational” period prior to 1980 when the Groundbased Electro‐Optical Deep Space Surveillance (GEODSS) sensors were deployed. Beginning with the launch of Sputnik in 1957, the United States Air Force has actively pursued the development and application of optical sensor technology for the detection, tracking, and characterization of artificial satellites. Until the mid‐1980s, these activities were primarily conducted within Air Force research and development laboratories which supplied data to the operational components on a contributing basis. This presentation traces the early evolution of the optical space surveillance technologies from the early experimental sensors that led to the current generation of operationally deployed and research systems. The contributions of the participating Air Force organizations and facilities will be reviewed with special emphasis on the development of technologies for the characterization of spacecraft using optical signatures and imagery. The presentation will include descriptions and photographs of the early facilities and instrumentation, and examples of the SOI collection and analysis techniques employed. In this early period, computer support was limited so all aspects of space surveillance relied heavily on manual interaction. Many military, government, educational, and contractor agencies supported the development of instrumentation and analysis techniques. This overview focuses mainly on the role played by Air Force System Command and Office of Aerospace Research, and the closely related activities at the Department of Defense Advanced Research Projects Agency. The omission of other agencies from this review reflects the limitations of this presentation, not the significance of their contributions. Canadian Surveillance of Space Concept Demonstrator: Photometric Variability of Deep‐Space Objects, Analysis and Interpretation Bryce Bennett1, Thomas Racey1, Robert Scott2, and Brad Wallace2 Royal Military College of Canada, 2Defence R&D Canada 1
Defence R&D Canada (DRDC), in partnership with the Royal Military College of Canada, constructed a remotely operated, ground based optical observatory for deep space surveillance, inspired by the RAVEN model of the Maui Space Surveillance System. This sensor was first configured in 2000 and underwent satellite metric accuracy assessment in 2004. Recently, the sensor, located in Kingston, Ontario, was incorporated into the Canadian Surveillance of Space Concept Demonstrator. This paper presents the results of the analysis of CCD image data reduced to characterize the time dependence of the relative visible magnitudes of deep‐space objects. Various streak extraction algorithms were coded, enabling generation and subsequent analysis of the along‐track light‐curve of RSOs. The algorithms were tested on virtual data, and then used to examine Molniya‐class objects whose light‐
curves exhibit variability over the image exposure durations. Fourier analysis and other time‐series comparisons were performed on archived observations made over periods ranging from a single night to more than a year. The results indicate that the observed class of Molniya satellites are temporally resolvable in period of oscillation. The temporal periods appear stable over the initial analysis periods of up to 18 months. Current data will be presented to illustrate the stability of these light curves over the past 6 years. NON‐RESOLVED OBJECT CHARACTERIZATION Page 47 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Harmonic Structure Function Dr. R. David Dikeman, Staci Lin, Cecile Kim Lockheed Martin Hawaii Lockheed Martin Hawaii presents a novel signal processing algorithm for focal plane array processing. We introduce the Harmonic Structure Function (HSF) and demonstrate its capability in detecting, classifying and counting rotating bodies in a single pixel. The HSF has a powerful use in dynamical situations occurring on scales less than the single pixel solid angle. The work presented here is making a major impact in the Missile Defense Agency’s Project Hercules Forward Based Sensor (FBS) group but the results presented here is shown in an unclassified form. First, the HSF algorithm is detailed. The origin of the HSF is in the ASW (AntiSubmarine Warfare) acoustic processing domain and the analogy to the focal plane is given. Next, the mathematical definition of the HSF and the natural extension from integral to discrete form is detailed. Thereafter, additional harmonic processing techniques such as the so‐called ‘sidelobe’ reduction are explained. These techniques are powerful methods to determine the fundamental frequency of a given rotating body that can have various harmonically related narrow band tonal structures. Simulations of rotating bodies and modulating reflectance used for analysis are then discussed. These simulations result in the construction of time series data for N rotating bodies with fundamental frequencies f n in noisy backgrounds. The HSF is then used to analyze these fidelity simulations. It is shown that the HSF is capable of detecting, classifying and counting N objects on a single pixel. Finally, the robustness of the algorithm is analyzed and it is shown that the number of detectable objects is dependent on sample rate, target temporal extent, and other factors. This analysis yield important considerations for sensor developers and operators. Statistical Properties and Analysis of Photometric Signatures of Geos Tamara E. Payne1, Stephen A. Gregory1, Kim Luu2 1
Boeing LTS Inc., 2AFRL Abstract unavailable. Results of Satellite Brightness Modeling Using Kriging Optimized Interpolation Major Charity A. Weeden1, Matthew Hejduk2 1
Canadian Forces, NJ55X Policy and Doctrine, 2Titan Corp At the 2005 AMOS conference, Kriging Optimized Interpolation (KOI) was presented as a tool to model satellite brightness as a function of phase angle and solar declination angle (J.M Okada and M.D. Hejduk). Since November 2005, this method has been used to support the tasking algorithm for all optical sensors in the Space Surveillance Network (SSN). The satellite brightness maps generated by the KOI program are compared to each sensor’s ability to detect an object as a function of the brightness of the background sky and angular rate of the object. This will determine if the sensor can technically detect an object based on an explicit calculation of the object’s probability of detection. In addition, recent upgrades at Ground‐Based Electro Optical Deep Space Surveillance Sites (GEODSS) sites have increased the amount and quality of brightness data collected and therefore available for analysis. This in turn has provided enough data to study the modeling process in more detail in order to obtain the most accurate NON‐RESOLVED OBJECT CHARACTERIZATION Page 48 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS brightness prediction of satellites. Analysis of two years of brightness data gathered from optical sensors and modeled via KOI solutions are outlined in this paper. By comparison, geo‐stationary objects (GEO) were tracked less than non‐GEO objects but had higher density tracking in phase angle due to artifices of scheduling. A statistically‐significant fit to a deterministic model was possible less than half the time in both GEO and non‐GEO tracks, showing that a stochastic model must often be used alone to produce brightness results, but such results are nonetheless serviceable. Within the Kriging solution, the exponential variogram model was the most frequently employed in both GEO and non‐GEO tracks, indicating that monotonic brightness variation with both phase and solar declination angle is common and testifying to the suitability to the application of regionalized variable theory to this particular problem. Finally, the average nugget value, or prediction fidelity, was slightly better in the non‐GEO tracks than in GEO, often centering around half of a visual magnitude. In describing these relationships between modeling variables and a successful brightness solution, better predicted brightness values for use in operational tasking can be produced. MSSS Satellite Categorization Laboratory Ray Deiotte1, Mike Guyote1, Thomas Kelecy1, 2, Doyle Hall1, 2, John Africano1, 2, Paul Kervin3 The Boeing Company, Colorado Springs, Colorado, 2The Boeing Company, Kihei, Hawaii, 3Air Force Research Laoratory 1
The MSSS satellite categorization laboratory is a fusion of robotics and digital imaging processes that aims to decompose satellite photometric characteristics and behavior in a controlled setting. By combining a robot, light source and camera to acquire non‐resolved images of a model satellite, detailed photometric analyses can be performed to extract relevant information about shape features, elemental makeup, and ultimately attitude and function. Using the laboratory setting a detailed analysis can be done on any type of material or design and the results cataloged in a database that will facilitate object identification by “curve‐fitting” individual elements in the basis set to observational data that might otherwise be unidentifiable. Currently the laboratory has created, an ST‐Robotics five degree of freedom robotic arm, collimated light source and non‐focused Apogee camera have all been integrated into a MATLAB based software package that facilitates automatic data acquisition and analysis. Efforts to date have been aimed at construction of the lab as well as validation and verification of simple geometric objects. Simple tests on spheres, cubes and simple satellites show promising results that could lead to a much better understanding of non‐
resolvable space object characteristics. This paper presents a description of the laboratory configuration and validation test results with emphasis on the non‐resolved photometric characteristics for a variety of object shapes, spin dynamics and orientations. The future vision, utility and benefits of the laboratory to the SSA community as a whole are also discussed. AMOS Observations of NASA’s IMAGE Satellite Doyle Hall1, 2, John Africano1, 2, David Archambeault2, Brian Birge2, David Witte3, Paul Kervin4 The Boeing Company, Colorado Springs, Colorado, 2Boeing LTS/AMOS, Kihei, Hawaii, 3Pantera Consulting, 4Air Force Research Laboratory/DET15 1
