in solar system materials

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Gervais Cooper
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1 The major noble gas components in solar system materials H. BUSEMANN School of Earth, Atmospheric and Environmental Sciences, University of Manchester, UK He Ar Kr Ne Xe (glow of gas discharge lamps) there is nothing like rare gases (C. Allègre)

2 WORKSHOP SCIENTIFIC CASE & AIM 1. contribution of stellar nucleosynthesis to Galactic chemical evolution => >interstellar t 3 He/ 4 He, constraining i GCE & stellar models 2. observed isotopic fractionation in interstellar clouds 3. chemical models of gaseous and solid-state isotopic chemistry 4. isotopic anomalies in meteorites and IDPs (including the Stardust sample) => planetary noble gases in meteorites, Phase Q carrier phase 5. presolar grains => Ne-E, Xe-HL, Kr-s, Xe-s isotopes in comets => cometary (?) noble gases in IDPs & comet Wild 2 7. observations and models of isotopic fractionation in proto-planetary disks, 8. new results from Herschel and ALMA 9. proposed list of key astronomical observations and laboratory sample measurements to be made => wish list

$elemental fractionation He Ne Ar$ Kr Xe Number of Atoms 10 18

3 Noble Gases in Meteorites Huge elemental fractionation He Ne Ar Kr Xe Number of Atoms Number of Atoms in g of CI Material He Ne Ar Kr Xe solid material (10 μg CI chondrite) Mass Number Rare(!) gases solar system => easy to detect exotic, isotopically anomalous components => discovery of presolar grains!

4 Noble Gases in Meteorites Huge elemental fractionation solar ( 84 Kr/ 132 Xe) solar ~20 ( 84 K/ Kr/ 132 Xe) Q ~ ( 4 He/ 132 Xe) solar ~2E9 ( 4 He/ 132 Xe) Q ~400 planetary atmospheres & (p meteoritic noble gases not linked planetary => primordially trapped e) solar (element / Xe) / (ele ement / Xe planetary atmospheres 1E-3 1E-4 1E-5 meteorites Sun Jupiter Venus 1E-6 Earth Mars 1E-7 4 He 20 Ne 36 Ar Element bulk Grosnaja Q Grosnaja 84 Kr 132 Xe

5 Noble Gases in Meteorites Not planetary Venus/Earth/Mars Atmospheres 1. Trapping of solar gases 2. Hydrodynamic escape e.g., Pepin 1991, Hunten, Zahnle 1993 or: Cometary source? e.g., Owen & Bar-Nun 2000 and others Jupiter and friends 1. Accretion of nebula gas & Icy planetesimals 2. He & Ne segregation Meteorites 1. Trapping of gases on presolar icy grains at low T in molecular cloud 2. Formation of carbonaceous molecules / mantles / material Huss 1987, Sandford 1998 Many more suggestions: (anomalous) adsorption, exposure to plasma, irradiation, ion trapping, Raleigh fractionation during loss etc. often without complete model of where & when (but mostly in solar system) ) e.g. Marrocchi et al. 2011

6 Noble Gases in Meteorites Isotopic fractionation identical Q-Ar-Xe isotopic compositions minor variations in Q- Ne & He all elements (incl. N?) isotopically i heavier than solar composition No single fractionation for elements & isotopes e.g.ozima et al Ne/ 22 Ne 14 SW SEP Q[ 10 air solar "trapped" Ne "exotic" Ne Cosmic Rays: "spallation" Ne Ne sp Ne/ 22 Ne

7 Phase Q unknown & ill-defined d Q for "quintessence" Lewis et al ("aether", fifth classical element after earth, fire, water & air) "operational" definition: survives demineralisation (HF/HCl ), but releases noble gases upon oxidation (HNO 3, HClO 4, H 2 O 2 ) +HF/HCl /CsF insoluble organic matter (IOM) typically few weight% of bulk

2000 present in all primitive meteorite classes including enstatite chondrites present in ureilites,

8 Phase Q - Af few knowns carbonaceous Ott 1981 almost mass less (<< 1 wt% bulk) high gas release temperatures (mostly C) Huss et al enormous concentrations Busemann et al present in all primitive meteorite classes including enstatite chondrites present in ureilites, primitive achondrites Q-Ne isotopic signature in cometary Stardust Marty et al not found in planetary atmospheres / interiors comet Wild 2

9 Many more unknowns: The Carrier(s) no idea generally accepted or reproduces all observations adsorption site /carbonaceous matter Frick et al. 1978, Wacker et al./zadnik et al. 1985/9 C active capture & anomalous adsorption Hohenberg et al carbon-coated silicates Nichols et al UV-irradiated icy grain mantles Sandford et al plasma trapping in presolar diamonds Matsuda & Yoshida 2001

