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Asteroids, Black Swans, Asteroids, Black Swans, Global Catastrophic Risks, Global Catastrophic Risks,
and How to Save Civilizationand How to Save Civilization(cloudy night version)(cloudy night version)
JCCC Science CenterJCCC Science Center
Evening with the StarsEvening with the StarsSaturday 24 October 2009Saturday 24 October 2009
AgendaAgenda
AsteroidsAsteroids• Basics – What/Where/How ManyBasics – What/Where/How Many• Impacts You’ve Heard OfImpacts You’ve Heard Of• Craters You Can VisitCraters You Can Visit• Impacts You Impacts You Haven’tHaven’t Heard Of Heard Of
Black SwansBlack Swans Global Catastrophic RisksGlobal Catastrophic Risks
Agenda Agenda (cont’d)(cont’d)
How to Save CivilizationHow to Save Civilization• Think GloballyThink Globally• Act LocallyAct Locally• 2008 TC32008 TC3
Astronomical Society of Kansas CityAstronomical Society of Kansas City
What Are Asteroids?What Are Asteroids?• Small solar system bodies that Small solar system bodies that aren’taren’t comets or comets or
meteoroids.meteoroids.
• The formerly largest asteroid, 1 Ceres, is now The formerly largest asteroid, 1 Ceres, is now classified as a classified as a dwarf planetdwarf planet..
• Discovered 1 January 1801 by Giuseppi Piazzi Discovered 1 January 1801 by Giuseppi Piazzi in Palermo, Sicilyin Palermo, Sicily
IAU members gathered at the 2006 General Assembly agreed that a “planet” is defined as a celestial body that(a) is in orbit around the Sun(b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium
(nearly round) shape, and(c) has cleared the neighbourhood around its orbit.
(source: http://www.iau.org/public_press/news/release/iau0603/)
Where Are Asteroids?Where Are Asteroids?
(source: http://upload.wikimedia.org/wikipedia/commons/f/f3/InnerSolarSystem-en.png)
But Where Are They But Where Are They Right Now?Right Now?
(source: http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=1&orb=1#top)
Special Classifications for NEOs – Special Classifications for NEOs – AmorsAmors
(source: http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=1221&orb=1#top; see also http://www.cfa.harvard.edu/iau/lists/Amors.html )
Special Classifications for NEOs – Special Classifications for NEOs – ApollosApollos
(source: http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=1862&orb=1#top; see also http://www.cfa.harvard.edu/iau/lists/Apollos.html )
Special Classifications for NEOs – Special Classifications for NEOs – AtensAtens
(source: http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2062&orb=1#top; see also http://www.cfa.harvard.edu/iau/lists/Atens.html )
How Many Asteroids Are There?How Many Asteroids Are There?(source: http://www.wwu.edu/depts/skywise/a101_asteroids.html, corrected)(source: http://www.wwu.edu/depts/skywise/a101_asteroids.html, corrected)
dia (km)dia (km) ## tot vol kmtot vol km33
950950 11 4.5 4.5 ×× 10 1088
400400 11 3.4 3.4 ×× 10 1077
200200 1313 5.5 5.5 ×× 10 1077
100100 5050 2.6 2.6 ×× 10 1077
5050 130130 8.5 8.5 ×× 10 1066
2525 500500 4.1 4.1 ×× 10 1066
1010 3,2003,200 1.7 1.7 ×× 10 1066
55 18,00018,000 1.2 1.2 ×× 10 1066
2.52.5 96,00096,000 7.9 7.9 ×× 10 1055
11 1,000,0001,000,000 5.2 5.2 ×× 10 1055
Power-Law DistributionPower-Law Distribution(source: http://www.sdss.org/news/releases/20010605.edr.img9.html)(source: http://www.sdss.org/news/releases/20010605.edr.img9.html)
n ~ D-2.3
diameterdiameter ## impact energy*impact energy*
1 km1 km 11 5.4 5.4 ×× 10 1044 MT MT
100 m100 m 200200 8.3 MT8.3 MT
10 m10 m 40,00040,000 23 kT23 kT
1 m1 m 8,000,0008,000,000 10 tonnes TNT10 tonnes TNT
* http://www.lpl.arizona.edu/impacteffects/
