Oct - Old WWW Site - Minnesota Astronomical Society

Minnesota Astronomical Society
a publication of the Minnesota Astronomical Society
In the pages of
the Gemini
Northern Nights Star Fest 2014
By Dave Falkner…Page 4
Lumicon Optical Filter
Discounts…Page 5
MAS Patron Members…Page 6
Dew…or Dew Not.There Is No Try
By Wayne Boline…Page 6
Modified Denver Observing Chair
By Steve Emert…Page 8
Directions to Star Party
Locations…Page 10
The Best Telescope at NNSF
By Star Fred…Page 10
MAS 2014 Star Party
Schedule…Page 11
MAS Board Minutes for July and August
By Roxanne Kuerschner, secretary…Page 11
October 2014
Volume 39 Number 5
Northern Nights Star Fest 2014
By Ken Hugill
Well, as much as I had hoped for clear skies this year, we had another year
of mostly cloudy weather. Just like last year, we started the Star Fest with a
fabulous Wednesday night of observing and then four nights of clouds and
sucker holes set in. We had a record crowd sign up again this year, forty-eight
in all. The Green Bay observers really made a showing; we had fifteen guests
from Green Bay. Maybe next year we will have better skies for them to enjoy.
Despite the bad weath er, I heard nothing but compliments on the Star Party
as a whole. I think the camaraderie, good food and great speakers helped us
forget about the clouds overhead.
For the first night of observing we had good skies all night long. Although
the dew was very heavy, most everyone stayed on task until astro twilight.
The dew was so heavy that water was beading up on things. The sounds of
grumbling and hairdryers could be heard by the time the midnight snack
rolled around. The temperature had dropped to the low fifties; needless to say
there were no mosquitoes.
As we went into the building for the midnight snack and turned down the
hall toward the dining room, John noted that there were trebles all over the
place. Yes, the furry creature from Star Trek, the treble, they were everywhere.
There were furry clumps illuminated by red LED lights. What the heck was
going on? Upon closer inspection they turned out to be large clumps of grass
that had been dragged in on the shoes of everyone in front of us. Because of
the lawn just being mowed and the heavy dew, large clumps of grass were
being deposited all the way down the hallway.
This year we ended up with quite a spread for the midnight snack. We had
hotdogs, chips, fruit, vegetables, cookies, cold cuts, bread and jellies. Hot dogs
can get a little tiresome after a few nights, so the additions were welcome.
Here are a few comments off the message board about the first night’s
observing:
Stories Wanted: Gemini is written entirely by our members, for our members!
Gemini needs your stories… how you
first became interested in astronomy, how
your interest has evolved over the years,
equipment you use, star parties and events
you’ve attended here and elsewhere, how
you’ve encouraged others — especially
young people — to get involved in this
fascinating hobby. Submit your stories to:
[email protected]
E-mail Update: If your e-mail address
has recently changed, chances are your address used for MAS email distribution lists
is not current. Please inform Bob Brose of
your new e-mail address at bob@qbjnet.
com
Brandon Hamil gave an interesting presentation about he incorporates
astronomy into his business travels.
• T
his was an awesome night at LLCC. Temps were mild, in the 60s. No
mosquitoes because I think the LLCC committee sprayed the area beforehand.
Thank You! Seeing and transparency were very good. Dew was quite heavy.
• We had an incredible display of Northern Lights around midnight to 1:00 a.m.
Thin and very bright vertical streamers came up from the north and west. One
especially bright started almost due west, went clear overhead, intersected the
Milky Way, and went well past the zenith and halfway to the eastern horizon.
• Some thin clouds rolled through at around 2:00 a.m., but they didn’t last.
• Personally, I logged 14 globs for the AL globular cluster list and two objects
on my never-ending quest to do the Herschel II list.
• Perhaps someone will post a few photos of the Aurora Borealis.
• Well, after one night of fabulous skies we are on our second night of rain. The
photons from Wednesday still have us energized and ready for clear skies on
Saturday night. Jerry, the cloud whisperer, is working hard to bring up clear
skies.
• If you haven’t been to NNSF, you’re missing a great astronomy experience:
Super-dark skies, great facilities, wonderful companionship, relaxing and
beautiful environment. I’ve been to every NNSF and will be there again next
year, with as many kinks worked out of my 20'' scope as possible.
The astronomy swap meet is always a popular event at NNSF.
This year we had some great lectures. We had two guest speakers from the
University of Minnesota. Once again I have to thank John for setting this up for
us. Brandon Hamil kicked things off on Thursday afternoon with “Traveling
Astronomer.” Brandon travels a lot for his job and has found a way to incorporate
his love for astronomy into each trip. Brandon seeks out observatories, vendors and
museums with an astronomy theme.
Professor Roberta Humphreys told how photographic plates from the Palomar Sky Survey were
digitized.
The solar observing scheduled for the afternoon was clouded out, so Star Fred
GEMINI • www.mnastro.org
2
GEMINI INFO
Editors
Brian Litecky and Eugene Brown
Webmaster
MAS Web Committee,
chair Merle Hiltner,
[email protected]
Forums Administrator
Russ Durkee
E-mail List Administrator
Bob Brose
Monthly Meeting Presenter
Coordinator
Lauren Nelson
Gemini is published 6 times annually
by the Minnesota Astronomical Society.
