Interstellar and Solar System organic matter preserved in interplanetary dust

AbstractInterplanetary dust particles (IDPs) collected in the Earths stratosphere derive from collisions among asteroids and by the disruption and outgassing of short-period comets. Chondritic porous (CP) IDPs are among the most primitive Solar System materials. CP-IDPs have been linked to cometary parent bodies by their mineralogy, textures, C-content, and dynamical histories. CP-IDPs are fragile, fine-grained (< um) assemblages of anhydrous amorphous and crystalline silicates, oxides and sulfides bound together by abundant carbonaceous material. Ancient silicate, oxide, and SiC stardust grains exhibiting highly anomalous isotopic compositions are abundant in CP-IDPs, constituting 0.01-1% of the mass of the particles. The organic matter in CP-IDPs is isotopically anomalous, with enrichments in D/H reaching 50x the terrestrial SMOW value and 15N/14N ratios up to 3x terrestrial standard compositions. These anomalies are indicative of low T (10-100 K) mass fractionation in cold molecular cloud or the outermost reaches of the protosolar disk. The organic matter shows distinct morphologies, including sub-um globules, bubbly textures, featureless, and with mineral inclusions. Infrared spectroscopy and mass spectrometry studies of organic matter in IDPs reveals diverse species including aliphatic and aromatic compounds. The organic matter with the highest isotopic anomalies appears to be richer in aliphatic compounds. These materials also bear similarities and differences with primitive, isotopically anomalous organic matter in carbonaceous chondrite meteorites. The diversity of the organic chemistry, morphology, and isotopic properties in IDPs and meteorites reflects variable preservation of interstellar/primordial components and Solar System processing. One unifying feature is the presence of sub-um isotopically anomalous organic globules among all primitive materials, including IDPs, meteorites, and comet Wild-2 samples returned by the Stardust mission. We will present an overview of the current state of understanding of the properties and origins of organic matter in primitive IDPs.

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Structural, chemical and isotopic examinations of interstellar organic matter extracted from meteorites and interstellar dust particles

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308021881 ◽

2008 ◽

Vol 4 (S251) ◽

pp. 333-334

Author(s):

Henner Busemann ◽

Conel M. O'D. Alexander ◽

Larry R. Nittler ◽

Rhonda M. Stroud ◽

Tom J. Zega ◽

...

Keyword(s):

Organic Matter ◽

Solar System ◽

Interstellar Dust ◽

Focused Ion Beam ◽

Secondary Ion Mass Spectrometry ◽

Ion Beam ◽

Carbonaceous Material ◽

Interplanetary Dust ◽

Dust Particles ◽

Interplanetary Dust Particles

AbstractMeteorites and Interplanetary Dust Particles (IDPs) are supposed to originate from asteroids and comets, sampling the most primitive bodies in the Solar System. They contain abundant carbonaceous material. Some of this, mostly insoluble organic matter (IOM), likely originated in the protosolar molecular cloud, based on spectral properties and H and N isotope characteristics. Together with cometary material returned with the Stardust mission, these samples provide a benchmark for models aiming to understand organic chemistry in the interstellar medium, as well as for mechanisms that secured the survival of these fragile molecules during Solar System formation. The carrier molecules of the isotope anomalies are largely unknown, although amorphous carbonaceous spheres, so-called nanoglobules, have been identified as carriers. We are using Secondary Ion Mass Spectrometry to identify isotopically anomalous material in meteoritic IOM and IDPs at a ~100-200 nm scale. Organics of most likely interstellar origin are then extracted with the Focused-Ion-Beam technique and prepared for synchrotron X-ray and Transmission Electron Microscopy. These experiments yield information on the character of the H- and N-bearing interstellar molecules: While the association of H and N isotope anomalies with nanoglobules could be confirmed, we have also identified amorphous, micron-sized monolithic grains. D-enrichments in meteoritic IOM appear not to be systematically associated with any specific functional groups, whereas 15N-rich material can be related to imine and nitrile functionality. The large 15N- enrichments observed here (δ15N > 1000 ‰) cannot be reconciled with models using interstellar ammonia ice reactions, and hence, provide new constraints for understanding the chemistry in cold interstellar clouds.

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Dome C ultracarbonaceous Antarctic micrometeorites

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731322 ◽

2018 ◽

Vol 609 ◽

pp. A65 ◽

Cited By ~ 20

Author(s):

E. Dartois ◽

C. Engrand ◽

J. Duprat ◽

M. Godard ◽

E. Charon ◽

...