Historical Impacts You’ve Heard OfHistorical Impacts You’ve Heard Of
Barringer49 ± 3 ka
Chicxulub64.98 ± 0.05 Ma
Historical Impacts You’ve Heard OfHistorical Impacts You’ve Heard Of
Tunguska6/30/1908
Craters You Can VisitCraters You Can Visit(source: www.unb.ca/passc/ImpactDatabase/NorthAmerica.html)
Decaturville, MO• 9 miles south of Camdenton on MO-5
• 6 km dia
• < 300 Ma
Odessa, TX• I-20 at exit 108
• 160 m dia
• < 50 ka
Sierra Madera, TX• 18 miles south of Ft Stockton on US-385
• 13 km dia
• < 100 Ma
Weaubleau–Osceola StructureWeaubleau–Osceola Structure(source: Dr Kevin Evans, Missouri State University [former SMSU])
• N 37°59’, W 93°38’ (possibly one of series of impacts along 38th parallel, including Decaturville)
• 19 km dia (4th largest in US and one of 50 largest on Earth)
• 340 Ma (middle Mississippian Period)
• impactor diameter ~370 m• ASKC SME is David Neuenschwander
Historical Impacts You Historical Impacts You Haven’tHaven’t Heard Of Heard Of
“Clovis Comet” 12.9 ka (http://www.pnas.org/cgi/content/abstract/0706977104v1)
• Tunguska-like event, but much larger, over northeastern North America
• partially destabilized Laurentide Ice Sheet, triggering Younger Dryas cooling; shockwave, thermal pulse, “extensive biomass burning”
• at least 17 species of megafauna went extinct
• Clovis culture disappeared; possible death of 2/3 of North American population
Tasman Sea, ~1500 AD (http://www.sciencenews.org/articles/20040306/bob8.asp)
• tsunami left deposits 130 m above sea level in eastern Australia, 150-220 m above sea level on Stewart Island/Rakiura, NZ
• 20 km dia, 150 m deep seafloor crater SW of NZ
• 1-km-wide asteroid impact
Historical Impacts You Historical Impacts You Haven’tHaven’t Heard Of Heard Of
Great Chicago Fire, 10/8/1871 (http://pdf.aiaa.org/preview/CDReadyMPDC04_865/PV2004_1419.pdf)
• fragments of Comet 3D/Biela
• also Peshtigo Fire (4,850 km², 1,200-2,500 deaths) and Port Huron Fire (similar size, 50 deaths)
Historical Impacts You Historical Impacts You Haven’tHaven’t Heard Of Heard Of
http://www.cedu.niu.edu/~henning/ChicagoFireWebQuest/fire2.jpg http://www.angelfire.com/mi2/gfmeteor/images/peshtigo1871.jpg
http://upload.wikimedia.org/wikipedia/commons/d/d5/CometBiela.jpg
Historical Impacts You Historical Impacts You Haven’tHaven’t Heard Of Heard OfKusaie (Kosrae), 1 Feb 1994 (“Satellites
Detect Record Meteor,” Sky & Telescope, June 1994)
• rocky body 15 meters in diameter traveling 15 km sec-1
• 110-kT explosion at 20 km altitude; visual magnitude -25
• pinpointed by 6 early-warning satellites to 164.1°E, 2.7°N; also seen by two fishermen
• events this size occur about once per decade somewhere on Earth
Most NEOs produce airbursts• volatile cometary material evaporates
• asteroids/meteoroids are often “rubble piles”
• Apollo asteroid 25143 Itokawa
(from Hayabusa probe)
(http://www.lib.utexas.edu/maps/australia/oceania_ref_2007.pdf)
Chicago, 26 March 2003 (source:
http://www-news.uchicago.edu/releases/04/040414.parkforest.shtml)
• estimated mass 900 kg; velocity 18 km sec-1
• fireball visible from Michigan, Illinois, Indiana and Missouri
• hundreds of fragments recovered from Chicago’s south suburbs
• KE= ½ mv2 indicates 36,000 kg TNT equivalent
Historical Impacts You Historical Impacts You Haven’tHaven’t Heard Of Heard Of
Historical Impacts You Historical Impacts You Haven’tHaven’t Heard Of Heard OfBBC headline,19 December 2004:
“Jakarta shaken by ‘meteor blast’”
• occurred during a terror alert and heightened security (“Operation Candle”)
• audible 60 km away (source: Townsville [Australia] Bulletin/Sun, URL not available)
(source: http://news.bbc.co.uk/2/hi/asia-pacific/4108697.stm)