Electronic submissions for
Gemini may be sent to:
[email protected]
[email protected]
Hardcopy items should be sent to:
Minnesota Astronomical Society
Attn: Gemini
P.O. Box 14931
Minneapolis, MN 55414
Send MAS membership dues, changes of address and S&T subscriptions
to the MAS Membership Coordinator. Astronomy magazine subscriptions are available by contacting the
MAS Treasurer.
MAS Board Members
President: David Falkner
E-Mail: [email protected]
Phone: 763-785-0539
Vice President: Steve Baranski
E-Mail: [email protected]
Phone: 763-792-9262
Treasurer: Chris Hansen
E-Mail: [email protected]
Phone: 612-701-2785
Secretary: Roxanne Kuerschner
E-Mail: rkuerschner@waconia
K12.mn.us
Phone: 320-864-5798
Board Member: Greg Haubrich
E-Mail: [email protected]
Phone: 763-421-4736
Board-Member: Wayne Boline
E-Mail: [email protected]
Phone: 763-533-3229
Student representative:
Josh Torgeson
E-mail: [email protected]
Phone: 952-442-3924
showed us some astrophotography and the software he wrote to
process the images. All the astrophotographers were sitting on
the edge of their seats drooling over the custom capabilities for
image processing that Fred put into his software. I was lacking
a speaker for Thursday night, so luckily Joe Timmerman was
able to talk about his experience building a home observatory,
which he called Pebble Hill. The pebble in this case is a huge
rock that he struck when digging the footings.
a lecture on basic astrophotography. It was a good thing the
“show us your ATM” on the field was rained out, since my
lecture took us until dinnertime. On Friday night we had a few
sucker holes come through about midnight. Jerry got out his
newly rebuilt Astroscan and started observing. There was a
small crowd standing around the 4” scope grabbing impressive
views of objects as the sucker holes passed.
Dick Jacobson started out Saturday’s lectures with his
flatscope. Dick comes up with some of the most interesting
inventions, and each year it is great to see what he has built.
The flatscope was featured in a past Gemini article [June 2014];
if you have not seen it or read the article yet, you should look it
up.
On Saturday afternoon Steve Baranski and Star Fred
lead a group on image processing. I spent the time prepping
the 25'' and 30'' for what we thought would be another night
of observing. Saturday night’s speaker was Professor Kris
Davidson from the Minnesota Institute of Astrophysics. Kris
talked about his favorite subjects, Eta Carina and supernova
imposters.
The observing list this year was called Double Trouble;
it contained double stars and a handful of objects that may
give you trouble and challenge the aperture of your scope.
Unfortunately the poor skies prevented people from completing
the list. Dave Falkner was the only one who was able to find
25 objects on the list to qualify for a certificate. I bring copies
of each year’s list, so maybe next year people can catch up on
obtaining their NNSF certificates.
The swap fest was a success again. For those of us who
sold or purchased items, it was well worth it. I would like to see
everyone bring something to sell, but a lot of people stated that
they either forgot or did not have time to get things ready. Next
year I will try to send reminder e-mails to people signed up to
bring stuff to sell and barter. I was able to sell about 50% of the
items I brought. I picked up some LED desk lamps and added
red jell to them to make a nice map light. I think in the future I
will add a dimmer so I can adjust the brightness, although this
will raise the cost from $4 to $6.
Professor Kris Davidson spoke about Eta Carina and
supernova imposters.
The featured speaker on Thursday night was Professor
Roberta Humphreys, from the Institute of Astrophysics. She
talked about the history of the Control Data plate reader.
Ken Hugill gives training on the 25” and 30” Dobs.
The solar observing I had scheduled was clouded out.
The ATM tour of the field was rained out. I was able to do key
holder training on Friday night, but it then clouded up and we
were not able to practice a two star alignment.
Here are some of the comments on the evaluation forms:
I enjoyed the Minnesota hospitality. It was a great star
party! Thanks for inviting us and having a great facility. We met
Dick Jacobson, MAS inventor, gave a demonstration of his flatscope.
Dave Falkner kicked off Friday’s lectures with “The
Journeys of Spirit and Opportunity.” Then I followed up with
3
August 2014
An aerial view of the observing field at NNSF, taken by Mark Connolly’s drone.
many great people and plan to come back again. Thanks!
I enjoyed the fun group of people and the dark skies. It’s a
great facility. We need more time looking through the 25” and
30” scopes.
Let’s have bacon next year for brunch.
We missed Bob Kerr and his fabulous lectures.
I enjoyed speaking with people of like interest. I enjoyed
Kris’s talk on super nova imposters.
A more open observing field with better horizons would be
nice, but I know it’s not realistic.
I enjoyed the one clear night and th e speakers.
Good venue, good food, good speakers.
Need some speakers on cosmology and space news.
I enjoyed the quiet of the rooms and the friendliness of the
leaders.
I enjoyed the camaraderie.
Thank you to all who attended NNSF this year, and I hope
to see you at NNSF next year.