Keyword(s):

Organic Matter ◽

Solar System ◽

Absorption Band ◽

Raman Spectra ◽

Interplanetary Dust ◽

Organic Component ◽

Dust Particles ◽

Interplanetary Dust Particles ◽

Lower Oxygen ◽

Carbonyl Absorption Band

Context. UltraCarbonaceous Antarctic MicroMeteorites (UCAMMs) represent a small fraction of interplanetary dust particles reaching the Earth’s surface and contain large amounts of an organic component not found elsewhere. They are most probably sampling a contribution from the outer regions of the solar system to the local interplanetary dust particle (IDP) flux. Aims. We characterize UCAMMs composition focusing on the organic matter, and compare the results to the insoluble organic matter (IOM) from primitive meteorites, IDPs, and the Earth. Methods. We acquired synchrotron infrared microspectroscopy (μFTIR) and μRaman spectra of eight UCAMMs from the Concordia/CSNSM collection, as well as N/C atomic ratios determined with an electron microprobe. Results. The spectra are dominated by an organic component with a low aliphatic CH versus aromatic C=C ratio, and a higher nitrogen fraction and lower oxygen fraction compared to carbonaceous chondrites and IDPs. The UCAMMs carbonyl absorption band is in agreement with a ketone or aldehyde functional group. Some of the IR and Raman spectra show a C≡N band corresponding to a nitrile. The absorption band profile from 1400 to 1100 cm-1 is compatible with the presence of C-N bondings in the carbonaceous network, and is spectrally different from that reported in meteorite IOM. We confirm that the silicate-to-carbon content in UCAMMs is well below that reported in IDPs and meteorites. Together with the high nitrogen abundance relative to carbon building the organic matter matrix, the most likely scenario for the formation of UCAMMs occurs via physicochemical mechanisms taking place in a cold nitrogen rich environment, like the surface of icy parent bodies in the outer solar system. The composition of UCAMMs provides an additional hint of the presence of a heliocentric positive gradient in the C/Si and N/C abundance ratios in the solar system protoplanetary disc evolution.

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Presolar grains in the Solar System: Connections to stellar and interstellar organics

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308021911 ◽

2008 ◽

Vol 4 (S251) ◽

pp. 343-344

Author(s):

Larry R. Nittler

Keyword(s):

Organic Matter ◽

Solar System ◽

Interplanetary Dust ◽

Asymptotic Giant Branch ◽

Dust Particles ◽

Interplanetary Dust Particles ◽

Molecular Chemistry ◽

Stellar Outflows ◽

Isotopic Compositions ◽

Polycyclic Aromatic

AbstractA small fraction of primitive meteorites and interplanetary dust particles (IDPs) consists of grains of presolar stardust. These grains have extremely unusual isotopic compositions, relative to all other planetary materials, indicating that they condensed in the outflows and explosions of prior generations of stars (Clayton & Nittler 2004). Identified presolar grain types include silicate, oxide and carbonaceous phases. The latter include graphitic carbon, diamond and SiC. Although many of these phases do not have a direct connection to organic chemistry, this is not true of the graphitic spherules. Many of these, with isotopic compositions indicating an origin in C-rich asymptotic giant branch (AGB) star outflows, have a structure consisting of naonocrystalline cores surrounded by well-graphitized C (Bernatowicz et al. 1996). The cores include isotopically anomalous polycyclic aromatic hydrocarbons (Messenger et al. 1998) and represent a link between molecular chemistry and dust condensation in stellar outflows. Meteorites and IDPs also contain abundant isotopically anomalous organic matter, including distinct organic grains, some of which probably formed in stellar outflows and/or the interstellar medium (ISM) (Busemann et al. 2006, Floss et al. 2004). In some IDPs, deuterium- and 15N-enriched organic matter is closely associated with presolar silicate grains (Messenger et al. 2005, Nguyen et al. 2007), suggesting an association in the ISM prior to Solar System formation.

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The origin of organic matter in the solar system: evidence from the interplanetary dust particles

Geochimica et Cosmochimica Acta ◽

10.1016/j.gca.2003.09.001 ◽

2003 ◽

Vol 67 (24) ◽

pp. 4791-4806 ◽

Cited By ~ 154

Author(s):

G.J Flynn ◽

L.P Keller ◽

M Feser ◽

S Wirick ◽

C Jacobsen

Keyword(s):

Organic Matter ◽

Solar System ◽

Interplanetary Dust ◽

Dust Particles ◽

Interplanetary Dust Particles

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A Common Origin for Organics in Meteorites and Comets: Was It Interstellar?