Abstract unavailable. NON‐RESOLVED OBJECT CHARACTERIZATION Page 49 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Simulated Aging of Spacecraft External Materials on Orbit Sergei A. Khatipov Moscow State Engineering Physics Institute Moscow State Engineering Physics Institute (MIFI), in cooperation with Air Force Research Laboratory’s Satellite Assessment Center (SatAC), the European Office of Aerospace Research and Development (EOARD), and the International Science and Technology Center (ISTC), has developed a database describing the changes in optical properties of materials used on the external surfaces of spacecraft due to space environmental factors. The database includes data acquired from tests completed under contract with the ISTC and EOARD, as well as from previous Russian materials studies conducted within the last 30 years. The space environmental factors studied are for those found in Low Earth Orbits (LEO) and Geosynchronous orbits (GEO), including electron irradiation at 50, 100, and 200 keV, proton irradiation at 50, 150, 300, and 500 keV, and ultraviolet irradiation equivalent to 1 sun‐year. The material characteristics investigated were solar absorption (αS), spectral reflectance (ρλ), solar reflectance (ρS), emissivity (ε), spectral transmission coefficient (Tλ), solar transmittance (TS), optical density (D), relative optical density (D/x), Bi‐directional Reflectance Distribution Function (BRDF), and change of appearance and color in the visible wavelengths. The materials tested in the project were thermal control coatings (paints), multilayer insulation (films), and solar cells. The ability to predict changes in optical properties of spacecraft materials is important to increase the fidelity of space observation tools, better understand observation of space objects, and increase the longevity of spacecraft. The end goal of our project is to build semi‐empirical mathematical models to predict the long‐term effects of space aging as a function of time and orbit. Using Space Weathering Models to Match Observed Spectra to Predicted Spectra Michael Guyote1, Kira J. Abercromby2, Jennifer Okada1 Boeing, 2ESCG/Jacobs Sverdrup 1
Materials exposed to space weathering have exhibited marked spectral changes which include both a darkening and “reddening” of the spectra. For many years, we have conducted research into the physics behind these phenomena. This research (in the wavelength region of 0.4‐0.9 microns (um)) has been fruitful and has resulted in a graphics‐interface based application which produces expected spectra of materials which closely match observations. In addition, we have also established a link between basic physics of the optical properties of submicroscopic particles and the resulting spectra, and have implemented the first phase of a library of statistical analysis techniques designed to aid in object and material classification of ground‐based observations of space weathered materials. We are continuing to extend our research scope by increasing the wavelengths under consideration to include near‐infrared (0.4 ‐ 2.5 um). The research utilizes data fusion techniques to aid in linking the a priori information gained from basic physics to the observed phenomena and to aid in determining spectral features that are unique to a specific space weathering environment or material. The research team is also utilizing data fusion techniques coupled with an augmented graphical interface application which will allow development of a system of algorithms which will provide accurate prediction of (and accurate categorization of) space environmental spectral effects. NON‐RESOLVED OBJECT CHARACTERIZATION Page 50 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Comparisons of Ground Truth and Remote Spectral Measurements of the FORMOSAT and ANDE Spacecrafts Kira J. Abercromby1, Kris Hamada2, Jennifer Okada2, Michael Guyote2, Ed Barker3 ESCG/Jacobs Sverdrup, 2Boeing, 3NASA 1
Determining the material type of objects in space is conducted using laboratory spectral reflectance measurements from common spacecraft materials and comparing the results to remote spectra. This past year, two different ground‐truth studies commenced. The first, FORMOSAT III, is a Taiwanese set of six satellites to be launched in March 2006. The second is ANDE (Atmospheric Neutral Density Experiment), a Naval Research Laboratory set of two satellites set to launch from the Space Shuttle in November 2006. Laboratory spectra were obtained of the spacecraft and a model of the anticipated spectra response was created for each set of satellites. The model takes into account phase angle and orientation of the spacecraft relative to the observer. Once launched, the spacecraft are observed once a month to determine the space aging effects of materials as deduced from the remote spectra. Preliminary results will be shown of the FORMOSAT III comparison with laboratory data and remote data while results from only the laboratory data will be shown for the ANDE spacecraft. Satellite Characteristics with uvbyHβCa Photometry Nancy Hamilton National Security Agency A satellite’s spectrum has two contributions: reflected sunlight and its own blackbody radiation. The extended Strömgren system, uvbyHβCa, is proposed as a self‐calibrating method of subtracting out the sunlight. While the blackbody radiation contribution will be weak, it will not have the Hβ and Ca II H and K absorption features. It is argued here that the signal‐to‐noise ration of the blackbody radiation to the solar radiation may be detectable, and that information used for satellite characterization. The uvby bands will characterize the reflected sunlight and that model can be extended to the standard profile of the Hβ and Ca II H and K absorption lines. Any excess radiation in the absorption lines could be from the blackbody emission of the satellite. This proposed method is suited for the Haleakala 3.67m telescope since multiple coudé feeds can be used for simultaneous narrow‐band photometry at various altitudes of observation. Calibration stars in this system are available, but not needed during the observation. The relative strength of the blackbody emission to the sunlight will depend on unique features of the satellite. Models of blackbody radiation detection will be presented. NON‐RESOLVED OBJECT CHARACTERIZATION Page 51 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS 3 ‐ 13 μm Spectra of Geosynchronous Satellites David K. Lynch1, Ray W. Russell1, Richard J. Rudy1, David Gutierrez1, Mark Turpin1, Kirk Crawford1, Yaniv Dotan1, Daryl Kim1, Mark A. Skinner2 The Aerospace Corporation, 2The Boeing Company/AMOS 1
We report 3‐13 μm spectra of three geosynchronous satellites using The Aerospace Corporation’s Broadband Array Spectrograph System (BASS) on the AEOS 3.7 meter telescope at Haleakala in December 2005. The satellites observed were NORAD 21639 (TDRS 5), 11145 (DSCS 2‐12) and 15629 (INTELSAT 510). The spectra showed structure indicative of the satellites’ surface material, temperature and cross section as viewed from the observatory. A brief summery of how to analyze such spectra to retrieve surface material composition, temperature and geometrical cross section is included. Algorithms for Hyperspectral Endmember Extraction and Signature Classification with Morphologial Dendritic Networks Mark S. Schmalz, Gerhard X. Ritter Center for Computer Vision and Visualization, University of Florida Accurate multispectral or hyperspectral signature classification is key to the nonimaging detection and recognition of space objects. Additionally, signature classification accuracy depends on accurate spectral endmember determination [1]. Previous approaches to endmember computation and signature classification were based on linear operators or neural networks (NNs) expressed in terms of the algebra (R, +, x) [1,2]. Unfortunately, class separation in these methods tends to be suboptimal, and the number of signatures that can be accurately classified often depends linearly on the number of NN inputs. This can lead to poor endmember distinction, as well as potentially significant classification errors in the presence of noise or densely interleaved signatures. In contrast to traditional CNNs, autoassociative morphological memories (AMM) are a construct similar to Hopfield autoassociatived memories defined on the (R, +, ∨,∧) lattice algebra [3]. Unlimited storage and perfect recall of noiseless real valued patterns has been proven for AMMs [4]. However, AMMs suffer from sensitivity to specific noise models, that can be characterized as erosive and dilative noise. On the other hand, the prior definition of a set of endmembers corresponds to material spectra lying on vertices of the minimum convex region covering the image data. These vertices can be characterized as morphologically independent patterns. It has further been shown that AMMs can be based on dendritic computation [3,6]. These techniques yield improved accuracy and class segmentation/separation ability in the presence of highly interleaved signature data. In this paper, we present a procedure for endmember determination based on AMM noise sensitivity, which employs morphological dendritic computation. We show that detected endmembers can be exploited by AMM based classification techniques, to achieve accurate signature classification in the presence of noise, closely spaced or interleaved signatures, and simulated camera optical distortions. In particular, we examine two critical cases: (1) classification of multiple closely spaced signatures that are difficult to separate using distance measures, and (2) classification of materials in simulated hyperspectral images of spaceborne satellites. In each case, test data are derived from a NASA database of space material signatures. Additional analysis pertains to computational complexity and noise sensitivity, which are superior to classical NN based techniques. NON‐RESOLVED OBJECT CHARACTERIZATION Page 52 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS [1] Winter, M.E. “Fast autonomous spectral end‐member determination in hyperspectral data,” in Proceedings of the 13th International Conference On Applied Geologic Remote Sensing, Vancouver, B.C., Canada, pp. 337‐44 (1999). N. Keshava, “A survey of spectral unmixing algorithms,” Lincoln Laboratory Journal 14:55‐78 (2003). Ritter, G.X., L. Iancu, and G. Urcid, “Morphological perceptrons with dendritic structure,” in Proceedings of the 2003 IEEE Conference on Fuzzy Systems, pp. 1296‐1301 (2003). Grana, M. , P. Sussner, and G.X. Ritter. “Associative morphological memories for endmember determination in spectral unmixing”, Proceedings of the 12th IEEE International Conference on Fuzzy Systems 2: 1285‐1290 (2003). Ritter, G.X., L. Iancu, and M.S. Schmalz, “A new auto‐associative memory based on lattice algebra,” in Proceedings of the Ninth Iberoamerican Congress on Pattern Recognition, Puebla, Mexico, pp. 148‐55 (2004). Ritter, G.X. and M.S. Schmalz. “Learning in lattice neural networks that employ dendritic computing”, to appear in Proceedings of the 2006 IEEE World Congress on Computational Intelligence (in publication). [2] [3] [4] [5] [6] Science Applications of the RULLI Camera: Photon Thrust, General Relativity and the Crab Nebula Douglas G. Currie1, David C. Thompson2, Steven E. Buck2, Rose P. des Georges2, Cheng Ho2, Dennis K. Remelius2, Bob Shirey2, Thomas Gabriele3, Victor L. Gamiz3, Laura J. Ulibarri3, Marc R. Hallada4, Paul Szymanski4 Department of Physics, University of Maryland, 2Los Alamos National Laboratory, 3Air Force Research Laboratory, 4Schafer Corporation 1
