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De-aggregation and Ejection of Sub-surface Fresh(?) PSN Material GMC ISM Cometary Dust Poorly Understood Process of Chemical and Gravitational Aggregation #1, occurring in T ≤ 1 Myr ~1 um Proto-Solar Nebula 30 um Ices - C, H, O, N Dust - Mg, Si, Fe, S Ca, O, Al, C, … P.U.P.C.G.A. #2, occurring in T ≤ 10 Myr Origin = Solar nebula Deep Impact ~5 km T
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T1 Ejecta
(Oort Cloud)
(Typical JFC)
Extending the Results of the Spitzer-Deep Impact Experiment to Other Comets and Exo-Systems
C.M. Lisse (JHU-Applied Physics Laboratory)
16 um Ejecta Imaging
Poorly Understood Process of Chemical and Gravitational Aggregation #1, occurring in T ≤ 1 MyrProto-Solar Nebula
GMC ISM Cometary Dust
DeepImpact
De-aggregation and Ejection of Sub-surface Fresh(?) PSN Material
•Ices - C, H, O, N•Dust - Mg, Si, Fe, S
Ca, O, Al, C, …P.U.P.C.G.A. #2, occurring in T ≤ 10 Myr
Icy Dirtball Comet Nucleus
~5 km
T<400K, P < 1kPa
30 um
~1 um
Best-Fit LinearSum
PAHs (Soot, Exhaust)
Pyroxenes (Rock)
Spitzer IRS I+45 Min
Sulfides (Fool’s Gold)
Olivines (Rock)
Carbonates (Chalk)
(Pre
-Pos
t)/P
re =
Eje
cta/
Pre
-Impa
ct C
oma
(95% C.L. = 1.13)
Lisse et al. 2006
Amorphous Carbon (Soot)
Phyllosilicates (Clay)
344 Spectral PointsSNR 5 - 30 (22 error bars error bars)95% C.L.
= 1.13Simultaneous 5- 35 um> 16 Sharp Features
Water Ice
Water Gas
Fire, Mud, & Ice : Tempel 1 Contains Xtal Silicates, Annealed at T > 1000K + Carbonates & Clays - Formed via Interaction with Water + Ices - Stable Only Below 200 K
CrystalSilicates Carbonates
ClaysComets
Parent Body Aqueous Alteration Over 4.5 Gyr (1) Impulsive Cratering (2) Long Term Water Vapor Processing
Radial Mixing of PSN Material. From inside the orbit of Mercury to outside the orbit of Neptune (turn-off when giant planet cores form)
SST-IRS P/Tempel 1 Ejecta Spectrum Compared to Comets, Exo-Systems. - -Similar Spectra Due to Presence of Silicates, PAHs, Water, Sulfides.
- Differences Due to Relative Compositions, T, Particle Size
Comets Hale-Bopp, SW3, SW1 Disk Systems HD100546, HD69830, HD113766
10 Myr Be9V YSO w/ Disk Cavity
~15 Myr F3/F5 YSO
2-10 Gyr K0V w/ 3 Neptunes
“Spectral Fingerprints” of Cometary IR MineralogyT1 Spectral Model applied to other systems fits spectra well, extends results to Spitzer, ISO database. We can now dig down below the dominant silicate emissions to find other species.
Hale-Bopp : No Fe-rich olivine. Much more water ice and amorphous carbon. Carbonates, clay.SW1, SW3 : Much amorphous silicates, Mg-rich olivine. Only water gas for SW3, ice for SW1.
JFC SW-3 BFragment(SST; Sitkoet al. 2007)
Amorph CarbonPAHs
1.47 AU
JFC/CentaurSW-1 Coma(SST; Stansberryet al. 2005)
Lisse et al. 2007
5.7 AU
JFC Tempel 1 Ejecta (SST; Lisse et al. 2006)
Sulfides
1.5 AU
Smectite (clay)
Oort CloudHale-Bopp Coma (ISO; Crovisier et al. 1997)) Water Ice
2.8 AU
Pyroxenes
Pyroxenes
Carbonates
Carbonates
Olivines
OlivinesOlivines
Abundance of Cometary Water Ice vs. Gas Follows Water Ice Stability in Solar System
(rapidly ejectedInterior material)
(water ice rapidly sublimating)
(water ice stable)
Silicate Trends?(work in progress)
Pyroxene content is high for comets and HD100546,low for asteroidal debris disks
Relative amount of crystalline pyroxene increases from SW1, SW3 to Tempel 1. Tempel 1 appears most ”processed”. Hale-Bopp probably formed early, but why SW3 so “fresh”? Deep interior material, or bodies formed in PSN at different times 1- 10(?) Myr and places (4 - 50 AU)?
cometary
asteroidal
“Mature” HD69830 •K0V, T = 5400 K, 2 - 10 Gyr old, 12 pc distant•3 Neptune Sized Planets @ 0.08, 0.16, 0.63 AU
K0V, 12 pc
“Near-solar” star. Small, icy, ephemeral dust replenished by ongoing fragmentation. S.S. analogue : ~30 km radius P/D asteroid disrupted @ 1 AU. Karins/Veritas 5-8 Mya?