10 Many more unknowns: The Carrier(s) no idea generally accepted or reproduces all observations fullerenes Becker et al. 2000, Wilson et al graphitic crystallites Smith & Buseck 2001 nanotubes Heymann & Vis 1998 Garvie & Buseck 2004 macromolecular aromatic IOM Marrocchi et al. 2005, 2011 Pyridine associated to presolar grains? Amari et al. 2003, carriers? Gros & Anders 1977, Busemann et al. 2000, Verchovsky et al. 2002, Amari et al. 2010

molecules in protosolar cloud ubiquitous throughout solar system (local origin unlikely) homogeneous mixture of phase Q and presolar grains 3 He/ 4 He

11 Phase Q - Protosolar origin? Huss & Alexander 1987, Sandford 1998 simulation experiment at low T. trapped Ar, Kr, Xe depletion of He/Ne due to poor adsorption at low T. formation of large Q-like? molecules in protosolar cloud ubiquitous throughout solar system (local origin unlikely) homogeneous mixture of phase Q and presolar grains 3 He/ 4 He in phase Q ~1.2 x 10-4, similar to Big Bang, ISM, presolar grains => most likely pre-d-burning He ( 3 He/ 4 He in present-day Sun ~ 46x ) => more difficult to explain post-d burning fractionation Busemann et al. 2001, Heber et al. 2009, Ozima et al. 2011

Presolar Grains Silicon Carbide "exotic"

stellar nucleosynthesis models most trapped

12 Presolar Grains Silicon Carbide "exotic" components (1960s) discovery of presolar grains (1980s): diamonds, graphite, SiC (all at ppm level) comparison with & input for stellar nucleosynthesis models most trapped He & Ne in chondrites presolar! Podosek et al Ne-G Ne-R

13 Interstellar He trapped onboard the MIR space station => An interstellar heritage in solar system materials Solar system s velocity relative to local ISM (LISM) 25 km/s P. C. Frisch

14 3 He/ 4 He in the local ISM aim: improved 3 He/ 4 He in present-day LISM constrains GCE models ( 3 He net production vs. 3 He plateau ) => The 3 He problem ISM planetary nebulae x 10-4 Balser et al = standard stellar models ISM HII regions x 10-4 e.g. Bania et al => Extra mixing, Cool bottom processing?

15 Experiment COLLISA - COLLection of InterStellar Atoms trapping of neutral ISM-He in foils (as SW during Apollo missions) on Mir Space Station

16 Only neutral atoms from the ISM shutters open only in direction of neutral flux closed when directed along velocity of spacecraft no terrestrial contamination grids at 6 kev no ions of magnetospheric origin Komza collectors on Spektr modul

17 Trapping in BeO on CuBe substrate thin BeO layer on CuBe, 4 x ~200 cm 2 exposure time ~60h Interstellar particle flux significant trapping at >60 km/s

2002 (tritiogenic) 3 He blank correction:

18 Previous experiments - stepwise heating 3 He/ 4 He = ( ) x 10-4 Salerno et al (tritiogenic) 3 He blank correction: ~50 % release by stepwise etching with HF 10 min HF

19 Closed system stepwise etching mass spec acid MIR foil

20 4.5 MIR foil released noble gases 3 He 4 He Ne 30k k Gas amo ount [10 6 atoms] average system blank 20k 15k 10k 5k average system 0 blank etch progress average system blank

21 MIR foil vs. Blank foil 3 He 4 He 20 Ne k 80 x k Gas amo ount [10 6 atoms] k 50 15k k 20 5k etch progress 0

22 MIR foil Interstellar 3 He/ 4 He 4 4 blank corrected 5 5mostgasrich gas-rich steps (95% of He total ) 3 6 He [10 atoms] [ 3 He] = x 10-4 x [ 4 He] η 3 /η 4 = ( 3 He/ 4 He) LISM system blank: 0.88± He [10 6 atoms]

23 3 He/ 4 He in the LISM MIR foil (50 cm 2 ) x 10-4 Busemann et al. 2006, ApJ online etching MIR foil (130 cm 2 ) x10-4 Salerno et al stepwise heating pickup ions x 10-4 Gloeckler & Geiss 1996

24 3 He/ 4 He and GCE models SWICS Pick-up ions Chiappini et al. 2002, 93% Tosi 1988, 93% Tosi 1988, 100% Romano et al Big Bang Jupiter, meteorites MIR Foils oven => extra -mixing in almost 100 % of all low-mass giant stars thermohaline mixing Romano / Charbonnel & Lagarde 2009

25 3 He/ 4 He and GCE models SWICS Pick-up ions Chiappini et al. 2002, 93% Tosi 1988, 93% Romano et al Big Bang Tosi 1988, 100% Jupiter, MIR meteorites Foils etching => extra -mixing in almost 100 % of all low-mass giant stars thermohaline mixing Romano / Charbonnel & Lagarde 2009

Mostly unconstrained Spectroscopy: not yet a convincing detection of any noble gas sublimating from a cometary nucleus Bockelée-Morvan et al.