RULLI (Remote Ultra‐Low Light Imager) is a unique single photon imager with very high (microsecond) time resolution and continuous sensitivity, developed at Los Alamos National Laboratory. This technology allows a family of astrophysical and satellite observations that were not feasible in the past. We will describe the results of the analysis of recent observations of the LAGEOS II satellite and the opportunities expected for future observations of the Crab nebula. The LAGEOS/LARES experiments have measured the dynamical General Relativistic effects of the rotation of the earth, the Lense‐Thirring effect. The major error source is photon thrust and a required knowledge of the orientation of the spin axis of LAGEOS. This information is required for the analysis of the observations to date, and for future observations to obtain more accurate measurements of the Lense‐
Thirring effect, of deviations from the inverse square law, and of other General Relativistic effects. The rotation of LAGEOS I is already too slow for traditional measurement methods and Lageos II will soon suffer a similar fate. The RULLI camera can provide new information and an extension of the lifetime for these measurements. We will discuss the 2004 LANL observations of LAGEOS at Starfire Optical Range, the unique software processing methods that allow the high accuracy analysis of the data (the FROID algorithm) and the transformation that allows the use of such data to obtain the orientation of the spin axis of the satellite. We are also planning future observations, including of the nebula surrounding the Crab Pulsar. The rapidly rotating pulsar generates enormous magnetic fields, a synchrotron plasma and stellar winds moving at nearly the velocity of light. Since the useful observations to date rely only on observations of the beamed emission when it points toward the earth, most descriptions of the details of the processes have been largely theoretical. The RULLI camera’s continuous sensitivity and high time resolution should enable better signal to noise ratios for observations that may reveal properties like the orientation of the rotational and magnetic axes of the pulsar, the temperature, composition and electrical state of the plasma and effects of the magnetic field. NON‐RESOLVED OBJECT CHARACTERIZATION Page 53 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Hyperspectral H V Polarization Inverse Correlation David Maker Photon Research Associates This technique incorporates Horizontal and Vertical (H&V) polarization hyperspectral techniques in the infrared for target discrimination. Normally polarization provides an impediment to target discrimination because of the uncertainties in polarized background illumination. Here the polarization provides a definite aid in target discrimination even if the spectrum and intensity of the target and background are the same. In that regard negative images are approximately equivalent to taking the stretched reciprocal of Fresnel coefficient terms. Note in the emissive Fresnel coefficients there is a difference numerator (e.g., A‐B ≈ f(∆n’,i)≡cosi‐n’cosi) instead of A+B) emissive that ends up in these two denominators if the image is negative. In the near infrared (2‐5 microns) we also need an additional ROI V and image H polarization components negative image correlation because of strong surface roughness wavelength angular ‘i’ dependence and the often weak wavelength dependence of n’. These two difference denominators created in this way then have many more possibilities of zeros and higher correlation between emissive ROI and emissive target elements in the image. The main application here is in discriminating thermally thick (emissive) from thermally thin (reflective) targets even given the same spectrum and intensity. The technique has already been tested on ground targets and shown to work and could discriminate balloons from RVs as well since balloons are reflective and RVs emissive in the near infrared. This method allows accurate appraisal of whether such targets are thermally thick. NON‐RESOLVED OBJECT CHARACTERIZATION Page 54 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Risk Reduction Activities for the Near‐Earth Object Surveillance Satellite Project Donald Bédard1, Lauchie Scott1, Dr. Brad Wallace1, William Harvey2 Defence R&D Canada, 2Canadian Space Agency 1
The Near‐Earth Object Surveillance Satellite (NEOSSat) is a joint project between Defence Research and Development Canada (DRDC) and the Canadian Space Agency (CSA). The NEOSSat project will develop a multi‐mission micro‐satellite bus that is expected to satisfy two concurrent missions: detection and tracking near‐Earth asteroids (Near Earth Space Surveillance: NESS) and obtaining metric information on deep‐space satellites (High Earth Orbit Surveillance System: HEOSS). The former will use NEOSSat’s 15 cm diameter space telescope to discover and determine the orbits of inner Earth orbit (IEO) near‐earth objects (NEOs) that cannot be easily observed from the ground. For its part, the HEOSS mission will demonstrate that a micro‐satellite can be employed to produce surveillance of space (SofS) metric data of artificial earth‐orbiting objects having orbital altitudes between 15,000 and 40,000 km having sufficient quality to be accepted by the U.S. Space Surveillance Network. As a risk reduction effort for the NEOSSat project, a joint satellite tracking experiment was conducted by DRDC, CSA, the University of British Columbia and Dynacon using the MOST (Microvariability Oscillations of STars) microsatellite. MOST conducts precision photometric observations of bright stars and does not usually image starfields, but in October 2005, MOST returned Canada’s first space based satellite tracking observations of two GPS spacecraft. Good quality metric tracking data were obtained despite the fact MOST was not designed to image, let alone attempt satellite tracking. The observations also provided an estimate of the targeted satellite brightness and the results were consistent with ground based V‐band observations. These results demonstrate the soundness of the NEOSSat concept and the feasibility of the HEOSS mission. The nature of both science missions will require the NEOSSat sensor to be pointed to a different position in the sky on average every five minutes, with a goal of every three minutes, for an average of 288 images for every 24 hours of operation. To ensure both science teams can employ the NEOSSat spacecraft to its full potential, the Mission Planning System (MPS) will automate the scheduling of both the HEOSS and NESS observation tasks. In another risk reduction effort for the NEOSSat project, a prototype of the MPS software has been developed to help in the definition of the system requirements as well as to identify and reduce the risks associated with the development of this software system. The paper will first provide an update on the status and schedule of the NEOSSat project. Then, we will present the results achieved (metrics and photometry) from the two tracked GPS spacecraft as well as the lessons learned that are being applied during the development of the joint DRDC and CSA NEOSSat micro‐satellite. Finally, results obtained from the MPS prototype development will be presented with a special emphasis on the final system to be designed including a description of the functions judged to be critical based upon the risk reduction activity. SATELLITE METRICS Page 55 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS EOS Space Debris Tracking using High Power Lasers Craig Smith and Ben Greene EOS Space Systems Electro Optic Systems (EOS) has recently demonstrated an operational capability of a laser tracking system that can provide precision orbit determination for non‐compliant orbital debris objects. The system provides significant new capability in the precision of orbit determination, the size of objects tracked, and system capacity. This capability is being developed into a network of active tracking stations that are able to expand upon the existing catalog of satellites and debris objects that are currently routinely tracked. The expanded catalogue will be of value in Space Surveillance and Space Situational Awareness for both civilian and defense use of Low Earth Orbital space. Phoenix Upgrades in Support of Real‐Time Space Object Capture and Handoff at AMOS Bryan Law1, Tom Kelecy1, Andrew Alday1, Jake Barros1, Dennis Liang 1, Paul Sydney1, John Africano1, Paul Kervin2 Boeing LTS, 2AFRL Air Force Maui Optical and Supercomputing Site 1
As the population of space objects continues to grow, so does the interest in the development of Wide Field Of View (WFOV) optical sensors. Wide field of view capability greatly reduces the maximum time to search for and detect objects in coverage while greatly increasing our ability to survey space, and thus can provide a valuable resource to the space surveillance mission. Timely capture and hand‐off of “lost” or newly discovered objects between sensors is a key capability necessary for successful orbit characterization. The Air Force Maui Optical and Supercomputing (AMOS) site has refurbished a Baker‐
Nunn telescope, called Phoenix, with field‐flattening optics, a modern CCD camera, and control software similar to what is used in Raven telescopes. The result is a 6.8 degree by 6.8 degree field of view optical sensor. In addition to Phoenix, AMOS has developed a Raven‐class telescope with an approximate 0.5 degree by 0.5 degree field of view and has the capability of producing sub‐arcsecond metrics. This paper presents hardware and software upgrades that were made to the Phoenix telescope to support a near real‐time state vector hand‐off between sensors. The system performance requirements and calibration results are presented. The capture and hand‐off performance results will be used to outline requirements for an operational implementation. SATELLITE METRICS Page 56 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Proposal for a European Space Surveillance System – Results of an ESA Study T. Schildknecht1, T. Flohrer1, T. Michal2 1
