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Near Earth Asteroids and Kuiper Belt Objects. Geoff Bower. Jewitt 2000. Tunguska. 50 km diameter. Fatalities. Estimates of Impact Rate. Lunar cratering D ~ E^1/3.5 D ~ 3 – 100 km N(D) ~ D^-1.7 Survey back to 3 Gyr One 10 km impact/10^8 y Telescopic surveys. NEA Search Requirements.
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Near Earth Asteroidsand Kuiper Belt Objects Geoff Bower The Transient Universe: AY 250 Spring 2007
The Transient Universe: AY 250 Spring 2007 Jewitt 2000
Tunguska 50 km diameter The Transient Universe: AY 250 Spring 2007
Fatalities The Transient Universe: AY 250 Spring 2007
Estimates of Impact Rate • Lunar cratering • D ~ E^1/3.5 • D ~ 3 – 100 km • N(D) ~ D^-1.7 • Survey back to 3 Gyr • One 10 km impact/10^8 y • Telescopic surveys The Transient Universe: AY 250 Spring 2007
NEA Search Requirements • Depth • For small, distant objects • Large FOV • For completeness • High resolution • Cadence • For accurate orbits • Rapid data reduction The Transient Universe: AY 250 Spring 2007
Sedna Discovery Brown et al 2004 4.6”/3.1 hour R=20.5 Palomar Oschin telescope The Transient Universe: AY 250 Spring 2007
Inner Oort Cloud Object Sedna Brown et al 2004 76 – 480 AU The Transient Universe: AY 250 Spring 2007
Eris/UB313The Largest Dwarf Planet 1.4”/hr Brown et al 2005 R=18 mag 2400 +/ 100 km diameter 96 AU The Transient Universe: AY 250 Spring 2007
KBO Distribution The Transient Universe: AY 250 Spring 2007
KBO Variability 6.7 hour period Sheppard & Jewitt The Transient Universe: AY 250 Spring 2007
Colors of KBOs Jewitt & Luu 2001 The Transient Universe: AY 250 Spring 2007
10 km size threshold ~10 objects w/size 1000 km N (> size) ~ size^-3 10^7 new objects discovered 1 km size threshold 10^10 new objects The Predictions for P* and LSST The Transient Universe: AY 250 Spring 2007
Pan Starrs 10^7 objects 5 y / 10 sec integrations ~ 10^7 observations 1 object/observation LSST 10^10 objects 1000 objects/observation Transient/Rock Confusion The Transient Universe: AY 250 Spring 2007
Transient/Rock Confusion II • Proper motion • Inclination to ecliptic • Catalog • Color • Multi-wavelength activity • Universal cadence The Transient Universe: AY 250 Spring 2007