Lisse et al. 2007
T~ 400 K
Olivine Super-rich
Sulfides absent
PAHs absent
Pyrox all crystalline
Carbon attenuated
Water Ice
Carbonates
Super Comet or Asteroid?
Asteroidal Dust BeltLisse et al. 2007
DC
B
Beichman et al. 2005
Lovis et al. 2006
HD113766 : Mainly has Mg-rich olivine, Fe-rich sulfides, and xtal pyroxene. Little carbonates, clays, PAHs, or amorphous carbon present. Similar to S-type asteroid. NOT an older HD100546.
HD100546 : Comet-like. Especially rich in Mg-rich olivine and amorphous pyroxene, water ice. We find the dust to be at ~13 AU, consistent with the inner disk cavity edge of Grady et al. 2005.
Comparative IR Mineralogy of Young Stellar Objects
PAHs
Sulfides
HD100546 Disk Herbig Be9V >10 Myr
Clays
HD113766 Disk F3/F5 ~16 Myr
Amorph Carbon
Sulfides
X
PyroxenesPyroxenes
OlivinesOlivines
Water Ice
Carbonates
Lisse et al. 2007
Conclusions• We have obtained good fits to the 5- 35 um mid-IR spectra of comets HaleBopp, SW3, and
SW1 using the Deep-Impact -T1 ejecta model.
• Silicates, PAHs, water, and sulfides are found in abundance in all studied systems.
• We find the water content of the comets is gaseous inside the ice line, solid outside it, following the solid ice stability in the solar system.
• The relative amount of pyroxene decreases as the systems become processed into asteroidal material. In the comets, crystal pyroxene may increase with time of formation.
• We find emission from HD69830 (K0V, 2-10 Gy, ~0.5 Lsolar) dominated by highly processed dust from disruption of a ~ 30 km P or D-type body.
• We find emission from HD100546 (Be9V, > 10 My, 22-26 Lsolar) dominated by primitive nebular material at ~13 AU, at the disk inner cavity wall of Grady et al.
• We find emission from HD113766 (F3/F5, ~15 My, 4.4 Lsolar) dominated by processed dust from disruption of an ~S-type, terrestrial planet forming?) body at 2.2 AU.
=> Disks can be either primordial nebulae (cometary?) or due to stochastic collisions of coherent small bodies (asteroidal?).
Parameters Derivable From the DI Experiment
•Bulk, Average Composition of Ejected Dust–Obtained from features at set wavelengths–Allows search for comparable species in other systems
•Temperature of Dust Components at 1.5 AU–Obtained from short/long wavelength amplitude, feature –No modeling required–Yields location of dust in exo-systems from observed T’s
•Particle Size Distribution of Ejected Dust–Obtained from feature/continuum ratio–Unusual narrowly peaked distribution 0.1 - 10 um
Comets r(AU) Water Ice/Gas Silicates Carbonates Clays PAHs SulfidesTempel 1 1.51 Ice & O:P = 1 Magnesite & Yes Yes YesJFC Gas fxtalo = 0.7 Siderite(SST, 5-35um) (Impact) fxtalp = 0.9
SW3 1.47 Abundant O:P = 1.6 Some No Yes YesJFC Water Gas fxtalo = 0.3 Siderite(SST, 5-35um) (Near-Sun) fxtalp = 0.6
HaleBopp 2.8 Abundant O:P = 1.3 Abundant Yes Yes YesOort Cloud Water Ice fxtalo = 0.7 Magnesite &(ISO, 5-40um) (Beyond Ice fxtalp = 0.7 Siderite Line)
SW1 5.8 Abundant O:P ~ 3.2 Some No Yes? SomeCentaur/JFC Ice (BYI) fxtalo = 0.3 Siderite(SST, 7-35um) fxtalp = 0.5
Exo-systems r(AU) Water Ice/Gas Silicates Carbonates Clays PAHs Sulfides HD100546 ~13 AU Abundant O:P = 0.8 Magnesite Yes YES YesBe9V, ≥ 10 My (103pc) Ice & Water fxtalo = 1.0(ISO, 5-40um)fxtalp = 0.3
HD113766 ~1.8 AU Some O:P = 2.4 None ~None No YesF3/F5, ~16 My (131pc) Ice fxtalo = 0.7(SST, 5-35um) fxtalp = 1.0
HD69830 ~1 AU Some O:P = 2.8 ??? None No? NoK0V, 2 - 10 Gy (12pc) Ice fxtal = 0.8(SST, 7-35um) fxtalp = 0.8
Potential Reasons Potential Reasons for Deep for Deep
Impact/STARDUST Impact/STARDUST Differences in Differences in
Carbonate, Carbonate, Phyllosilicate Phyllosilicate MineralogyMineralogy
•Cometary Diversity - Differences in Formation Time, Location, Evolutionary History
(e.g. Tempel 1 rather processed and old, Wild2 rather young)
•Aqueous Alteration at the one DI Location sampled in depth
•Modelling Errors in Studyng the DI-Spitzer Data - CaO/CaOH? CH4.C2, C3?
