Placing Our Solar System in Context with the Spitzer Space Telescope

1
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).

2
Dust from 0.3-3 AU evolves on timescales
comparable to the cessation of accretion (cf.
C2D)
MIR
Silverstone et al. (ApJ, Submitted) See also
Mamajek et al. 2004 Weinberger et al. 2004
Metchev et al. 2004.
Chrondrules?
CAI Formation?
3-10 Myr old IRAC.
Terrestrial Planets?
10-30 Myr old IRAC.
3
... Transition time from thick to thinis lt 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 gt 70 stars 3-30 Myr old, 5
optically-thick disks, and no optically-thin
disks.
4
Disk timescales - from C2D
Some wTTs do have disks not previously
detected, BUT only the younger ones ( ages lt 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
Big RED circle has disk
Padgett et al., in prep Cieza et al., in prep.
5
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.
6
Examples of warm debris (gt 100 K)around Sun-like
stars are rare (a few )
MIR
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.
7
...but more common around stars lt 100 Myr.
MIR
Bouwman et al. (in preparation) cf. Beichman
et al. (2005) Song et al. (2005), Chen et al.
(2005) Kenyon Bromley (2004)
8
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
9
GAS
Detecting Cool Gas in Disks is HARD! Gorti
Hollenbach (2004) also Najita et al. poster,
this mtg
GAS DETECTABLE HERE
GAS MAS
DUST MASS
10
Gas disk lifetimes appear to be lt 10 Myr.
GAS
gt No gas rich disk (gt 0.1 Mjup) detected. gt
20 stars with ages 3-100 Myr
Hollenbach et al. (ApJ, 2005) Najita et al.
poster, this mtg
11
MMSN minimum mass solar nebula
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Cool Debris Disks (T lt 100 K) are fairlycommon
(15-20 ) around Sun-like stars
FIR
30- 10 Myr 45 to ??? AU 1x10-7 Msun
Kim et al. 2005, Hillenbrand et al. poster, this
mtg cf. Bryden et al. 2005
700- 300 Myr 20 to lt100 AU 6.9x10-8 Msun
13
... evidence for ?
FIR

• Dynamically hot outer planetesimal belts
• Lack of interior planetesimal belts
• Clues to the physical state of the remnant disk
  (e.g. Najita Williams 2005)

HR 8907

Kim et al. 2005 Hillenbrand et al. poster, this
mtg
14
Statistics of FEPS 33 ?m Detections
N/M/F-IR
NB less common at ages gt 300 Myr than 70 mm (
50 K) detections
See also Bryden et al. (2005)
15
History of our solar systems 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).
16
FEPS Preliminary Results Debris Disk Lifetimes
Radius (AU)
lt 0.1 0.3-1.0 1-10 30-100
3-10
Lifetime (Myr)
10-30
?
30-100
?
100-300
300-1000
1000-3000
17
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