Historical Impacts You Historical Impacts You Haven’tHaven’t Heard Of Heard Of
http://news.nationalgeographic.com/news/bigphotos/52624256.htmlPhotograph by Miguel Carrasco/La Razon/Reuters
Carangas, Peru, 16 September 2007 (source:
http://news.nationalgeographic.com/news/2007/09/070921-meteor-peru.html)
• crater 13 meters across, 3 meters deep
• ejecta thrown 250 meters
This Month’s Near-MissThis Month’s Near-Miss(source: http://neo.jpl.nasa.gov/ca/)
asteroid 2009 TU
• flew by at 0.002 AU = 0.8LD shortly before 7 PM CDT on Thu 8 Oct
• H = +27.3; Mv = +13.8; D ≈ 9.1–20m; v = 15.25 km sec-1
• airburst energy would have been ~300 kT (source: http://www.lpl.arizona.edu/impacteffects/)
This Month’s Near-MissThis Month’s Near-Miss(source: http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2009%20TU;orb=1)
Effects on Human HistoryEffects on Human History
• mass extinctions
• North American charismatic megafauna
• North American native culture/population
• Younger Dryas origin of diabetes?
The Black SwanThe Black Swan
• definition• the Fourth Quadrant• complexity of failure• geopolitical risk
The Black SwanThe Black Swan
Definition: “… a large-impact, hard-to-predict, and rare event beyond the realm of normal expectations.”
(source: http://en.wikipedia.org/wiki/Black_swan_theory)
Short version:
low-probability, high-effect events
The Fourth QuadrantThe Fourth Quadrant(adapted from http://www.edge.org/3rd_culture/taleb08/taleb08_index.html)
complex (magnitude of effect)
payoffs
Quadrant 3
quite robust to Black Swans
Quadrant 4
LIMITS OF STATISTICS; extreme fragility to Black
Swans
simple
(yes/no) payoffs
Quadrant 1
extremely robust to Black Swans
Quadrant 2
quite robust to Black Swans
application
domain
thin-tailed (Gaussian) probability structure
thick-tailed (power law) probability structure
The Complexity of FailureThe Complexity of Failurehttp://www.santafe.edu/research/publications/workingpapers/00-12-062.pdf
http://www.nasa.gov/columbia/home/CAIB_Vol1.html
The Fourth Quadrant in ActionThe Fourth Quadrant in Action(source: http://pajamasmedia.com/instapundit/86785/)
http://tipstrategies.com/archive/geography-of-jobs/
Geopolitical RiskGeopolitical Risk, or, or
The Meaning of It AllThe Meaning of It All
(with posthumous apologies to Richard Feynman)
Asteroid size distribution and composition combine with terrestrial realities such that:
• rare larger impacts mean frequent smaller impacts
• smaller impact ranges are in the tens of kilotons and are usually airbursts, but …
• so are nuclear weapons, and the explosions look exactly the same, in a world of …
• “hostile capabilit[ies] among various actors with whom we have conflicting interests” (source: http://www.outsidethebeltway.com/archives/2008/04/iran_war_drums_beating/)
Global Catastrophic Risk:Global Catastrophic Risk:Taxonomy/OrganizationTaxonomy/Organization
Nature
UnintendedConsequences
HostileActs
Global Catastrophic Risk:Global Catastrophic Risk:Observation Selection EffectsObservation Selection Effects
Empirical (A Posteriori) Distribution
A Priori Distribution
Distribution of impact craters, shock glasses, and so on
Distribution of near-Earth objects and Earth-crossing comets
(modified from Global Catastrophic Risks, Table 6.1, page 125)
Beware of anthropic overconfidence bias!
Global Catastrophic Risk:Global Catastrophic Risk:Observation Selection EffectsObservation Selection Effects
Empirical (A Posteriori) Distribution
A Priori Distribution
Distribution of impact craters, shock glasses, and so on
Distribution of near-Earth objects and Earth-crossing comets
Human history affected:
North American survivors, diabetics, etc
Human history ended?