•Stardust Small # Statistics to Date, Aerogel Obscuration
•Cold Excavation (DI) vs. Hot Aerogel Capture (STARDUST)
•Differences in surface vs. interior material - DI burrowed through a surface mantle layer
to different material underneath. Carbonates known to be UV photodissociated.
ImpactWild 2-like Areas?
RaisedLayers
Dep
ress
ion
R.L.
(1) Good Evidence Much of the Original ISM Material Has Been Reworked(ISM = amorphous silicates, abundant PAHs).
(2) Expected PSN Species from the Equilibrium Condensation Sequence :
- Metal (Al, Mg, Ti) Oxides- Olivines- Pyroxenes- Fe/Ni metal- (Na,K) Feldspars- Fe Sulfides- Phylosilicates
(after Lewis, 1995)
Atomic Abundances2 error bars for the relative measures are ± 20%.
Diamonds = Tempel 1, Triangles = Hale-Bopp, Squares = HD100546.
Orgueil CI Orgueil CI MeteoriteMeteorite
Tempel 1 Best Fit Model Atom Abundances Are Consistent with Solar for the Refractory Elements
SunSun
0.42 : 0.58 : 3.9 : 1.0 : 0.88 : 0.79 : 0.29 : 0.054 : ≤ 0.085 [x 106] H : C : O : Si : Mg : Fe : S : Ca : Al
(H, C, O Depleted, Mostly in Volatiles)
Water Gas
PAHs
Spitzer IRS I+45 Min Sulfides
Carbonates
Eje
cta
Em
issi
vity
- S
ilica
te B
estF
it M
odel
Lisse et al. 2006
Amorph Carbon
Water Ice
Carbonates
Non-DI Measures in Comets/IDPsNon-DI Measures in Comets/IDPs • Bregmann et al. 1987 Halley IR• Clark et al (1987) Halley in situ
(PIA, PUMA)• Sanford et al. 1984, 1986 IDP
chemistry, crystallography
YSO : 1/2 of all ISO spectraYSO : 1/2 of all ISO spectra•Ceccarelli et al. 2002•Chiavassa et al. 2005
Potential Reasons for DI/SD Potential Reasons for DI/SD DiffDiff
• Cometary Diversity• Aqueous Alteration at (1) DI Location• Modelling Errors - CaO/CaOH?• Stardust Small # Statistics• Cold Excavation vs. Hot Aerogelç
ImpactWild 2-like Areas?
RaisedLayers
Dep
ress
ion
R.L.
Tempel 1 Bulk Ejecta TemperaturesImplications : folivine ~ fpyroxene; Oliv Mg-rich, 70% xtal, Pyrx Fe/Ca-rich, 90% xtal; 8% Phyllosilicates; 5% Carbonates Mg-Fe rich, not Ca; PAHs at 1000 ppm; S bound in Fe-rich sulfides; H2O ice at 4% level; abundant amorphous C
Derived from the Best-Fit End-Member Model to the I+45m Spitzer T1-DI Ejecta Spectrum Species Weighted Density M.W. Nmoles. Model Tmax Model 2 Surface Area (g cm-3) (rel.) (oK) if removed Amorph Olivine (MgFeSiO4) 0.16 3.6 172 0.33 340 5.04 Forsterite (Mg2SiO4) 0.31 3.2 140 0.70 340 4.08 Fayalite (Fe2SiO4) 0.085 4.3 204 0.18 340 1.39 Amorph Pyroxene (MgFeSi2O6) 0.048 3.5 232 0.07 340 1.48 FerroSilite (Fe2Si2O6) 0.33 4.0 264 0.50 295 8.82 Diopside (CaMgSi2O6) 0.115 3.3 216 0.18 340 1.83 OrthoEnstatite (Mg2Si2O6) 0.10 3.2 200 0.16 340 1.70 Niningerite (Mg50Fe50S) 0.16 4.5 72 0.97 340 2.52 PAH (C10H14) 0.045 1.0 <178> 0.025 N/A 1.44 Water Ice (H2O) 0.045 1.0 18 0.25 220 1.32 Amorph Carbon (C) 0.075 2.5 12 1.60 390 15.2 Smectite Notronite 0.145 2.3 496 0.07 340 3.77 Na0.33Fe2(Si,Al)4O10(OH)2 * 3H2O Magnesite (MgCO3) 0.033 3.1 84 0.12 340 1.33 Siderite (FeCO3) 0.050 3.9 116 0.17 340 1.76 Nmoles(i) ~ Density(i)/Molecular Weight(i) * Surface Area Weighting(i); ± 10% errors on the abundances (2 ).
2 at 95 % confidence limit = 1.13
<---
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D C
ompl
iant
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SST-IRS P/Tempel 1 Ejecta Difference Spectrum vs. ISO-SWS C/Hale-Bopp, YSO HD100546
•Formed in Giant Planet Region•Resides in Outer Solar System Today
•Formed in Kuiper Belt•Resides in Inner Solar System
YSO with Rich Dusty Disk
Sun
PAHs
Silicates
Sulfides
Carbonates
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