Northern Nights Star Fest 2014
observation enthusiasts. Some of the more interesting objects
seen were Neptune with its largest moon, Triton; the no-longera-planet Pluto; and a number of deep-sky objects. In addition,
around 11:30 we were treated to a spectacular aurora with green
spires jutting above the trees.
After the midnight snack we returned to the field and were
witness to an unusual aurora event. A shaft of light originated at
the western horizon and extended to the east through the zenith,
crossing the Milky Way and ending at Aries in the eastern
sky. It varied in brightness and its structure shifted, but the
phenomenon remained visible for over 30 minutes. No one in
By Dave Falkner
The sixth annual Northern Nights Star Fest was held
August 27-30 at Long Lake Conservation Center. We had a
record number of registrants, requiring the use of both the
North Star Lodge and the Marcum House to accommodate all
the folks who came.
Wednesday night brought clear skies and excellent seeing.
The transparency varied a little but overall was very good. The
field was full of telescopes with a number of imagers but mostly
A view of the magnificent
Northern Lights shortly before midnight at NNSF.
GEMINI • www.mnastro.org
4
Mark Connolly took this photo of the night sky at
NNSF. The arrow indicates the position of the Andromeda
Galaxy.
able to visit over the last several years in conjunction with his
business travels. He has been fortunate to meet many of the
prominent names in amateur astronomy, both in observational
astronomy and in the equipment that amateurs use.
On Friday afternoon I spoke about the Mars Exploration
Rovers, Spirit and Opportunity, and the research they have
done while on Mars over the last 10 years. The talk was well
received. On Friday evening Roberta Humphreys from the
University of Minnesota talked about the Palomar Sky Survey,
which was recorded on photographic plates, and how, with the
help of Control Data Corporation, a special plate scanner was
created to scan the plates and digitize the data.
attendance had ever seen an aurora like that. References online
called such an event an aurora shaft or aurora beam; it is a fairly
rare occurrence.
I worked on the NNSF observation list, which included a
number of double stars and deep-sky objects, some of which
were familiar—such as the Dumbbell Nebula (M27), globular
cluster M15 in Pegasus, and the Wild Duck Cluster (M11). I
was able to complete the minimum 25 observations before my
brain shut down around 2:00 a.m. I wandered back to the North
Star Lodge and to my bed. Later reports indicated that the skies
were good until around 4:00 a.m., when the clouds rolled in.
Thursday, Friday and Saturday were accompanied by
overcast skies and occasional rain. However, the weather failed
to dampen the spirits of those who were attending.
Dave with his 12.5” Dob.
On Saturday evening Kris Davidson from the University
of Minnesota talked about super-massive stars which detonate,
but not explode, and release huge amounts of stellar material
but continue to exist. These stars are fairly rare, and the process
of releasing huge amounts of matter without exploding is not
understood.
As usual the food at NNSF was fantastic, with plenty
available at each meal. We had the usual variety with no two
meals alike. The midnight snacks were particularly great, with
hot dogs, cold cuts, cheese, chips and leftover desserts.
On Saturday night the whole group pulled their chairs into a
large circle to swap stories. After the midnight snack—at 11:00
p.m.—the group agreed that we’d had enough and we began to
pack up our telescopes.
Despite having only one good night, the weekend was a
success. It was the largest attendance at NNSF so far, and the
people were delightful and friendly. I’m looking forward to next
year.
A photo of an unusual streamer in the Northern Lights. Most of the
guests at NNSF had never witnessed such an event.
The speakers were excellent, as usual. On Thursday,
Brandon Hamil gave a great presentation, talking about all the
retail stores, observatories and astronomy clubs he has been
Lumicon Optical Filter Discounts
If you have questions, you can contact Lumicon directly: Sam
Sweis, Lumicon: Phone 805-520-0047. Cell: 805-813-3135;
[email protected]; www.lumicon.com; www.
parksoptical.com Lumicon offers a $25 discount order code to all MAS
members for orders of greater than $99.99 for Lumicon filters
or Parks Optical telescopes and accessories. Simply visit www.
lumicon.com and use discount code MNAS25 on your order.
5
August 2014
MAS Patron Members
Patron memberships are available to those who wish to contribute a little extra to support MAS activities. Patron memberships
are established by constitution at 2-1/2 times the Regular membership rate—currently $65 annually for a patron membership.
The $39 additional contribution is tax deductible. Patron memberships help fund equipment acquisitions, facility improvements,
outreach activities and more. We would like to thank the following patron members as of August 24, 2014.
Hytham Abu-Safieh
Ted DeMatties
Michael P. Haydock
Louis M. Leichter
Loren Schoenzeit
Scott D. Anderson
Mary L. Dennis
Jonathan Hayman
Clayton Lindsey
David A. Schultz
William Arden
Courtney Dietzmann
Victor H. Heiner
Brad Linzie
Robert J. Seabold
Jack W. Atkins
Brogan Duffy
Ric Heins
Walid Maalouli
Dan Siers, Sr.