How to Save CivilizationHow to Save Civilization
Think Globally• detection
• prediction
• mitigation
Act Locally• Powell Observatory• asteroid imaging• orbit refinement• asteroid discovery
How to Save Civilization:How to Save Civilization:what what notnot to do to do
“We should act incrementally as prudent risk minimizers and pursue any effective no-regrets options. We do not have to wait for the formulation and acceptance of grand strategies, for the emergence of global consensual understanding, or for the universal adoption of more rational approaches.”
DetectionDetectionAutomated searches - telescopes in 0.5-1 m size range
w/CCD cameras:
• Lincoln Near-Earth Asteroid Research (LINEAR) telescope at Socorro, NM
• Near-Earth Asteroid Tracking (NEAT) telescope at Haleakala, Maui, Hawaii
• Spacewatch telescope at Kitt Peak• Lowell Observatory Near-Earth Object Search
(LONEOS) telescope at Flagstaff• Catalina Sky Survey 3 telescopes (2 in Tucson, 1 in
Australia)• Japanese Spaceguard Association (JSGA) telescope in
Japan• Asiago DLR Asteroid Survey (ADAS) telescope in Italy
Mitigation – Torino ScaleMitigation – Torino Scale(source: http://neo.jpl.nasa.gov/torino_scale.html)
no hazard white zone 0
normal green zone 1
meriting attention by astronomers
yellow zone 2 – 4
threatening orange zone 5 – 7
certain collisions red zone 8 – 10
Powell ObservatoryPowell ObservatoryLewis-Young Park, Louisburg, KSLewis-Young Park, Louisburg, KS
Powell ObservatoryPowell Observatory30” Ruisinger Telescope30” Ruisinger Telescope
• Newtonian ReflectorNewtonian Reflector• diameter of aluminized area of mirror = 737 mmdiameter of aluminized area of mirror = 737 mm• focal length = 3760 mm (f/5.1)focal length = 3760 mm (f/5.1)• magnifications 68x – 538x depending on eyepiecemagnifications 68x – 538x depending on eyepiece• details 500’ across on Moondetails 500’ across on Moon
• Light grasp = 11,000 Light grasp = 11,000 × human eye× human eye• limiting visual magnitude = +17limiting visual magnitude = +17• 20 times fainter than Pluto20 times fainter than Pluto• > 100,000,000 stars; thousands of galaxies> 100,000,000 stars; thousands of galaxies• Sun at 8,000 light-yearsSun at 8,000 light-years• activates cone cells in retina – color visionactivates cone cells in retina – color vision
ASKC Astro Imaging CenterASKC Astro Imaging CenterPowell Observatory, Louisburg, KS; 38°38'46" N, 94°41'59"
Asteroid Imaging CameraAsteroid Imaging Camera
Asteroid 2004 QT24Asteroid 2004 QT24PHA (Potentially Hazardous Asteroid); NEO (Near Earth Object)
H = +18.27, diameter ~760 m, period 440 daysEarth MOID = .0074617 AU = 1,116,300 km = 2.9LD
impact energy 23,400 MT (if solid rock at 17 km sec-1)
(source: Dick Trentman, ASKC)
(source: http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2004%20QT24;orb=1)
Asteroid 2004 QT24Asteroid 2004 QT24tracking images taken from Powell Observatory AIC, 4/22/2005
(source: Dick Trentman, ASKC)
Asteroid 2004 QT24Asteroid 2004 QT24tracking images taken from Powell Observatory AIC, 4/22/2005
(source: Dick Trentman, ASKC)
Asteroid 2004 QT24Asteroid 2004 QT24tracking images taken from Powell Observatory AIC, 4/22/2005
(source: Dick Trentman, ASKC)
Asteroid 2004 QT24Asteroid 2004 QT24tracking images taken from Powell Observatory AIC, 4/22/2005
(source: Dick Trentman, ASKC)
Saving CivilizationSaving Civilizationthe ASKC Way
1. get nightly list of objects of high interest from MPC2. take 10-100 images of that area of sky3. digitally combine images into 3 groups, “blink” them4. if something jumps, compare with known direction/speed5. astrometric software does position and speed analysis6. send data only (no images) back to MPC 7. they do computation to extend known segment of orbit8. then rate object on Torino scale (0-10)
(source: Mitch Glaze, ASKC)
How is this saving civilization?How is this saving civilization?With our data, the Minor Planet Center …
• Updates its library of all known NEOs’ orbital and physical data.• Correlates new discoveries with “lost” asteroids.• Provides accurate predictions of future NEO orbital motion.• Identifies PHAs (potentially hazardous asteroids).• Monitors changes to NEO orbits due to various influences.
