Transcript Document 7618560

Placing Our Solar System in Context
with the Spitzer Space Telescope
Michael R. Meyer
Steward Observatory, The University of Arizona
D. Backman (NASA-Ames, D.P.I.) , S.V.W. Beckwith (STScI), J. Bouwman
(MPIA), T. Brooke (Caltech), J.M. Carpenter (Caltech), M. Cohen (UCBerkeley), U. Gorti (NASA-Ames), T. Henning (MPIA), L. Hillenbrand
(Caltech, D.P.I.), D. Hines (SSI), D. Hollenbach (NASA-Ames), J. Lunine
(LPL), J.S. Kim (Steward), R. Malhotra (LPL), E. Mamajek (CfA), A. MoroMartin (Princeton ), P. Morris (SSC), J. Najita (NOAO), D. Padgett (SSC), I.
Pascucci (Steward), J. Rodmann (MPIA), W. Schlingman (Steward), M.
Silverstone (Steward), D. Soderblom (STScI), J.R. Stauffer (SSC), B.
Stobie (Steward), S. Strom (NOAO), D. Watson (Rochester), S.
Weidenschilling (PSI), S. Wolf (MPIA), and E. Young (Steward).
Dust from 0.3-3 AU evolves on timescales
comparable to the cessation of accretion (cf. C2D)
MIR
Terrestrial Planets?
Chrondrules?
CAI Formation?
Silverstone et al.
(ApJ, Submitted);
See also Mamajek et al.
2004; Weinberger et al.
2004; Metchev et al.
2004.
3-10 Myr old IRAC.
10-30 Myr old IRAC.
... Transition time from thick to thin
is < 1 Myr (cf. C2D, next 2 slides)
MIR
Silverstone et al.
(ApJ, in press)
Cf. Wolk and Walter,
1996; Kenyon and
Hartmann, 1995; Prato
and Simon, 1995;
Skrutskie et al. 1990.
Out of a sample of
> 70 stars 3-30 Myr
old, 5 optically-thick
disks, and no
optically-thin disks.
Disk timescales - from C2D
Big RED circle: has disk
Padgett et al., in prep; Cieza et al., in prep.
* Some wTTs do have disks
not previously detected,
BUT only the younger ones
( ages < 3 to 6 Myr)
[ages are ~ uncertain]
* 1/2 the young ones lack
disks, even at age 0.8 to 1.5
Myr
* Age is NOT the only
variable
Some disks have inner holes
* Some wTTs have
inner holes, but small
fraction of systems.
* May be cleared by
planet formation
* Infer that disk clearing
is fast
* Planet formation is
“fast or not at all”
Cieza et al., in prep.
Examples of warm debris (> 100 K)
around Sun-like stars are rare (a few %)
Warm debris (perhaps 4-6 AU)
around 30 Myr old sun-like star!
Hines et al. (ApJ, in press); Mamajek et
al. poster, this meeting.
MIR
...but more common around stars < 100 Myr.
MIR
Bouwman et al. (in preparation); cf. Beichman et al. (2005);
Song et al. (2005), Chen et al. (2005); Kenyon & Bromley (2004)
Solar-type stars in the Pleiades (age ~ 100 Myr)
5 cases of excess at 24 & 33 mm; 2-3 probably real (not bkg)
Stauffer et al. 2005; Stauffer et al. poster, this meeting
GAS
GAS MAS
GAS DETECTABLE HERE
Detecting
Cool Gas
in Disks
is HARD!
Gorti &
Hollenbach
(2004); also
Najita et al.
poster, this mtg
DUST MASS
Gas disk lifetimes appear to be < 10 Myr.
GAS
=> No gas
rich disk
(> 0.1 Mjup)
detected.
=> 20 stars
with ages
3-100 Myr
Hollenbach et al. (ApJ, 2005); Najita et al. poster, this mtg
MMSN = minimum mass solar nebula
Cool Debris Disks (T < 100 K) are fairly
common (15-20 %) around Sun-like stars
FIR
30+- 10 Myr
45 to ??? AU
~1x10-7 Msun
700+- 300 Myr
20 to <100 AU
~6.9x10-8 Msun
Kim et al. 2005,
Hillenbrand et al.
poster, this mtg;
cf. Bryden et al.
2005
FIR
... evidence for ?
Dynamically hot outer
planetesimal belts

HR 8907
Lack of interior
planetesimal belts

Clues to the physical state
of the remnant disk (e.g.
Najita & Williams 2005)

Kim et al. 2005; Hillenbrand et al. poster, this mtg
Statistics of FEPS 33 mm Detections
N/M/F-IR
NB: less common at ages > 300 Myr than 70 mm (~ 50 K) detections
See also Bryden et al. (2005)
History of our solar system’s dust disk -- are strong old excesses
= extrasolar Late Heavy Bombardments?
Backman et al. in prep; cf. Gomes et al. (2005); Strom et al. (2005),
Levison et al. (PPV), Kenyon & Bromley (2004).
FEPS Preliminary Results: Debris Disk Lifetimes
< 0.1
0.3-1.0
3-10
10-30
30-100
100-300
300-1000
1000-3000


1-10
30-100
Radius (AU)
FEPS posters at this meeting

63.18 Silverstone et al.
» Young, warm debris disks

63.48 Mamajek et al.
» HD 12039 (from Hines et al. in press)

63.52 Najita et al.
» Limits on circumstellar gas

63.11 Stauffer et al.
» Pleiades stars with 24 & 33 mm excesses

63.28 Hillenbrand et al.
» Old, cold debris disks (from Kim et al. 2005)

63.31 Backman et al.
» To-date FEPS results summary