the transient universe: ay 250 spring 2007 near earth asteroids and kuiper belt objects geoff bower

The Transient Universe: AY 250 Spring 2007

Near Earth Asteroidsand Kuiper Belt Objects

Geoff Bower

The Transient Universe: AY 250 Spring 2007 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

• Depth– For small, distant objects

• Large FOV– For completeness

• High resolution

• Cadence– For accurate orbits

• Rapid data reduction


Sedna Discovery

Brown et al 20044.6”/3.1 hourR=20.5

Palomar Oschin telescope


Inner Oort Cloud Object

SednaBrown et al 2004

76 – 480 AU


Eris/UB313The Largest Dwarf Planet

1.4”/hrBrown et al 2005R=18 mag 2400 +/ 100 km diameter

96 AU


KBO Distribution


KBO Variability

Sheppard & Jewitt

6.7 hour period


Colors of KBOs

Jewitt & Luu 2001


The Predictions for P* and LSST

• 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


Transient/Rock Confusion

• 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 II

• Proper motion

• Inclination to ecliptic

• Catalog

• Color

• Multi-wavelength activity

• Universal cadence

the transient universe: ay 250 spring 2007 near earth asteroids and kuiper belt objects geoff bower

Documents

transient universe

au slide

diameter slide

objectsobservation slide

hour period slide

kbo distribution slide

palomar oschin telescope

new objects