AAS 196th Meeting, June 2000
Session 36. Exploring Dust and the ISM with SIRTF
Topical Session Oral, Wednesday, June 7, 2000, 8:30-10:00am, 10:45am-12:30pm, Highland B/J

[Previous] | [Session 36] | [Next]

[36.03] Circumstellar Debris Disks and SIRTF

D. E. Backman (F&M College / NASA-Ames)

At least 15% of nearby main sequence stars are found to have far-IR excesses representing thermal emission from optically thin dust clouds. Famous prototypes of this class of objects include the Vega and beta Pictoris systems. Because destruction times for observed grains are much shorter than the system ages, the dust is known to be ``2nd generation" material released recently from hypothetical asteroid or comet parent bodies and not primordial grains persisting since system formation. The best local analogs to the main sequence debris disk systems are the inner solar system's zodiacal dust cloud and a presumed dust component of the Kuiper Belt. Planetary masses are probably required to drive planetesimals into shattering collisions and star-grazing orbits that produce dust, thus debris disks may allow inference of presence and location of planets.

SIRTF will give us much-improved understanding of the frequency of debris disks around field main sequence stars, as well as the amount, size and composition of dust grains versus stellar age. This will help place our solar system into context of evolution of planetary material around normal stars.

The author(s) of this abstract have provided an email address for comments about the abstract: backman@ssa1.arc.nasa.gov

[Previous] | [Session 36] | [Next]