Astronomical Institute, University of Bern, 2ONERA Space Surveillance denotes the task of systematically surveying and tracking all objects above a certain size and maintaining a catalogue with updated orbital and physical characteristics for these objects. Space Surveillance is gaining increased importance as the operational safety of spacecraft is depending on it. Currently, Europe has no capability for routine Space Surveillance covering all space regions of interest and is strongly depending on external information from the United States and Russia. A first design study for a European Space Surveillance System was initiated by ESA in 2002 and led by ONERA as prime contractor. This study proposed a preliminary system covering the LEO and GEO orbit regions including the required survey strategies allowing for the autonomous maintenance of a catalogue of orbital parameters (including cold start capability). For the surveillance of LEO objects with sizes larger than 10 cm, a bistatic UHF radar with a large field of view (20° in elevation and 180° in azimuth) and a long range (1500 km for a 10 cm sphere) was proposed, based on experience gained by the French GRAVES system. For the surveillance of GEO objects larger than 1 m, four sites equipped with survey and tasking telescopes were proposed. It was estimated that such a system would be capable to maintain the orbits of 98 % of the LEO objects and 95 % of the GEO objects contained in the USSTRATCOM catalogue. A subsequent study analyzed the feasibility of a UHF radar and proposed solutions for the surveillance of the MEO region by optical sensors. In fact, this region in space will soon gain major importance for Europe due to the deployment of the GALILEO navigation satellite system. SATELLITE METRICS Page 57 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Large Optical Glass Lenses for ELTs Dr. Peter Hartmann1, Arnie Bazensky2, Stephen Sokach2 1
Schott AG, 2Schott North America‐Optics for Devices ELTs will need large optical lenses for imaging optics and atmospheric dispersion correctors. The extreme dimensions of lenses considered in designs at present (up to 1.7 m diameter) pose severe challenges for the specification, production and inspection of the glass blanks. Possible maximum sizes, their very long production time, technical and economical conditions and probable restrictions are discussed. The inspection of glass blanks for ELT transmission optics can rely on methods already introduced for optical glass blanks of conventional sizes and for large mirror blanks of the glass‐ceramic ZERODUR(r) for most of their properties. However, especially for the refractive index homogeneity a scale‐up still has to be achieved. At present largest homogeneity interferometers have apertures about 500 to 600 mm. The development of larger ones is very time consuming, about 2 ‐3 years. There is a need for a close agreement on the required capability of the measurement method between the optical designers and the supplier and to start soon with this since the optical lenses may turn out to be more critical in production than the segments for the primary mirrors. Parallel Particle Swarm Optimization Brian Birge Boeing, LTS Particle Swarm Optimization (PSO) is a stochastic evolutionary Computational Intelligence (CI) algorithm taking influence from social behavior. It has been shown to be an excellent tool for finding optima of complex nonlinear hyperspaces as well as investigating Emergence concepts. Though resistant to local minima it can be computationally expensive in terms of time. As a population based algorithm, it makes an excellent candidate for parallelization. A parallel PSO Matlab variant has been developed to run on the Maui High Performance Computing clusters as well as desktop workstations. Scalability and speedup are examined as the algorithm is applied to various benchmark functions and used to train a feed forward neural network function approximator. Statistics of Short Term seeing at AEOS L. William Bradford, Lewis C. Roberts, Jr, Mark. A. Skinner The Boeing Company We have made measurements with the AEOS Visible Imager camera and with the AEOS adaptive optics wavefront sensor that allow us to estimate the value of Fried’s parameter r0 which can be directly related to the seeing. Wavefront sensor slope data is analyzed using Fried’s differential angle of arrival equations, and the Visible Imager data is analyzed using the a relationship between the Full Width at Half Maximum of a star’s “seeing disk” and r0. The wavefront sensor data sets will typically have 2000 measurements in 2 seconds. The Visible Imager measurements are about 100 images at intervals of 0.5 to 2 seconds. POSTER PRESENTATIONS Page 58 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS We are particularly interested in how much one measurement may differ from the preceding or the next measurement and in how much that variability varies with the seeing itself. This is of interest to modelers of adaptive optical systems, who in the past relied on models that have fixed values of r0. The data may also prove useful for setting error bounds on image processing algorithms that assume a fixed seeing over a data set. High Performance Computing Software Applications for Space Situational Awareness Concetto Giuliano1, Paul Schumacher1, Charles Matson1, Francis Chun1, Bruce Duncan2, Kathy Borelli2, Robert DeSonia2, George Gusciora2, Kevin Roe2 1AFRL/DE, 2MHPCC The High Performance Computing Software Applications Institute for Space Situational Awareness (HSAI‐SSA) has completed its first full year of applications development. The emphasis of our work in this first year was in improving space surveillance sensor models and image enhancement software. These applications are the Space Surveillance Network Analysis Model (SSNAM), the Air Force Space Fence simulation (SimFence), and physically constrained iterative de‐convolution (PCID) image enhancement software tool. Specifically, we have demonstrated order of magnitude speed‐up in those codes running on the latest Cray XD‐1 Linux supercomputer (Hoku) at the Maui High Performance Computing Center. The software applications improvements that HSAI‐SSA has made, has had significant impact to the warfighter and has fundamentally changed the role of high performance computing in SSA. Analysis of the Atmospheric Impact on the Analysis of Hyperspectral Imagery Joseph Coughlin Master Solutions The utility of spectral imagery to extract meaningful information from satellite signatures has been widely debated. We are studying the effect of improving atmospheric retrievals on the determination of material properties from hyperspectral and ultraspectral satellite signatures. The objective of this study is to reduce the impact of the atmosphere on spectral signatures and improve material identification. We simulate the atmospheric radiance and transmission components for different atmospheric conditions and analyze the effect of the atmosphere on the satellite spectral signatures. We perform these calculations at high spectral resolution using a line‐by‐line radiative transfer algorithm which we have developed. We simulate spectral signatures for different satellite models and lighting conditions in the VIS/NIR and LWIR spectral regions. We model different material mixtures, sensor characteristics, and optical blurring conditions and perform simplified spectral matching calculations for material identification. The initial results indicate that an ability to finely define the atmosphere can lead to promising material determinations even under poor conditions. The results of our atmospheric and satellite signature modeling efforts, material identification analyses and the trade‐space calculations are presented. POSTER PRESENTATIONS Page 59 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS The Skygrid Project – A Calibration Star Catalogue for DoD Sensors Stephen A. Gregory1, Tamara E. Payne1, John L. Africano1, Paul Kervin2 1
Boeing LTS Inc., 2AFRL Abstract unavailable. Environmental Space Situation Awareness and Joint Space Effects Lt Col Kelly J. Hand, Col Martin France Air Force Space Command It is well known that successful military operations rely on our ability to effectively integrate weather information into the planning and execution of land, air and sea operations. What is not so well known are the implications of environmental effects on space capabilities and the subsequent impact on the delivery of joint space effects to the warfighter. This paper provides an overview of the how space systems and missions are impacted by the environment and how AFSPC plans to effectively integrate environmental effects information into space operations in the context of Space Situational Awareness (SSA) and delivery of space effects to the warfighter. The desired end state of environmental SSA is the effective application of environmental SSA information—that is, to mitigate negative impacts on and improve performance of our space systems, and exploit potential space environment impacts on enemy systems. SSA is foundational to the success of the space superiority mission and effectively characterizing environmental effects is a critical part of that foundation. Space superiority operations ensure the continued delivery of space force enhancement to the military campaign, while denying those same advantages to the enemy. When SSA is successfully and sufficiently achieved, example results are a maintenance of space superiority, reduced “Fog of War” for commanders, lowered risk of space fratricide, rapid assessment of attacks on all blue, gray, or red space systems, and a shortened kill chain and targeting cycle. From a Defensive Counterspace (DCS) perspective, confirming or eliminating the environment as a factor enables us to respond in a much more effective way to protect our systems. From an offensive perspective, superior knowledge provides potential to exploit environmental effects on enemy space capabilities. To achieve a credible environmental SSA capability requires a system of systems (SoS) approach that includes three system components. Like a three legged stool, all legs are needed. This paper presents an overview of these critical components that needed to assure viable environmental SSA well into the 21st century. Combining Data from Multiple Telescopes to Improve the Resolution of Imagery Degraded by Atmospheric Turbulence Douglas Hope1, Stuart M. Jefferies1, 2 Institute for Astronomy, University of Hawaii, 2Steward Observatory, University of Arizona 1
