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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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

Input

Output