Where No Dinosaur Has Gone Before:

Where No Dinosaur Has Gone Before:
Surviving an Asteroid Threat
Henry Ngo
Queen's University
14 April 2012
Asteroids are leftover planet bits
Asteroids are space rocks
951 Gaspra
(1992)
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Carbon or metallic
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Loose rubble piles
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Small solid rocks
Wikipedia
~ 12 km
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Very old!
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Range in sizes
4 Vesta
(2011)
~ 500 km
Wikipedia
Near-Earth asteroids
~ 1 - 25 m asteroid impacts
●
~ 1 / year
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Meteor
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Tiny meteorites
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Minor property damage
Grimbsy, ON Sept 2009 event
Credit: McMaster University
Peekskill, NY 1992 meteor
Popular Mechanics
~ 50 m asteroid impacts
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●
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Tunguska, Russia 1908 event.
http://apod.nasa.gov/apod/ap071114.html
~ 1 / 1000s years
Flatten forests in
30 km area
Feel heat at ~ 60
km away
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City-wide damage
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Tsunami risk
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LOW RISK
●
(1 in 500,000)
~ 100 - 500 m asteroid impacts
●
~ 1 / 10,000s yrs
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Regional damage
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Large craters
●
~ few km
Meteor Crater in Arizona (1.2 km)
(Source: Wikipedia)
Brent Crater, Ottawa Valley (3.8 km)
(Photo by Lachlan Cranswick)
~ 1 - 20 km asteroid impacts
●
~ 1 / millions of years
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Worldwide damage – debris in atmosphere
●
Personal risk: 1 in 40,000 chance
rawr? =(
Where no dinosaur has gone before
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Be prepared! Find dangerous asteroids!
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841 out of 1000 found today
“Copernicus Rex”
http://30characters.wordpress.com/
Finding asteroids
NEOSSat
Catalina Sky Survey
U. Arizona
MSCI Inc
2012 Launch date!
Finding asteroids
Asteroid 1982 TH (aka 2874 “Jim Young”)
Calculating orbits
+
=
NASA JPL Small Body Database
http://ssd.jpl.nasa.gov/
Asteroid impact risk
●
~ 8000 Near Earth asteroids known
●
~ 400 objects tracked by NASA
http://neo.jpl.nasa.gov/risk/
Torino Scale
Close encounters
Future observations likely to reassign to 0
Contingency plans if < 10 years away
> 1% chance of impact
Make contingency plans if ...
< 10 years away (local)
< 30 years away (regional)
< 100 years away (international)
> 99% chance of impact
Severe local, regional or global damage
Make plans immediately!
398 / 400 objects
2 / 400 objects (2011 AG5, 2007 VK184)
2 objects in the past, currently at 0
Highest historical rating
99942 Apophis (currently at 0)
Risk levels go up and down
Earth
Low risk object
Risk levels go up and down
Earth
Moderate risk object
Risk levels go up and down
Earth
Risk reduced to zero
Asteroid deflection
Zach Weiner
SMBC
Blow it up!
http://nanopatentsandinnovations.blogspot.ca
Hit it with a space probe
Don Quijote Mission (ESA)
2013 - 2015
Two spacecraft:
Hidalgo (impactor), Sancho (observer)
Hayabusa (Japan)
Mission to 25143 Itokawa
(size: few hundred metres)
Successful sample return mission 2005-2010
Gravitational tugboat
Where no dinosaur has gone before
Extra slides
Chicxulub
(“chick-sehr-lube”)
Yucatan, Mexico
65 million years ago
10 km asteroid
170 km crater
Chicxulub simulated effects
Fireball
Earthquake
(10.3)
Ejecta
Airblast
Tsunami
Near Yucatan
(250 km)
At Kingston
(2800 km)
Arrive in 12 seconds
200 times brighter than Sun
Trees, clothes, grass on fire
Arrives in 50 seconds
Buildings collapse, ground cracks
None (below horizon)
Arrives in 9 minutes
“Building hit by a truck”
Arrives in 4 minutes
Thickness: 60 m ( 200 feet)
Arrives in 12 minutes
8000 km/hr winds (5000 mph)
Trees, steel bridges collapse
137 dB (~ jet engine)
Arrives in 2.2 hours
30 – 60 m waves (100 – 200 ft)
Arrives in 16 minutes
Thickness: 4cm
Arrives in 2.5 hours
300 km/hr winds (180 mph)
Trees, glass windows shattered
92 dB (train whistle)
Arrives in 25 hours
3 -6 m waves (10 – 20 ft)
http://www.purdue.edu/impactearth/