The resolution of ground‐based imagery of satellites and other astronomical targets depends on the aperture size, the amount of atmosphere turbulence‐induced noise, the detector sampling and noise. Though large apertures offer the possibility of high‐resolution imagery, the blur caused by the atmosphere usually limits resolution to that of a telescope with an aperture diameter commensurate with POSTER PRESENTATIONS Page 60 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS the value of r0, typically 20 cm or less. One method for improving this situation is to use adaptive optics (AO) to compensate for the turbulence‐induced noise. As the AO compensation is never complete, further improvements to image quality can be obtained by using post‐processing methods such as multi‐frame blind deconvolution (MFBD). This type of algorithm simultaneously estimates the random blur function, caused by the atmosphere, and the target object. We propose a modified form of MFBD that combines data from an inhomogeneous set of telescope apertures. Of particular interest is whether one can combine data from a single large aperture telescope with data obtained from a set of smaller telescopes to improve the image resolution, such that it is greater than what would have been achieved by the single high‐resolution telescope. This work is supported by AFOSR awards F9550‐06‐1‐0179 and F49620‐02‐1‐0107. Linear Mode Photon Counting LADAR Camera Development for the Ultra‐Sensitive Detector Program1 Dr. Michael Jack1, Steve Bailey1, John Edwards1, Robert Burkholder1, Kanon Liu1, James Asbrock1, Valerie Randall1, George Chapman1, Dr. Jim Riker2 1
Raytheon Vision Systems, 2Air Force Research Laboratory, Directed Energy Directorate, DET 15 Advanced LADAR receivers enable high accuracy identification of targets at ranges beyond standard EOIR sensors. Increased sensitivity of these receivers will enable reductions in laser power, hence more affordable, smaller sensors as well as much longer range of detection. Raytheon has made a recent breakthrough in LADAR architecture by combining very low noise ~ 30 electron front end amplifiers with moderate gain >60 Avalanche Photodiodes. The combination of these enables detection of laser pulse returns containing as few as one photon up to 1000s of photons. Because a lower APD gain is utilized the sensor operation differs dramatically from traditional ʺgeiger mode APD” LADARs. Linear mode photon counting LADAR offers advantages including: determination of intensity as well as time of arrival, nanosecond recovery times and discrimination between radiation events and signals. In our talk we will review the basic amplifier and APD component performance, the front end architecture, the demonstration of single photon detection using a simple 4 x 4 SCA and the design of a fully integrated photon counting camera under development in support of the Ultra‐Sensitive Detector (USD) program sponsored by the Air Force Research Laboratory at Kirtland AFB, NM. Work Supported in Part by AFRL – Contract # FA8632‐05‐C‐2454 Dr. Jim Riker Program Manager 1
Observation, Prediction, and Modeling Atmospheric Structure Effects on EO/IR Systems Michael J. Kendra1, James M. Griffin1, Hilary E. Snell1, Delia Donatelli2, James H. Brown2 Atmospheric and Environmental Research, 2Air Force Research Laboratory/VSBYB 1
EO/IR sensors observing the battlespace environment through the earth’s atmosphere can be adversely affected by spatial and temporal variations in atmospheric radiance and transmission along the sensor line of sight (LOS). The physics of stochastic fluctuations is largely understood, and the radiation transport theory and models that include stochastic effects exhibit high fidelity when compared to corresponding sensor measurements. Deterministic structure is not as well understood, however, and the associated radiance levels and variability are often significantly higher than those of the benign, POSTER PRESENTATIONS Page 61 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS stochastic background. Since the radiance measured by the sensor comes from both the object of interest and the radiating atmosphere and it can also be attenuated by the atmosphere along the optical path, atmospheric structure and clutter affect target acquisition, identification, discrimination, and tracking in ways that are difficult to assess. We ranked MSX SPIRIT III radiometer measurements by radiance and clutter levels for a number of altitudes and sensor bands, and the atmospheric phenomena responsible for elevated levels were identified. Many of these high altitude atmospheric structures are not included in current IR radiance codes, and we describe recent efforts to extract and characterize these features using models such as MODTRAN, SHARC, and SAMM2. Our process involves identifying scenes with suitable structure, determining ambient model background conditions for a sufficiently large number of runs where the sensor, line of sight, and geophysical conditions are duplicated, and extracting radiance enhancements due to this structure on a pixel by pixel basis. We present a number of examples where extraction techniques have been successfully applied to scenes from the MSX SPIRIT III radiometer, including phenomena such as aurora, polar mesospheric clouds (PMC), and stratospheric warmings. The extracted structure features are then recombined with new ambient model background scenes such that they are properly located in the global/geophysical environment, accounting for the dependence of specific types of atmospheric structure on time, latitude, and season, in order to ensure real world fidelity. There are several limitations to this approach, so we used existing model capabilities to address these limitations. In the case of aurora, we show how auroral observations in the infrared by the MSX SPIRIT III radiometer can be used to determine valid model inputs. In the case of stratospheric warmings, we use measured scenes to determine stratospheric temperature enhancements. We demonstrate that proper combination of validated model inputs allows simulation of complex scenes in a real world context, and that prediction can be extended to other IR bands. The goal of this effort is to develop real time nowcast and forecast capability to estimate EO/IR sensor impairment levels on SSA systems due to geophysical effects on atmospheric structure, and we will discuss plans to develop real time data assimilation capabilities to support operational application. Observational and Modeling Study of Mesospheric Bores P.J. Loughmiller1, M.C. Kelley1, M.P. Hickey2 School of Electrical and Computer Engineering, Cornell University, 2Department of Physical Sciences, Embry‐Riddle Aeronautical University 1
In our studies of the dynamics of the upper atmosphere, some of the most intriguing mesospheric phenomena we observe high over the Hawaiian night skies are internal bores. These events affecting chemiluminescence are documented in monochromatic airglow images taken by high performance all‐
sky CCD imaging systems operating at the Maui Space Surveillance Site on top of Haleakala Crater. Data is collected as part of the ongoing, collaborative Maui ‐ Mesosphere and Lower Thermosphere (MALT) campaign, jointly sponsored by the National Science Foundation and the Air Force Office of Scientific Research. Bolstered by the Maui‐MALT dataset, several theories now exist for mesospheric bores, agreeing in principle that they are likely nonlinear structures spawned by gravity waves and propagating within ducted waveguide regions, such as thermal inversion layers. A new investigation will model optical emissions using a robust, time‐dependent, chemical dynamics model to explore the airglow response to ducted gravity waves and, in turn, the geographical and vertical coupling relationships which may exist. POSTER PRESENTATIONS Page 62 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Space Situation Awareness Integration Office Overview and Spiral 2 Results Jeffrey A. Marshall, Craig Z. Lowery and David S. Newton Space Situation Awareness Integration Office Space Situation Awareness (SSA) is defined as ʺThe requisite current and predictive knowledge of space events, threats, activities, conditions, and space systems status, capabilities, constraints, and employment to enable commanders, decision makers, planners and operators to gain and maintain freedom of action in space through the spectrum of conflict.ʺ The Space Situation Awareness Integration Office (SSAIO) responsibilities include: establishing and recommending overall direction for the nation’s SSA capabilities, capturing national SSA requirements, building the national SSA Enterprise Architecture (EA), evaluating capabilities to satisfy requirements, and evolving modernization plans and investment strategies. Monitoring and characterizing the natural environment is foundational to achieving SSA and is SSA Capability 1 of 15 capabilities defined in the SSAIO EA. This poster provides an overview of the SSAIO, the processes used to build and evaluate the SSA EA, and highlights some of the findings related to SSA Capability 1. Accelerating Scientific Computations using FPGAs Oliver Pell, Kubilay Atasu, Oskar Mencer Imperial College London Field Programmable Gate Arrays (FPGAs) are semiconductor devices that contain a grid of programmable cells, which the user configures to implement any digital circuit of up to a few million gates. Modern FPGAs allow the user to reconfigure these circuits many times each second, making FPGAs fully programmable and general purpose. Recent FPGA technology provides sufficient resources to tackle scientific applications on large‐scale parallel systems. As a case study, we implement the Fast Fourier Transform [1] in a flexible floating point implementation. We utilize A Stream Compiler [2] (ASC) which combines C++ syntax with flexible floating point support by providing a ‘HWfloat’ data‐type. The resulting FFT can be targeted to a variety of FPGA platforms in FFTW‐style, though not yet completely automatically. The resulting FFT circuit can be adapted to the particular resources available on the system. The optimal implementation of an FFT accelerator depends on the length and dimensionality of the FFT, the available FPGA area, the available hard DSP blocks, the FPGA board architecture, and the precision and range of the application [3]. Software‐style object‐