Steve Baranski
Russell I. Durkee
John E. Hill
Tim Maher
David E. Siskind
Greg Baril
John G. Dwyer
Lauren Hoen
Brian McEnaney
Cindy and Al Smith
William Beauchemin
Jim Elmquist
Michael Hopfenspirger Ron McLaughlin
Drew Smith
Bradley Beisel
Steven W. Emert
George Hulme
Javier Medrano
Thomas R. Smith
Mike Belzer
Alan Fackler
H. Richard Jacobson
Rebecca & Gary
Gerald S. Smyser
David Bendickson
Dennis Faith
Gale Jallen
Messer
Geoffrey Stone
Scott Billeadeau
David Falkner
Mark Job
Bob Minor
Gathroe Taylor
Ken Bolvin
Joe Fisher
Chelen H. Johnson
Brian Nelson
Valts Treibergs
Brandon Borrillo
Robert Foucault
Julie A. Y. Johnson
Alan Noot
David Truchot
Rev. Eugene M. Brown Andrew D. Fraser
Jerry Jones
Douglas J. Oines
Carl Tubbs
Jonathan Burkhardt
Paul Gade
Daniel G. Kaminski
Ken W. Pederson
Steve Ulrich
Jeff Burrows
William H. Glass
Ron Kasel
H. Doug Plunkett
Max Van Riper
William Bynum
Steve Grabarkiewicz
Michael T. Kauper
Becky Pollack
Bob Vangen
Ken Carlson
Lawrence F. Gray
Jim Knudsen
Brian Rembish
David E. Venne
Kurt A. Casby
Matt Gross
David Kocken
Kirby Richter
Paul C. Walker
Deane R. Clark, Jr.
Jere N. Gwin-Lenth
Timothy Kraemer
Stephen Riendl
Fred Wall
Mark Connolly
Dale Hagert
Parke W. Kunkle
Jack Sandberg
Brian Wray
John M. Cooner
Brandon Hamil
Pete Lacey
Roy Cameron Sarver
Gene Yates
Mike Daniels
Greg Haubrich
Jonathan Larson
Dean M. Schantzen
Neal R. Zimmerman
Mary Beth Smith &
Thomas E. Hawkinson
Christine Laughlin
James L. Schenz
Dew…or Dew Not.There Is No Try
(with apologies to Yoda and friends)
of resistors, each resistor spaced ¾” to 1” apart, around the optical
tube, eyepiece, etc., close to the mirror or lens I want to protect.
Many other MAS members have built effective DIY antidew systems; this is just one option. I gathered information
from the MAS forums and other locations on the Web. The
commercial systems I looked at were $150 and up. Mine cost
less than half of that.
Judge me by my size, do you? Such a small thing to hold
all of that water at bay! The finished dew straps are 5/8” to 1”
wide and long enough to fit around the item to be protected.
The amount of power that a small dew strap uses is comparable
to a flashlight. My entire setup of five dew straps uses 22 watts
(1.9 amps) with the controller set at maximum output. A crude
jig with clamps at both ends holds the speaker wires tight and
parallel. This makes it easy to splice the resistor leads around
the side rails and solder them together.
By Wayne Boline
You no longer see any galaxies. You notice a glow around
the brighter stars. Then… nothing. You can’t see anything
through the eyepiece. You look up; it isn’t clouds. You have dew
(or frost) on your optics. While you’ve been enjoying the night
sky your scope has been radiating heat, cooling it below the
dew point. The atmosphere is full of moisture just waiting to
condense on your scope.
You can pack up your kit and go home. Or you can turn up
the dew heater you just made.
You need heat, but not that much. The right amount of heat
applied to the right place is just enough to keep the moisture from
condensing on your optics. I accomplish that by wrapping a ladder
GEMINI • www.mnastro.org
6
The initial design is a resistor ladder surrounded by heat
shrink tubing (waterproof), sealed at the ends with duct tape,
covered by adhesive-backed soft-loop Velcro and secured with
a piece of hook Velcro. When turned on, the strap became
warm to the touch. But several hours later, especially on very
wet nights, it felt cold and I had dew on the optics. What was
wrong? The soft Velcro had turned into a sponge. The resistors
could not heat both the optics and the wet covering. Moisture
absorbed by the Velcro was removing heat from the dew strap
as fast as it was generated.
each other (I was surprised by how many other things in my
home generated much stronger radio frequency interference!).
I studied both commercial and DIY ideas on line and
decided on the following for the controller:
• Three PWM kits for three independently controlled channels
(from www.quickar.com)
• Three RCA jacks to feed power to the dew straps (Radio
Shack)
• 12-volt DC power jack (Ax-Man Surplus)
• Power switch (Ax-Man Surplus)
• 3-amp fuse (Radio Shack)
• Variable indicator light showing the level of power supplied
to the dew strap on each channel (small acrylic rod acting as
light guide from PWM’s LED to exterior of enclosure)
• Enclosure (5” x 2.5” x 2” from Radio Shack)
• 2 RCA splitters to allow three channels to power five dew straps
Covering the Velcro with duct tape created many small
insulating air pockets protected by a waterproof barrier.
Problem solved. The first night at this year’s Northern Nights
Star Fest brought dew even before it was dark, yet my mirror
and finder scope stayed clear throughout the night. The few
resistors in my eyepiece strap delayed but did not prevent dew
on my biggest eyepiece. However, rotating eyepieces through
my heated eyepiece tray took care of that problem (See my
article in Gemini, August 2012).
Dew strap cross section.
