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| .p50 Moon formed 4.5Gya / Late Heavy Bombardment 3.9 Gya / life evidence 3.5 Gya / Oxygen 2.4 Gya / Eukariotes 2.0 Gya .p56 few known NEO until mid 1990s .p63 Eleanor "Glo" Helin 1932-2009 with Gene Shoemaker at Palomar Schmidt 1973 .p65 Gene and Carolyn Shoemaker to USGS Flagstaff, Helin to JPL .p65 1983 Tom Gehrels and Bob !McMillan, Spacewatch at Steward Obsv. near Tucson, 1989 2K*2K CCD .p69 1998 Spaceguard Goal, 90% of 1-2km NEO over next decad, presumed 14% albedo .p71 [[ https://doi.org/10.1016/j.icarus.2015.05.004 | Allan W. Harris 990 >1Km ]] .p73 [[ https://cneos.jpl.nasa.gov/stats/totals.html | NEA discovery graph ]] book as of 2011/08 .p75 LSST expected to find 90% of >140m objects over 70 years .p76 WISE 2009/12 to 2010/10, NEOWISE [[ https://science.jpl.nasa.gov/people/Mainzer/ | Amy Mainzer]] discovered 135 NEOs and 21 comets .p77 hypothetical NEO IR telescope at Venus distance could see more Aten class . |
Near Earth Objects
Finding Them Before They Find Us
Donald K. Yeomans 2013 Princeton 523.44 Yeo Tigard
Manager of NASA's Near-Earth Object Program Office at JPL. He was the Radio Science Team Chief for the Near-Earth Asteroid Rendezvous (NEAR) mission and currently he is the US Project Scientist for the Japanese Hayabusa.
- xiii 2013 Feb 15 Asteroid 2012 DA L-class, carbon dominated with calcium and aluminum inclusions, .44 albedo, 20x40m
- xiii 2013 Feb 15 Chelyabinsk fireball 23 km altitude 18m diameter 10000 tonnes
- xiii 1km asteroid every 500K years
p11 Amor: per 1.017 to 1.3 AU, ap < Mars ~ 1.5 AU
Apollo: per < 1.017 AU, semi > 1 AU
Aten: ap > 0.983 AU, semi < 1 AU
Atiras: ap < 0.983 AU, semi < 1 AU
p19 Neptune 30 AU, Kuiper 35AU to 50 AU (<0.1 Me), Oort >1K to 100K AU (1.6 LY) (4 to 80 Me)
- p33 Nice model of planetary formation/migration
- p44 Yarkowski, prograde rotation outward
- p45 YORP, uneven radiation changes rotation
- p50 Moon formed 4.5Gya / Late Heavy Bombardment 3.9 Gya / life evidence 3.5 Gya / Oxygen 2.4 Gya / Eukariotes 2.0 Gya
- p56 few known NEO until mid 1990s
- p63 Eleanor "Glo" Helin 1932-2009 with Gene Shoemaker at Palomar Schmidt 1973
- p65 Gene and Carolyn Shoemaker to USGS Flagstaff, Helin to JPL
p65 1983 Tom Gehrels and Bob McMillan, Spacewatch at Steward Obsv. near Tucson, 1989 2K*2K CCD
- p69 1998 Spaceguard Goal, 90% of 1-2km NEO over next decad, presumed 14% albedo
p73 NEA discovery graph book as of 2011/08
p75 LSST expected to find 90% of >140m objects over 70 years
p76 WISE 2009/12 to 2010/10, NEOWISE Amy Mainzer discovered 135 NEOs and 21 comets
- p77 hypothetical NEO IR telescope at Venus distance could see more Aten class