orientated abstractions allow us to pursue an accelerated pace of development by maximizing re‐use of design patterns. ASC allows a few core hardware descriptions to generate hundreds of different circuit variants to meet particular speed, area and precision goals. The key to achieving maximum acceleration of FFT computation is to match memory and compute bandwidths so that maximum use is made of computational resources. Modern FPGAs contain up to hundreds of independent SRAM banks to store intermediate results, providing ample scope for optimizing memory parallelism. At 175Mhz, one of Maxeler’s Radix‐4 FFT cores computes 4x as many 1024pt FFTs per second as a dual Pentium‐IV Xeon machine running FFTW (Figure 1). Eight such parallel cores fit onto the largest FPGA in the Xilinx Virtex‐4 family, providing a 32x speed‐up over performing the calculation in software. POSTER PRESENTATIONS Page 63 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Our work at Imperial combines the Maxeler cores with a high performance FPGA computing platform from HP to demonstrate the potential of FPGAs for scientific computing applications. Clearly, performance depends on the communication bandwidth to the FPGAs and we can clearly see in Figure 1 that PCI Express x4 is well matched with current FPGAs. Further activities focus on investigation of larger radices and optimizations for longer transform lengths. Figure 2 below shows that FPGAs with a single core are competitive for FFT transforms of more than 16 points by utilizing greater parallelism and reduced memory hierarchy overhead compared to CPUs. 12000
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M. Frigo and S. G. Johnson. The Design and Implementation of FFTW3. Proc. IEEE, 93(2), 2005. O. Mencer. ASC, A Stream Compiler for Computing with FPGAs. IEEE Trans. CAD, 2006. K. S. Hemmert, K. Underwood. An Analysis of the Dobule‐Precision Floating‐Point FFT on FPGAs. Proc. FCCM’05, IEEE Computer Society Press, 2005 POSTER PRESENTATIONS Page 64 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS The Effects of Scintillation on Non‐Redundant Aperture Masking Interferometry Lewis C. Roberts1, Jr., L. William Bradford1, Theo A. ten Brummelaar2, Nils H. Turner2 Mark A. Skinner1, Eric Therkildsen1, Ben R. Oppenheimer3, Andrew P. Digby3, Marshall D. Perrin4 The Boeing Company, 2The CHARA Array, 3Department of Astrophyics, American Museum of Natural History, 4University of California at Berkeley, Department of Astronomy 1
Non‐redundant aperture masking is a form of interferometry, where the aperture of the telescope is divided into two or more sub‐apertures. There is no need for path length equalization or the other complex equipment that is required for long‐baseline interferometry. The light from these subapertures interferes and details of the shape of the object can be determined by analyzing the resulting fringe patterns. We have collected pupil images with the AEOS telescope and use these real data to simulate the effects that variations in the amplitude of the incoming wavefront (ie. scintillation) has on the visibility measured by a two‐element aperture system. We find that scintillation has little effect on observations taken above 60 degrees elevation and what little effect there is can be calibrated out. At low elevations, the effects are more significant and harder to calibrate. Scintillation will have little effect on most astronomical imaging situations, but it will be a problem if the technique is used to observe fast moving low‐Earth satellites. Using Light Curves to Characterize Size and Shape of Pseudo‐Debris Heather M. Rodriguez1, Kira J. Abercromby1, Kandy S. Jarvis2 and Edwin Barker3 1
ESCG/Jacobs Sverdrup, 2ESCG/ Hamilton Sundstrand, 3NASA Johnson Space Center Photometric measurements were collected for a new study aimed at estimating orbital debris sizes based on object brightness. To obtain a size from optical measurements the current practice is to assume an albedo and use a normalized magnitude to calculate optical size. However, assuming a single albedo value may not be valid for all objects or orbit types and material type and orientation can mask an object’s true optical cross section. This experiment used a CCD camera to record data, a 300 W Xenon Ozone Free collimated light source to simulate solar illumination, and a robotic arm with five degrees of freedom to move the piece of simulated debris through various orientations. The pseudo‐debris pieces used in this experiment originate from the European Space Operations Centre’s ESOC2 ground test explosion of a mock satellite. A uniformly illuminated white ping‐pong ball was used as a zero‐
magnitude reference. Each debris piece was then moved through specific orientations and rotations to generate a light curve. This paper discusses the results of five different object‐based light curves as measured through an x‐rotation. Intensity measurements, from which each light curve was generated, were recorded in five degree increments from zero to 360 degrees. Comparing light curves of different shaped and sized pieces against their characteristic length establishes the start of a database from which an optical size estimation model will be derived in the future. POSTER PRESENTATIONS Page 65 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Hawaiian Atmospheric Forecasting utilizing the Weather Research and Forecast Model Kevin P. Roe1, Duane Stevens2 Maui High Performance Computing Center, 2Meteorology Department, University of Hawaii at Manoa 1
The Hawaiian Islands consist of large terrain changes over short distances, which results in a variety of microclimates in a very small region. Some islands have rainforests within a few miles of deserts; some have 10,000+ feet summits only a few miles away from the coastline. Because of this, weather models must be run at a much finer resolution to accurately forecast weather changes in these regions. NCAR’s Weather Research and Forecast Model (WRF) is run, on a nightly basis, using a coarse 54 km resolution grid (encompassing an area of approximately 7000 by 7000 km) nested down to a 2 km grid over each Hawaiian county. Since the computational requirements are high to accomplish this in a reasonable time frame (as to still be a forecast) WRF is run in parallel on MHPCC’s Cray 2.4 GHz Opteron based Linux system, “Hoku”. Utilizing 32 nodes (64 processors) the WRF model is run over the above conditions in approximately 4 hours. Although WRF forecast have only been in place for less than a year now, a lot of experience has gone behind its setup. MHPCC has been running NCAR’s Mesoscale Model version 5 (MM5) since 2000, which continues to be utilized by operators at the telescope facilities on Haleakala, Maui. Currently, the forecast produced is for a 48‐hour simulation, but will most likely be extended to a 72‐hour simulation; this forecast is available to operators by 8 AM and produces forecasts out until the next day at 8 PM. This is enough time to give operators and managers time to reschedule their operations if unacceptable conditions are predicted. The products we currently provide are: temperature, wind speed & direction, relative humidity, and rainfall. Additional products to be produced over Haleakala, include clear air turbulence, the Richardson number, and a measure of optical turbulence for the telescope operators using the Dewan and Jackson models. Beam Propagation Modeling Patrick Ryan Science Applications International Corporation Abstract unavailable. Lightcurve Signatures of Multiple Object Systems in Mutual Orbits Eileen V. Ryan and William H. Ryan Magadalena Ridge Observatory, New Mexico Institute of Mining and Technology The lightcurves of objects in mutual orbits will display occultation and/or eclipse events, collectively referred to as ‘mutual events’, under favorable geometric circumstances. Given that the unresolved image of a multiple object system is simply the sum of the scattered light from each individual object, these mutual events will appear as attenuations in the total detected light when one object (resulting in an occultation) or its shadow (resulting in an eclipse) passes in front of the other. Under certain geometric circumstances, it is possible to have both types of events occurring simultaneously, resulting in an even deeper minimum of the observed lightcurve. POSTER PRESENTATIONS Page 66 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS The identification of mutual event signatures in the lightcurves of asteroids has led to the detection of several asynchronous Near Earth Asteroid (Pravec et al. 2006) and Main Belt (Ryan et al. 2004, Warner et al. 2005, and Krugly et al. 2005) binary systems. Such asynchronous systems, where the rotation period of the primary object differs from the mutual orbital period of the system, usually display the most unambiguous signature of a binary system. Suspected binary systems where the primary’s rotational and the mutual orbit’s period are synchronous have also been observed (Behrend et al. 2004). However, the binary nature of these systems is more difficult to confirm since the signatures of the mutual events appear simply as more extended depressions in the minima already resulting from the asteroid’s rotation. Recently, there has been interest in identifying potentially hostile companions to artificial satellites. The detection of mutual events as described above is one possible method to accomplish this for non‐resolved systems. However, these companions will typically be much smaller relative to the parent body than previously observed asteroid binary systems, and hence, the expected attenuations due to the mutual events will be rather modest. Therefore, we will explore the parameter space of relative sizes, orbital dimensions, and surface characteristics, and report on the practicality of applying this technique to the detection of maneuvering microsatellite companions to artificial resident space objects. References: Behrend et al. (2004). (854) Frostia, IAU Circular 8389, (1089) Tama, IAU Circular 8265, (1313) Berna, IAU Circular 8292, and (4492) Debussy, IAU Circular 8354. Krugly et al. (2005). Binary main‐belt asteroid 11264 Claudiomaccone, presented at Dynamics and Physics of Solar System Bodies, May 22‐25, 2005, Kiev, Ukraine Pravec et al. (2006). Photometric survey of near‐Earth binary asteroids, Icarus 181, 63‐93 Ryan,W.H., E. Ryan, and C. Martinez (2004). 3782 Celle: Discovery of a Binary System within the Vesta Family of Asteroids. Planetary and Space Science, 52, 1093 ‐1101. Warner et al. (2005), (5905) Johnson, IAU Circular 8511 and (76818) 200 RG79, IAU Circular 8592 Training and Tactical Operationally Responsive Space Operations Barbara Sorensen1, Robert R. Strunce, Jr.2 U.S. Air Force Research Laboratory, 2Star Technologies Corporation 1