These are the dew strap parts:
• Speaker wire (Radio Shack, chosen for flexibility and
durability)
• 330-ohm resistors (Radio Shack)
• RCA jacks (Radio Shack)
• Velcro (Joanne’s Fabrics)
• 1” and ¾” wide heat shrink tubing (AEI Electronics)
The commercial anti-dew products use pulse width
modulation (PWM) to control the amount of current delivered.
Why PWM? Power loss is very low; you are not wasting
electricity by turning it into heat in the controller. PWM
operates by supplying the full 12 volts but turning on and off
very rapidly. The Quickar Electronics PWM kits have an on/off
frequency of 150 Hz, which works great with heating circuits.
By its nature PWM generates radio waves, but I have not
observed any interference with other equipment (guide camera,
DSLR, etc.), even though the controller is less than 18” away.
An AM radio tuned off-channel did pick up static from the
control box, but only when they were less than six inches from
7
Original working plan.
August 2014
Resistance in the circuit generates heat, but how much
resistance do I need? To answer that question and others, I
used an Excel template (created by Al Sheehan, IceinSpace.
com) to figure out what I needed for each of my five dew heater
straps. Enter the data in the green cells and it recommends the
number of resistors and their spacing and provides details on
power consumption, etc. (http://www.iceinspace.com.au/index.
php?id=63,292,0,0,1,0)
Al’s resistor dew heater.
That’s it! Build it and you won’t have to worry about the dew.
Modified Denver Observing Chair
durable. Also, being that it’s made out of a 2x4 and exteriorgrade plywood, you won’t be inclined to make it a visual
masterpiece, so you won’t mind when it inevitably gets dirty
and nicked up during use.
by Steve Emert
No, I’m not talking about Jerry Jones’ counterpart in
Colorado, but rather something to sit on! Most everyone has
heard of the Denver Observing Chair. For those who have not,
it is a chair, very simple and inexpensive to build, that greatly
enhances your observing experience. The original plans can be
found here: http://www.denverastrosociety.org/dfiles/carlson/
denver_chair.html
Folded chair showing bottom angles.
A few years ago I built a Denver chair and mostly adhered
to the plans as provided. Two drawbacks I found were that the
wide crosspiece at the front of the chair interfered with getting
close to my Dob for good positioning, and the split heater
hose fastened to the back edge of the seat, which provides the
friction grip to keep the seat from sliding down, simply doesn’t
have enough surface area to provide a good grip. It also wears
out quickly. I modified it by changing the grip surface to a flat
rubber gasket cemented to a 2x4 vertically mounted at the back
of the seat. I used it that way for a while until I gave it away
after I was given a gift certificate for Astronomics and bought
a Starbound chair. I used the Starbound chair until one winter
evening, when I found that this chair had a tendency to slip as
well. The friction support for the Starbound chair is a semi-hard
plastic tube against the steel tube structure of the chair. The
hose became stiff and lost its grip in the cold. I slipped down,
my feet flew out and caught the cables for my altitude encoder,
and I ripped the connector off the encoder. I was able to fix it,
but that was enough of that chair! It’s now in the Cherry Grove
Observatory for members to use—but if you use it when it’s
cold out, remember—you have been warned!
In building this chair, the modifications I made were:
The use of the flat orange rubber gasket on the back edge
of the seat support as the friction grip, against the tread tape on
the front support member. This works very well, giving a lot of
surface area to grip the chair support. It also allows you unlimited
adjustment along the length of the front support by just lifting
the seat up a little and sliding it up or down. One thing I found
is that I could no longer attach the gasket material to the wood
using contact cement. New “environmentally friendly” low VOC
Front view of observing chair.
If you perform a Web search you will find several additional
articles with various versions that others have made over the
years. This article covers the modifications I decided to make
when building a few of these chairs several weeks ago.
This is a nice, quick, one-day project if you decide to
build it without painting or polyurethane sealing, or a weekend
project if you to seal your chair against the elements. There
are certainly nicer commercial observing chairs around, and
many much nicer-looking home-built chairs. (If you are at a star
party with Dave or Bill Kocken, check out their beautiful oak
observing chairs based on the Catsperch chairs.) In addition to
wooden chairs, there are also commercial metal chairs such as
the Starbound Observer’s Chair.
Why use an observing chair, and why specifically would
you want to use a cheap-looking thing like the Denver chair?
An observing chair truly helps you see celestial objects better.
When you are sitting you are not trying to balance yourself,
and depending upon the eyepiece height you are not bending
over at odd angles. That lets you relax and keep your eye more
stationary over the eyepiece, increasing the detail you can
see; you can also view objects to deeper magnitudes than you
could otherwise. And the homemade Denver chair is cheap and
GEMINI • www.mnastro.org
8
(volatile organic compound) contact cement has poor adhesive
qualities as compared to older contact cement. After trying that
and seeing it fail, I took as much of the contact cement off as I
could and then used silicone glue (silicone sealant, 100% silicone
caulk, RTV) to re-glue the gasket material. The gasket material is
available at Ace Hardware.
crosspieces to the uprights with wood glue and with plenty of
long construction screws (drywall screws). I had noted in my
old chair, which had just two large lag bolts, the tendency for
the crosspieces to work loose from the torque of leaning side to
side while using the chair.
