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 (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 Formation? Chrondrules? Terrestrial Planets? 3-10 Myr old IRAC. Silverstone et al. (ApJ, Submitted); See also Mamajek et al. 2004; Weinberger et al. 2004; Metchev et al Dust from 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 Transition time from thick to thin is < 1 Myr (cf. C2D, next 2 slides) MIR
Disk timescales - from C2D * 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 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 GAS GAS MAS DUST MASS GAS DETECTABLE HERE
=> No gas rich disk (> 0.1 Mjup) detected. => 20 stars with ages 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 fairly common (15-20 %) around Sun-like stars Kim et al. 2005, Hillenbrand et al. poster, this mtg; cf. Bryden et al Myr 45 to ??? AU ~1x10 -7 M sun Myr 20 to <100 AU ~6.9x10 -8 M sun 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) Lifetime (Myr) <
FEPS posters at this meeting Silverstone et al. » Young, warm debris disks Mamajek et al. » HD (from Hines et al. in press) Najita et al. » Limits on circumstellar gas Stauffer et al. » Pleiades stars with 24 & 33 m excesses Hillenbrand et al. » Old, cold debris disks (from Kim et al. 2005) Backman et al. » To-date FEPS results summary