Current space assets managed by traditional space system control resources provide communication, navigation, intelligence, surveillance, and reconnaissance (ISR) capabilities using satellites that are designed for long life and high reliability. The next generation Operationally Responsive Space (ORS) systems are aimed at providing operational space capabilities which will provide flexibility and responsiveness to the tactical battlefield commander. These capabilities do not exist today. The ORS communication, navigation, and ISR satellites are being designed to replace or supplement existing systems in order to enhance the current space force. These systems are expected to rapidly meet near term space needs of the tactical forces. The ORS concept includes new tactical satellites specifically designed to support contingency operations such as increased communication bandwidth and ISR imagery over the theater for a limited period to support air, ground, and naval force mission. The Concept of Operations (CONOPS) that exists today specifies that in addition to operational control of the satellite, the tasking and scheduling of the ORS tactical satellite for mission data collection in support of the tactical warfighter will be accomplished within the Virtual Mission Operations Center (VMOC). This is very similar to what is currently being accomplished in a fixed Mission Operations Center on existing traditional ISR satellites. The VMOC is merely a distributed environment and the CONOPS POSTER PRESENTATIONS Page 67 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS remain virtually the same. As a result, there is a significant drawback to the current ORS CONOPS that does not account for the full potential of the ORS paradigm for supporting tactical forces. Although the CONOPS approach may be appropriate for experimental Tactical Satellites (TacSat), it ignores the issues associated with the In‐Theater Commander’s need to own and operate his dedicated TacSat for most effective warfighting as well as the Warfighter specific CONOPS. What is needed to realize the full potential of the ORS approach to the support of in‐theater tactical forces is the development of satellite tasking, interface, and data retrieval capabilities and mission operations approaches from a warfighter centered perspective, and the development of realistic training and simulation capabilities that will allow development, demonstration, and assessment of ORS tactical CONOPS. A system for Training and Tactical ORS Operations (TATOO) is currently being developed. This system will support development and evaluation of ORS specific CONOPS approaches, and training and evaluation of those CONOPS implementations through dedicated training capabilities, facilities, and exercises. TATOO will support the operational side of ORS and will merge with the revolutionary ORS spacecraft development and deployment processes to make the ORS paradigm a reality. TATOO’s primary objective is to support the In‐Theater Commander and Warfighter by developing, training, and assessing ORS mission CONOPS for In‐Theater tasking, scheduling, interface, and data retrieval for TacSats owned by In‐Theater Commanders. TATOO provides a laboratory/classroom environment for the development, test and evaluation of ORS Tactical Mission CONOPS for In‐Theater ORS operations. The TATOO laboratory will also be used to develop, evaluate, and document ORS Mission CONOPS for tactical ISR and other ORS missions. Within this framework, the laboratory/classroom can be used to develop the necessary training materials and procedures, as well as conduct training exercises that emphasize the training of In‐Theater personal with regard to: Tactical Ground Station Mission Operations; Tactical Operations for Mission Tasking and Scheduling; Tactical Mission Data Retrieval; and, Support for Warfighter Operations. Mobile Tracking Systems Using Large Reflective Telescopes Mr. Kyle Sturzenbecher1, Brad Ehrhorn2 1
Photo‐Sonics Inc., 2RC Optical Systems This paper is a discussion on the use of large reflective telescopes on mobile tracking systems with modern instrument control systems. Large optics can be defined as reflective telescopes with an aperture of at least 20 inches in diameter. New carbon composite construction techniques allow for larger, stronger, and lighter telescopes ranging from 240 pounds for a 20 inch, to 800 pounds for a 32 inch, making them ideal for mobile tracking systems. These telescopes have better light gathering capability and produce larger images with greater detail at a longer range than conventional refractive lenses. In a mobile configuration these systems provide the ability to move the observation platform to the optimal location anywhere in the world. Mounting and systems integration – We will discuss how large telescopes can be physically fit to the mobile tracking system and the integration with the tracking systems’ digital control system. We will highlight the remote control capabilities. We will discuss special calibration techniques available in a modern instrument control system such as star calibration, calibration of sensors. POSTER PRESENTATIONS Page 68 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Tracking Performance – We will discuss the impact of using large telescopes on the performance of the mobile tracking system. We will highlight the capabilities for auto‐tracking and sidereal rate tracking in a mobile mount. Large optics performance – We will discuss the advantages of two‐mirror Ritchey‐Chrétien reflective optics which offer in‐focus imaging across the spectrum, from visible to Long Wave Infrared. These zero expansion optics won’t lose figure or focus during temperature changes. And the carbon composite telescope tube is thermally inert. The primary mirror is a modern lightweight “dish” mirror for low thermal mass and is center supported/self balancing. Applications – We will discuss Visible ‐ IR Imaging requirements, Optical Rangefinders, and capabilities for special filters to increase resolution in difficult conditions such as viewing events through a fireball. We will review the performance characteristics of reflective telescopes in TSPI and IR imaging applications. Neutral Density Measurements Using In‐flight Accelerometer Data AFOSR Grant FA9550‐06‐1‐0061 Byron D. Tapley, Minkang Cheng, John C. Ries and Srinivas Bettadpur University of Texas at Austin, Center for Space Research Predicting the orbits of space objects at low altitude requires an accurate model for the atmospheric neutral density. One of the problems is inadequate density measurement needed to improve the models for the thermosphere density changes in response to the EUV variability on different temporal scales, in particular during geomagnetic storms. The Gravity Recovery and Climate Experiment (GRACE) mission measures the Earthʹs gravity field from space, and the high accuracy SuperStar accelerometers are particularly well suited for exploring the neutral density variations and atmospheric winds. This data can be used to validate, and improve density estimates for orbit predictions. It can also be used to validate sensor measurements that yield density profiles, such as the NRL SULI on DMSP and GPS occultation measurements. The objective of this research is to examine the use of the very accurate accelerometer measurements for determining accurate density measurements and thermospheric wind fields. The research tasks include refinement of the error estimate of the GRACE spacecraft drag coefficient, and validation of the density estimates against geodetic satellite orbit analysis. Impact of Space Weather on Flash Memory Devices Scott W. Teare1, Stephen Bracht1, Darla LeBlanc1, John L. Meason2, Lindsay Quarrie2, Sergio R. Restaino3, Jonathan Andrews3,Christopher Wilcox3 Electrical Engineering Department, New Mexico Tech, 2Energetic Materials Research and Test Center, New Mexico Tech, 3Naval Research Laboratory, Remote Sensing Div 1
The space environment is hard on satellites, space craft and space stations, and particularly harsh on their supporting microelectronic components. The environmental effects are exacerbated as space systems require an emphasis on the use of light weight materials and components that provide little shielding against radiation. In the case of geosynchronous satellite orbits, the normal background radiation environment is composed of cosmic rays, protons and electrons. In these orbits, the most damaging radiation are cosmic rays and protons at energies greater that 30MeV, as these can easily penetrate the POSTER PRESENTATIONS Page 69 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS thin skin of space craft, and high energy electrons. Debris radiation generated from particle interactions with the space craft itself also creates problems for electronic devices. Qualifying microelectronics devices for use in space requires a detailed understanding of the space environment, both normal and abnormal patterns generated by solar phenomenon including coronal mass discharge and solar flares. The radiation environment is measured by various satellites presently in orbit providing a measure of the space weather on a moment by moment basis. While the environment for space weather can be artificially created and devices exposed at various rates and total doses, evaluating these devices can require a significant set of electronic test and evaluation equipment. The Microelectronics Testing and Technology Obsolescence Program (METTOP) at New Mexico Tech has been developed to provide the measurement facilities for modern electronic devices. Capabilities range from testing microprocessors and large memory devices to power and microwave devices. Combined with radiation facilities at the White Sands Missile Range, a complete testing and evaluation program has been developed. In this paper we report on recent tests of flash memory devices in an artificial space radiation environment that simulates the radiation levels experienced by devices in the orbits commonly used by GEOS satellites (35.8 Mm) and the International Space Station (0.400 Mm) and evaluates the performance of flash memory devices under several characteristic rates and total dose conditions. These results demonstrate the suitability of the METTOP facility for testing microelectronic devices. This facility is able to support both commercial and government testing.
