Placing Our Solar System in Context with the Spitzer Space

TelescopeMichael 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 (UC-Berkeley), 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. Moro-Martin (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).

10-30 Myr old IRAC.

CAI

Fo

rmat

ion?

Chr

ondr

ules

?

Terr

estr

ial P

lane

ts?

3-10 Myr old IRAC.

Silverstone et al. (ApJ, Submitted);See also Mamajek et al. 2004; Weinberger et al. 2004; Metchev et al. 2004.

Dust from 0.3-3 AU evolves on timescales comparable to the cessation

of accretion (cf. C2D)MIR

Out of a sample of > 70 stars 3-30 Myr old, 5 optically-thick disks, and no optically-thin disks.

Silverstone et al. (ApJ, in press)

Cf. Wolk and Walter, 1996; Kenyon and Hartmann, 1995; Prato and Simon, 1995; Skrutskie et al. 1990.

... Transition time from thick to thinis < 1 Myr (cf. C2D, next 2 slides)

MIR

Disk timescales - from C2D

* Some wTTs do have disksnot 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

Padgett et al., in prep; Cieza et al., in prep.

Big RED circle: has disk

Some disks have inner holes

Cieza et al., in prep.

* 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”

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

Examples of warm debris (> 100 K)around Sun-like stars are rare (a

few %)

Bouwman et al. (in preparation); cf. Beichman et al. (2005); Song et al. (2005), Chen et al. (2005); Kenyon & Bromley (2004)

MIR

...but more common around stars < 100 Myr.

Stauffer et al. 2005; Stauffer et al. poster, this meeting

Solar-type stars in the Pleiades (age ~ 100 Myr)5 cases of excess at 24 & 33 m; 2-3 probably real (not bkg)

Detecting Cool Gas in Disks

is HARD!

Gorti & Hollenbach (2004); also Najita et al.

poster, this mtg

GASG

AS

MA

S

DUST MASS

GAS DETECTABLE HERE

=> 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

GAS

Gas disk lifetimes appear to be < 10 Myr.

MMSN = minimum mass solar nebula

Cool Debris Disks (T < 100 K) are fairlycommon (15-20 %) around Sun-like stars

Kim et al. 2005,Hillenbrand et al. poster, this mtg;cf. Bryden et al. 2005

30+- 10 Myr45 to ??? AU~1x10-7 Msun

700+- 300 Myr 20 to <100 AU~6.9x10-8 Msun

FIR

... evidence for ? Dynamically hot outer planetesimal belts

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

HR 8907

FIR

Statistics of FEPS 33 m Detections N/M/F-IR

See also Bryden et al. (2005)

NB: less common at ages > 300 Myr than 70 m (~ 50 K) detections

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

Radius (AU)

Life

time

(Myr

)

3-10

10-30

30-100

100-300

300-1000

1000-3000

< 0.1 0.3-1.0 1-10 30-100

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 m 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