Rubber gasket seat friction material and seat spacer 2x6.
Chair folded for storage.
Angled bottoms for the bottom crosspiece chair supports.
If you have a table saw so you can rip wood lengthwise,
I recommend cutting the bottoms of the crosspieces at an
approximately 30-degree angle and cutting the bottom edge
of the uprights at the same angle. This provides a flat surface
parallel to the ground, especially helpful if you are observing
from a driveway or cement pad.
Make sure to mount the aluminum horizontal cross-brace
just below the top of the 2x4 chair support cross-brace 2x4s, so
the seat can slip down all the way to the top of the horizontal
cross-brace during use and especially during storage.
The use of a cut-down 2x6 for the seat-support spacers. In
the original article, the author says to use a couple of cardboard
spacers to make the 2x4 seat spacers wider to provide the gap
so the seat can be slid up or down. I had some scrap 2x6s, so
instead I just cut it about 3/16” wider than the 2x4 width.
Increased upright height. The original article says to make
32” uprights. I increased my uprights to 42” to give me a little
more height adjustment for viewing near zenith. It also gives
some additional back support I wouldn’t have otherwise had.
This modification is a personal preference, and of course it has
the drawback of making the chair a bit larger and heavier.
Velcro holding cross brace.
Copious use of Velcro. I have a Velcro strip glued to the rear
upright and to the inside edge of the aluminum horizontal spacer/
brace to hold it in place during storage and transport. I also used
a long piece of the “wrap to itself ” Velcro with the hooks on one
side and loops on the other side in order to hold the seat tightly
closed against the front upright during transport and storage.
I highly recommend building an observing chair—or build
a couple and give one to a friend! A 2x4-foot 3/4” plywood
handy panel has enough plywood to make three seats. Once you
are set up it doesn’t take much longer to build three of them
than it does to build a single one.
Chair ready for use.
Chair supports. I have a short 12” crosspiece attached to
the front upright and a longer 24” crosspiece attached to the
rear upright. This keeps the crosspiece from interfering with
positioning near the scope; also, the use of two crosspieces
keeps the chair from sinking in to soft ground in the spring.
It also provides support for the chair to be stored upright
in my garage with no chance of tipping over. I fastened the
9
August 2014
Directions to the Star Party Locations
For maps and further details about the sites, please go to our website at www.mnastro.org/facilities.
Baylor Regional Park and Eagle Lake Observatory
To reach Baylor Regional Park, head west on Minnesota Highway 5, through Chanhassen and Waconia, to the town of Norwood-Young America. Turn right onto Carver County Road 33 and continue approximately two miles north. Baylor Regional Park is on the right side of the road,
marked with a prominent sign. When entering the park, stay to the right and follow the road approx 1/4 mile.
When visiting the Baylor Regional Park, MAS members are requested NOT TO PARK OR DRIVE on the grass. There is a drive up to the observatory which can be used for loading or unloading or handicapped parking only.
For an alternate route from the southern suburbs, take U.S. Highway 212 west to Norwood-Young America. Turn right at the second traffic light
onto Carver County Road 33. Continue two miles north to the park entrance.
Cherry Grove
Cherry Grove is located south of the Twin Cities,in Goodhue County, about 20 miles south of Cannon Falls. To reach Cherry Grove, head south
on Highway 52. On 52 about six miles south of Cannon Falls, and just past the Edgewood Inn, is a large green highway sign for Goodhue
County Rd. 1 “WEST”. Turn right, and follow County 1 straight south for about sixteen miles until you arrive at a “T” intersection with County
A. The observatory is immediately at your right, nestled in the shoulder of the “T”. Parking is permitted on the site, or along the road, preferably
County A.
Metcalf
Head east from St. Paul along Hwy. 94. Exit at Manning Avenue ( exit #253) Turn south (right turn) and then almost immediately turn left onto
the frontage road (Hudson Road S). Continue east on the frontage road for about 1.5 miles. Turn right onto Indian Trail, checking the odometer
as you turn. Follow Indian Trail south for just about 1.1 miles, where you’ll see an unmarked chain-link gate on the right, opening onto a dirt
driveway with slight up-slope. This is the entrance to Metcalf.
Belwin / Joseph J Casby Observatory
Head east from St. Paul along Hwy. 94. Exit at Manning Avenue ( exit #253). Turn south (right turn) and then almost immediately turn left
onto the frontage road (Hudson Road S). Continue east on the frontage road about 3.4 miles until Stagecoach Trail South, then turn right onto
Stagecoach Trail and go east about 2 miles until reaching Belwin Conservancy on your left at 1553 Stagecoach Trail South. From the Belwin
driveway entrance, y travel about 500 feet and turn left at the gate. Travel about 1/4 mile through the woods until you emerge at the parking area
near the classroom building and the Joseph Casby Observatory.
Long Lake Conservation Center
From Western Twin cities
Take I-94 west to Rogers/MN 101. Go north/right on MN 101 through Elk River, where MN 101 becomes USA 169. Continue north on US 169
approximately 90 miles to Aitkin. At stoplight in Aitkin, turn east/right onto US 169/MN 210 and go out of town eight miles. Then turn east/
right, following MN 210 toward Duluth. Proceed seven miles. A large green highway sign marks the turn off 210 to Long Lake Conservation
Center. Turn north/left on County Rd. 5. After three miles, turn east/right on gravel County Rd. 88. It is approximately one mile to the LLCC
gate. Follow signs to parking and unloading areas.
