Ge/Ay133

Can we study extrasolar Kuiper Belts?

Pic, A5V star AU Mic, M1Ve star

Impossible to see any exo-KBOs themselves, but…

How do we find debris disks?

Model has 0.1 Mmoon of30 m size dust grainsin a disk from 30–60 AUBars are 3 Model based on disksaround A stars

Spitzer Data (FEPS team)

Meyer et al., ApJS, 154, 422

What have far-IR SED surveys found?:Overall decay consistent with erosional evolution, fluctuations dominated by large collisions?

Rieke et al., ApJ, 620, 1010

So, when rings are seen around >10 Myr old stars… the dust must be made in place.

• CSO/HST have reached similar conclusions about structure of the disk around Fomalhaut and how it is generated. Is there a planet required to maintain it?

Marsh et al. – ApJ, Feb. 2005Kalas, Graham, & Clampin –

HST, Nature, June 2005

Vegaarcsec

arcsec

IRAM Plateau de Bure 1.3 mm

Wilner et al. 2002

Vega simulation – Marc Kuchner (GSFC)

What about “exo-zodii’s? That is, dust in ~1 AU range?

Rare!

Only one convincing case so far, in large aperture searches. Need to get closer to the star….

Beichman et al., ApJ, 626, 1061

Keck

Interferometer

What about gas?-Most searches negative, but “right” tracers (H2, C II) difficult to observe- Sharp rings suggestive of small amount of gas- Falling evaporative bodies? (next page)

FEBs = Falling Evaporative Bodies

See transient redshited absoprtion against stellar continuum. Evaporating comets?For the brightest sources (e.g. Pic), you can actually image things like Na I line emission and map the disk.

Next time: What can comets tell us about the early S.S.?

Deep Impact (Comet Tempel 1)

Comet Hale-Bopp