26 Noble Gases in Comets Delivery of volatiles into inner solar system (atmospheres, terr. water, late veneer?): H 2 O, N, Noble gases Ices: diagnostic of formation temperature /region Bar-Nun & Owen Cometary solids: similar to asteroids? Phase Q even in outer solar system? Mostly unconstrained Spectroscopy: not yet a convincing detection of any noble gas sublimating from a cometary nucleus Bockelée-Morvan et al upper limits for Ne & Ar Stern et al. 2000, Krasnopolsky et al => Stard st? He / Ne detectable M t t l 2008 => Stardust? He / Ne detectable Marty et al Problem: aerogel & small gas amounts => Interplanetary Dust particles? Problem: unknown origin & small gas amounts

27 Timed Grigg-Skjellerup Dust Collection (GSC) JFC particles represent 85% of the total mass influx at Earth Nesvorný et al Earth passes through dust trail of short-period comet 26P/GS => fresh direct injection in April 2003 Messenger 2002 "at least several, up to 50% of background IDP flux >40 μm from GS" short cosmic-ray exposure ages / low solar wind huge abundances of presolar grains large isotope anomalies (D, 15 N) Busemann et al new mineral Brownleeite Unusual Ne (Novae origin?) Pepin et al. 2011

28 IDP Xenon measurements with RELAX 10 Kehm et al normal IDPs: Ø ~20-30 μm (5-17 ng) 000) atoms/1 132 Xe (a 5 "blank" all data ±SD blank ~6100 atoms 0 IDP "TCN" terr. contam. Cold blank run

29 IDP Xenon measurements with RELAX ) atoms/1 132 Xe (a 5 0 Au hot blank Au hot blank Au hot blank run this work: blank ~500 atoms Au hot blank "blank" all data ±SD blank ~6100 atoms cold blank ±SD before / after each sample & air calib.

30 IDP Xenon measurements with RELAX ) atoms/1 132 Xe (a 5 GSC IDPs normal IDPs "blank" all data ±SD 0 run cold blank ±SD before / after each sample & air calib.

31 10 IDP Xenon measurements with RELAX 3x Al 2 O 3 & FeO fragm. Ø ~2-4 μm GSC IDPs normal IDPs 000) L2054 Cl4+L Cl Xe (atoms/1 reheat L2036 Cl9 AI2 L2036 Cl20 v3p3 reheat L2036 Cl20 v3p4 reheat L2036 Cl9 v2p1 reheat L2054 Cl1 F1 reheat reheat reheat 0 run

32 Noble Gases in Grigg-Skjellerup Collection (GSC-) )IDPs Xenon: FeO-FeNi-/Al 2 O 3 -rich GSC-IDPs (measured together) 4f fragments, Ø ~2-4 μm rocket fuel? Brownlee 1976 Al 2 O 3 No Xenon: 1 x chondritic porous GSC-IDP 4 x chondritic porous non-gsc-idps (10 fragments) Neon: in fine rocket grained fuel? Al 2 O 3 from L2054 cluster FeNi/FeO 4 Al 2 O 3 Al 2 O 3 Palma & Nakamura-Messenger pers. comm.

33 Primordial Cometary Q-Xe Meteorites HF/HCl-residues 3 x 10-7 ccstp/g 132 Xe Busemann et al Phase Q ( 1%) 3 x 10-5 ccstp/g 132 Xe measured in the 4 IDPs 2 x 10-7 ccstp/g => consistent, if 1wt% phase Q mixed into IDP(s) Stardust 0.1 ccstp/g 20 Ne-Q in Stardust Marty et al ( 20 Ne/ 132 Xe) Q ~ Busemann et al => 3 x 10-2 ccstp/g 132 Xe in Stardust Exposure to Solar Wind? unlikely: years exposure to SW at 1 AU (=> lower limit!) required

34 Wishlist Solar System materials in the laboratory What is Phase Q? Can we separate it? => D/H, 15 N/ 14 N, XANES, TEM => Origin? Noble gas incorporation process? Protosolar? Xe-HL, separation of L & H? Origin of noble gases in presolar diamonds? Complete (He-Xe) trapped noble gas characterisation of cometary IDPs & Antarctic micrometeorites / comet Wild 2 dust Spectroscopy Cometary noble gas abundances => Delivery of volatiles to terrestrial planets (atmospheres, late veneer), transport of material into outer solar system, irradiation?

Comet Science Goals II

Comet Science Goals II {questions for goals} Don Brownlee Did the events postulated by the Nice Hypothesis really happen? Were there wide-spread solar system wide impact events that were coeval with the