From Eastern Twin cities
Go north on I-35 to Finlayson/Exit 195. Turn west/left and go one mile to County Rd. 61 and MN 18. At stop sign turn right/north and go two
miles. Follow MN 18 west/left and continue 19 miles to MN 65. Turn north/right on MN 65 and proceed 30 miles to McGregor. Intersect with
MN 210 and follow 210 west/left (through McGregor) for seven miles. A large green highway sign marks the turn off MN 210 to Long Lake
Conservation Center. Turn north/right on County Rd. 5. After three miles, turn east/right on gravel County Rd. 88. It is approximately one mile
to the LLCC gate. Follow signs to parking and unloading areas.
The Best Telescope at NNSF
By Star Fred.
After carefully scrutinizing the satellite imagery, six of us
hit the viewing field shortly before 1:00 a.m. on Friday. Much
to our delight, the haze was clearing rapidly. Jerry Jones soon
cracked out his 3.5” Astroscan and we immediately began to
examine the night sky. Our first target was the beautiful, colored
double Alberio, followed closely by M57, the Ring Nebula.
The donut shape of the ring was readily apparent, but alas, the
central white dwarf eluded us.
After we recovered from our short bout of laughter, we
moved on to the nearby globular cluster M56. With an eyepiece
change to afford a wider field of view, we enjoyed a view of
the Coathanger asterism. Since we were already in wide-field
mode, we slid over to the Great Andromeda Galaxy, M31, and
then the Double Cluster in Perseus, NGC884 & NGC869.
Off in the distance we could hear the distinct sound of truss
tubes being clamped together as some overzealous astronomer
began to assemble his 20” Dob. The particular demon (not a
god) who had been assigned to weather watch that evening also
heard the commotion and simply waved his hand to wash away
the clear sky we had been enjoying. Clouds prevailed for the
GEMINI • www.mnastro.org
remainder of the night and by daybreak it was raining again.
Since the best telescope is the one that you use, at least for
Friday night the little Astroscan was the best telescope on the
field.
The little 3.5” Astrocam. The users closed their eyes so they
would not lose their night vision from the flash.
10
Minnesota Astronomical Society 2014 Star Party Schedule
Friday
Totally dark
Totally’
Moon %
Onan Public
LLCC
Date
Sun-set:
Twilight from
dark to
Illuminated
Night (Sat.)
Cherry Grove Weekend
Oct 17
6:23p
6:52p
8:00p
2:16a
29%
Oct 18
X
*
6:13p
6:43p
7:51p
6:01a
0%
Thurs
Oct 23
6:11p
6:41p
7:50p
6:02a
2%
X
*
Oct 24
5:59p
6:30p
2:44a
6:11a
72%
Nov 01
4:42p
5:14p
6:25p
1:00a
37%
Nov 15
Notes
Partial Solar Eclipse; canceled if cloudy
This schedule is subject to change. Please check the MAS online calendar at www.mnastro.org for a complete schedule of all MAS events.
Cherry Grove star parties are held on Friday nights, with Saturday reserved as the backup night if Friday is cloudy. LLCC star parties are held
on both Friday and Saturday nights. Eagle Lake public nights are held on Saturday nights only.
The Casby Observatory at Belwin is available to MAS members who have completed the Belwin orientation and training to use at any
time. We do not have scheduled star parties at Casby. To reserve the observatory for yourself, please post your request on the Casby Observatory Keyholders discussion forum.
The Metcalf Observing Site is available to MAS members at any time. We do not have organized, scheduled star parties at Metcalf. Feel
free to head out there whenever you wish.
The Eagle Lake Observatory holds regularly scheduled pubic nights. You are welcome and encouraged to bring your own observing equipment to these events. All other nights the observatory is available for trained members’ use. To reserve the observatory, go to the Onan reservation calendar at http://www.mnastro.org.onankey/reservations/reserve.php Before heading out, please check the Onan reservation calendar to
verify that there is no outreach event scheduled. In 2014, daylight saving time begins March 9 and ends on November 2.
MAS Board Minutes for July and August
By Roxanne Kuerschner, secretary
July
Preparations for Lunar Rock Display: The sidewalks are
done at Eagle Lake Observatory and the piers are poured and
telescopes remounted. The display boards are done and a media
announcement has gone out, but so far no interest. There will
be a work party on Saturday to complete the setup. Camping
with the Stars: There will be fewer speakers due to the moon
rock exhibit in the classroom. There will be a drawing and door
prizes. Cherry Grove Observatory: The survey is complete to
see the property lines. The light fence construction has begun.
The smaller tripod from Onan might not work out as originally
planned; it will be determined by the site coordinator whether
to use the existing one. Observatory Passport Program: This
is tabled until September. Celestron Cosmos First Scopes:
They have been ordered by Wayne and will be ready for
Camping with the Stars as door prizes. 8” Loaner SCT: It
has been repaired and is back in the loaner program. Filters at
J.J. Casby: Jon Hayman wants to replace filters at J.J. Casby.