Adaptive Optics Survey of O Stars using AEOS Nils H. Turner1, Theo A. ten Brummelaar1, Lewis C. Roberts, Jr. 2, Douglas R. Gies3, Brian D. Mason4, William I. Hartkopf4 The CHARA Array, c/o Mount Wilson Observatory, 2The Boeing Company, 3Georgia State University, 4USNO 1
O stars are the most massive and luminous main sequence stars in the sky. They are frequently found in clusters of other O and B type stars. Due to the intrinsic brightness of these stars and their typical large distances, physical companions found by traditional techniques (spectroscopy, speckle interferometry, etc.) tend to be similar in mass and brightness to the primary. Adaptive optics observations allow one to probe for the fainter physical companions, further testing star formation scenarios and neighborhood conditions of O and B star clusters. We present the results of a multi‐year survey of O stars using AEOS, specifically searching for additional companions. Starting with a list of 171 O stars accessible to AEOS, we were able to observe 104 of these objects at least once, using the facility VisIm camera at I band. Under good atmospheric conditions, the analysis indicates that we can detect, and measure, a differential magnitude of at least 8 at I band, with indications that we may be doing better. Of these 104 systems, we have detected 38 new companions in 30 O star systems. We plan follow‐up measurements of these 30 systems at the V and R bands, using a different, lower noise CCD camera. POSTER PRESENTATIONS Page 70 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS The Developing Science and Technology List Raymond V Wick Institute for Defense Analyses The Militarily Critical Technologies Program (MCTP), a DoD responsibility directed by Congress, provides a systematic, ongoing assessment and analysis of goods and technologies to determine those technologies that would permit significant advances in the development, production and use of military capabilities of potential adversaries and those that are being developed worldwide that have the potential to significantly enhance or degrade US military capabilities in the future. The program’s objective is to characterize the technologies, including quantitative values and parameters, and assess worldwide technology capabilities. The MCTP is composed of two documents, the well known Militarily Critical Technology List (MCTL), and one called the Developing Science and Technologies List (DSTL). Both are products of the MCTP process. However, the DSTL is a compendium of scientific & technological capabilities being developed worldwide which have the potential to significantly enhance or degrade U.S. military capabilities starting five years into the future. The DSTL is sponsored by DDR&E and is used by other government organizations and agencies as well to aid in the prioritization and understanding of new technologies being developed worldwide. Working within an informal structure, TWG members are composed of government, industry and academia subject matter experts, who strive to produce objective analyses across each technology areas. This process and details of the current MCTP/DSTL are outlined in this poster paper. This poster paper focuses on Space Optics technology to provide a sample of the DSTL content. Using Distributed Sensor Network Architecture to Link Heterogeneous Astronomical Assets R.R. White, S.M. Evans, J.M. Pergande, W.T. Vestrand, P.Wozniak, J.Wren Los Alamos National Labs The internet has brought about great change in the astronomical community, but this interconnectivity is just starting to be exploited for use in this type of instrumentation. Here we present the Telescope ALert Operations Network System (TALONS), a network software suite that allows intercommunication between external and internal astronomical resources and controls the distribution of information to each of the resources. TALONS is an fundamental element of the Thinking Telescopes System, in operation at Los Alamos National Laboratory, and has been enabling great science for the past four years. The system allows a distributed network of telescopes to perform more efficiently in synchronous operation than as individual instruments. TALONS is designed as a merger between a standard server/client architecture and a Distributed Sensor Network (DSN). It can dynamically regulate its client base, allowing any number of heterogeneous resources to be linked together and communicate. TALONS couples that capability with collaborative analysis and maintenance modules so that it can respond quickly to external requests and changing network environments. TALONS clients connect via an intelligent agent, which acts in proxy for the scientist, allowing the telescope to analyze incoming information and respond autonomously. TALONS has a proven track record of effectively supporting the instruments at Los Alamos and other astronomical resources around the world. POSTER PRESENTATIONS Page 71 2006 AMOS Conference ABSTRACTS OF TECHNICAL PAPERS Structural Analysis of the 0.4 Meter Lightweight CFRP OTA at the NRL Christopher C. Wilcox1, Jonathan R. Andrews1, Sergio R. Restaino1, Ty Martinez1, Freddie Santiago2, Scott W. Teare3, Robert Romeo4, Don M. Payne5 Naval Research Laboratory, Remote Sensing Division, 2University of Puerto Rico – Mayagüez, Department of Physics, 3New Mexico Institute of Mining and Technology, EE Department, 4Composite Mirror Applications, 5Narrascape 1
A 0.4 meter Carbon‐Fiber Reinforced Polymer (CFRP) Optical Telescope Assembly (OTA) has been developed as a prototype by the Naval Research Laboratory (NRL) and Composite Mirror Applications (CMA). All components of this OTA have been made from the CFRP material, including the optics, and this has dramatically reduced the weight of the overall structure. The only components of this OTA that are not CFRP are the metal fittings, screws and the silvered mirror surfaces. The use of this material increases the portability of this OTA and can reduce the cost of future telescopes. However, because this material is more lightweight than the materials traditionally used in OTA construction, the vibration characteristics are different and obtaining optical surface quality is non‐trivial. This paper investigates certain structural properties of this OTA through the use of accelerometers attached and measurements taken statically and dynamically. Some measurements include the movement of the telescope at different speeds indoors and outdoors, as well as on and off a traditional tripod. Also, an impulse response measurement is obtained by tapping a weight to the OTA structure and the damping time is measured through the oscillations measured by the accelerometers. This OTA prototype is being developed for two future projects. The first being the development a 1.4 meter CFRP OTA for the upgrade of the Naval Prototype Optical Interferometer and the second being a lightweight deployable 0.4 meter CFRP OTA with adaptive optics. Furthermore, the properties of this CFRP material not only reduce the weight of the OTA, but the coefficient of thermal expansion is controlled such that this approach is very attractive for space‐based telescopes which, because of the light weight, can be deployed into space at a dramatically lower cost than traditional telescopes. POSTER PRESENTATIONS Page 72