Major accomplishments …
• Starting in 2001, Powell became the second most productive observatory in the world (official designation IAUC/MPC #649) for NEO confirmation and tracking.
• In 2004, Powell was specifically requested by the MPC to image “killer asteroid” 2004 MN4, later known as 99942 Apophis, because of the large aperture (30”) Ruisinger telescope and the quality of its previous work.
• Currently, Powell has over 9,300 NEO observations, second only to the federally-funded Lowell Observatory.
(source: AJ Eaton, ASKC)
Also, We’ve Discovered A FewAlso, We’ve Discovered A Few
… … and here it isand here it is
H = +13.3; Mv = +16.9; diameter ~7.5 km; period 4 yrs 8 mosblackbody surface temperature 235°K, –38°C, –36°Fsurface gravity ≈0.00035 g; 100 lb on Earth = 9/16 oz
(source: http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2000%20VG38;orb=1;cov=0;log=0#orb)
Monday, October 6, 2008Monday, October 6, 2008Humanity’s first successful prediction of an asteroid impact!
Asteroid 2008 TC3• discovered ~20 hours before impact by
Catalina Sky Survey 1.5m telescope on Mt Lemmon, AZ
• 1-5 meters in diameter traveling 12.8 km sec-1; entered atmosphere at 19° angle
• 1-2 kT explosion at 20 km altitude; visual magnitude -13; observed by KLM aircraft crew 1,400 km away; detected by infrasound array in Kenya
• see http://en.wikipedia.org/wiki/2008_TC3 and http://orbit.psi.edu/?q=node/22
Impact ImagesImpact Images(http://commons.wikimedia.org/wiki/File:ELG_webcam_record_of_2008_TC3_frame_0005.png)(http://commons.wikimedia.org/wiki/File:ELG_webcam_record_of_2008_TC3_frame_0005.png)
30 seconds beforeduring
20 seconds after
Impact AnimationImpact Animation
http://www.youtube.com/watch?v=Cxa2PUluqVU
2008 TC3’s Final Orbit2008 TC3’s Final Orbit(source: http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2008%20TC3;orb=1)
2008 TC3’s Fragments Found!2008 TC3’s Fragments Found!(source: http://www.nature.com/nature/journal/v458/n7237/full/nature07920.html)
• exploded at 37 km altitude; no macroscopic fragments were expected to survive• but 47 meteorites found; total mass 3.95 kg• parent body named Almahata Sitta (“Station Six,” train station with eyewitnesses)• achondrite, a polymict ureilite, ultra-fine-grained and porous, with large
carbonaceous grains• asteroid was F class, made of material so fragile it was not previously represented
in meteorite collections
(source: http://www.sciam.com/article.cfm?id=asteroid-meteorite-sudan-fireball)
2008 TC3’s Fragments Found!2008 TC3’s Fragments Found!(source: http://apod.nasa.gov/apod/ap090328.html)
Harry Turtledove, Call Your OfficeHarry Turtledove, Call Your Office(source: https://www.cia.gov/library/publications/the-world-factbook/reference_maps/pdf/physical_world.pdf)
actual path
what if?
what if?what if?
Join the ASKC!Join the ASKC!What We Do• Monthly meetings with great speakers and knowledgeable club members
• Operate Powell Observatory – training is always available
• Operate Warkoczewski Observatory at UMKC (Friday nights)
• Heart of America Star Party every year at dark-sky site near Butler, MO
What You Get to Do• Members can use the “Louisburg Community Telescope” (actually 2
telescopes, 16” and 12½” reflectors) any time
• Become a “keyholder” at Powell Observatory – training is always available
• Get access to members-only “dark-sky site”
• Help refine asteroid orbits – save civilization!
http://www.askc.org/