There shouldn’t be any issues with that. Keyholder Concerns:
There are concerns that keyholders are not holding up their
end of the bargain on helping with work parties, and there has
been damage to equipment by member usage. A tiered fee
schedule has been suggested for keyholders. It is agreed that
(at least at ELO) there needs to be adherence to the rules for
keyholders to assist at work parties. The site coordinator could
maintain a list of those who have assisted, and if the keyholder
has not been active for a year a probation as a keyholder could
be invoked. A clearing of keyholders is needed, since there are
some who have not been around for years (especially at ELO).
There should be a way to check who was using the facilities and
monitor the damage. Some ideas: an apprentice program for
new keyholders; having an experienced member shadow them
several times before they are able to check it out on their own;
have potential keyholders be members for six months before
they are eligible. Sale of Tripods: Tripods need to be sold if
GEMINI • www.mnastro.org
11
we are not going to use them. The donor will be contacted to
see what, if any, preference there is for their future. Hosting of
Regional ALCON: It has been suggested that MAS assist in
hosting a regional ALCON. A hotel with meeting rooms would
be needed; there would be events at ELO during the day and
evening. Dave will contact the person to see what is needed.
New Observing Spot: Dave contacted the person who had
a potential spot available for observing, the Shamrock Golf
Club in Corcoran. It might not be a very good spot due to light
pollution. Dave will go out there to see the conditions, sight
lines, etc. Display at the Library: The Brookdale Library has
display windows available if we would want to highlight MAS.
August
Sale of Tripods: Dave will take care of posting the
mounts on Astromart, as Cherry Grove does not need them.
Maintenance Update: Greg is working on the insurance list.
He will commit to finishing it by the next meeting. Hosting
ALCON: There is interest in having MAS host it in 2018. Dave
will follow up for more information. New Observing Spot: The
site is good, other than the amount of light pollution. It would
work for double stars or the Moon. Northern Nights Star Fest:
A speaker for Thursday is still needed. Western Boundary
Light Fence at Cherry Grove: The fence is up and it looks
very nice. Election Chairman: Wayne will take over the
chairman’s position. President, secretary and board-member-atlarge are up for election. Member of the Year Award: This is
the time to recognize the member who does a wonderful job for
the club who may not be recognized by the membership. There
are many possibilities. The names will be decided at the next
meeting. JJ Casby Committee Members for Board Approval:
Steve Ruples (for Metcalf), Clayton Lindsey, Mike Malik
and Mark Connolly were added to the JJ Casby Committee.
The board approved the list. Jon Hayman and Merle Hiltner
were approved to continue as members. Site Committee Term
Renewals: A notice should be sent out to the sites to make
sure that the names of those who are on the committee are
submitted.
MN ASTRONOMICAL SOCIETY
P.O. Box 14931
Minneapolis, MN 55414
a publication of the Minnesota Astronomical Society
How to pay your dues
ADDRESS SERVICE REQUESTED
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PAID
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PERMIT NO. 1407
October 2014 Volume 39 Number 5
Your MAS membership expires at the beginning of the month shown on your Gemini mailing label. Send your payment to the MAS
Membership Coordinator at: Minnesota Astronomical Society, Attn: Membership Coordinator, P.O. Box 14931, Minneapolis, MN 55414.
Make checks payable to MAS, or you can pay by PayPal on the MAS Web page. The current annual membership dues and subscription
fees are: $26 for regular membership, $13 for student membership, and $65 for patron membership. For a printed copy of Gemini, add $9
to the above memberships. For a subscription to Sky and Telescope, add $32.95. For a subscription to Astronomy magazine, add $34 for
one year or $60 for two years.
Membership rates changed as of February 1, 2014. The new rates are posted on the membership application form at http://www.
mnastro.org/membership/MembershipForm.pdf
Fees for each of the membership levels were reduced and the option of receiving a printed copy of Gemini and/or Astronomy magazine as well as a place for an additional tax-deductible donation was added.
To Renew Your Sky and Telescope Subscription
New subscriptions to Sky and Telescope at the MAS member discount must be sent to the MAS for group membership subscription
processing. Send new subscriptions with your MAS membership to the attention of the Membership Coordinator at the MAS at the Post
Office box address shown on the back cover of the Gemini newsletter.
You may mail your subsequent subscription renewal with payment directly to S&T or renew via phone with Sky Publishing at 1-800253-0245. This method is especially beneficial to those who wait until your subscription is about to expire before renewing S&T. If you
wish, you may still submit your S&T subscription renewal to the MAS when you renew your membership in the MAS and we will enter
your renewal on your behalf just as we always have done.
You will still need to send in your MAS membership renewal to the MAS Membership Coordinator at the MAS Post Office box address or renew your membership via PayPal.
How to Subscribe to MAS e-mail Distribution Lists
The MAS uses web Discussion Forums and e-mail distribution lists for timely communications. We highly recommend you subscribe
to the MAS general distribution email list.
To subscribe to the MAS e-mail list visit: http://lists.mnastro.org/mnastro/listinfo/ and follow the subscription instructions.
There is a general list (MAS), several Special Interest Group (SIG) lists and other lists for special purposes. Archives of the lists are also
available by visiting the listinfo page for a specific list.