Proceedings of the International Astronomical Union ◽

10.1017/s1743921311025051 ◽

2011 ◽

Vol 7 (S280) ◽

pp. 288-301 ◽

Cited By ~ 8

Author(s):

Conel M. O'D. Alexander

Keyword(s):

Organic Matter ◽

Solar System ◽

Organic Material ◽

Protoplanetary Disks ◽

Interplanetary Dust ◽

Dust Particles ◽

Soluble Organic Matter ◽

Interplanetary Dust Particles ◽

Cold Environments ◽

Insoluble Material

AbstractThe insoluble organic material preserved in primitive chondritic meteorites shares many similarities with the refractory organic material in interplanetary dust particles and comets, suggesting that there is a genetic link between the organic matter in objects that formed between ~3 AU and ~30 AU from the Sun. These similarities include large D and 15N enrichments in bulk and even more extreme enrichments in isotopic hotspots. The enrichments attest to formation in very cold environments, either in the outer Solar System or the protosolar molecular cloud. There are many properties of this organic material that are consistent with an interstellar origin, but a Solar System origin cannot be ruled out. Similar organic material is presumably an important component of most protoplanetary disks, and heating or sputtering of this material would be a source of PAHs in disks. The soluble organic matter was more heavily effected by processes on the chondritic parent bodies than the insoluble material. Amino acids, for instance, probably formed by reaction of ketones and aldehydes with NH3 and HCN. The accretion of the relatively volatile NH3 and HCN, presumably in ices, strengthens the chondrite-comet connection. However, unlike most comets the water in chondrites, when it was accreted, had D/H ratios that were similar to or depleted relative to Earth.

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The Question of Presolar Components within Interplanetary Dust Particles (IDPs) Collected in the Stratosphere

Highlights of Astronomy ◽

10.1017/s1539299600012752 ◽

2002 ◽

Vol 12 ◽

pp. 34-37 ◽

Cited By ~ 1

Author(s):

John P. Bradley

Keyword(s):

Solar Nebula ◽

Carbonaceous Material ◽

Building Blocks ◽

Interplanetary Dust ◽

Dust Particles ◽

Space Observatory ◽

Interplanetary Dust Particles ◽

Infrared Space Observatory ◽

Fine Grained ◽

Astronomical Dust

AbstractInterplanetary dust particles (IDPs) are from asteroids and comets, and they are the smallest and most fine-grained meteoritic objects available for laboratory investigation. Cometary IDPs are of special significance because they are presently the only samples of comets, and comets are expected to be enriched in preserved solar nebula and presolar components. These components may include not only cosmically rare refractory circumstellar grains(e.g. SiC) that are recovered from meteorites but also cosmically abundant interstellar silicates and carbonaceous grains that were the fundamental building blocks of the Solar System. D/H ratios measured in IDPs are consistent with the survival of interstellar carbonaceous material, and some IDPs contain glassy grains with properties similar to those of interstellar “amorphous silicates”. Submicrometer forsterite and enstatite crystals in IDPs resemble circumstellar silicates detected by the Infrared Space Observatory (ISO). ISO also detected a broad ~ 23 µm feature around several stars, and a similar feature observed in IDP spectra is due to submicrometer FeNi sulfide grains, suggesting that sulfide grains may be a significant constituent of astronomical dust.

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What can pre-solar grains tell us about the solar nebula?

Proceedings of the International Astronomical Union ◽

10.1017/s1743921307010964 ◽

2006 ◽

Vol 2 (14) ◽

pp. 353-356 ◽

Cited By ~ 1

Author(s):

Gary R. Huss ◽

Bruce T. Draine

Keyword(s):

Solar System ◽

Solar Nebula ◽

Interplanetary Dust ◽

Radiation Environment ◽

Dust Particles ◽

Early Solar System ◽

Interplanetary Dust Particles ◽

Fine Grained ◽

Isotopic Compositions ◽

Relative Abundances

AbstractSeveral types of pre-solar grains, grains that existed prior to solar system formation, have been found in the fine-grained components of primitive meteorites, interplanetary dust particles (IDPs), and comet samples. Known pre-solar components have isotopic compositions that reflect formation from the ejecta of evolved stars. Other pre-solar materials may have isotopic compositions very similar to solar system materials, making their identification as pre-solar grains problematic. Pre-solar materials exhibit a range of chemical and thermal resistance, so their relative abundances can be used to probe the conditions in the solar nebula. Detailed information on the relative abundances of pre-solar and solar-system materials can provide information on the temperatures, radiation environment, and degree of radial mixing in the early solar system.

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Physical and Mineralogical Properties of Anhydrous Interplanetary Dust Particles in the Analytical Electron Microscope

International Astronomical Union Colloquium ◽

10.1017/s0252921100066495 ◽

1991 ◽

Vol 126 ◽

pp. 63-70

Author(s):

J. P. Bradley

Keyword(s):

Carbonaceous Material ◽

Interplanetary Dust ◽

Coarse Grained ◽

Dust Particles ◽

Interplanetary Dust Particles ◽

Electron Microscopic ◽

Atmospheric Entry ◽

Fine Grained ◽

Microscopic Studies ◽

Solar Flare Tracks

AbstractThe fine grained mineralogy and petrography of anhydrous “pyroxene” and “olivine” classes of chondritic interplanetary dust have been investigated by numerous electron microscopic studies. The “pyroxene” interplanetary dust particles (IDPs) are porous, unequilibrated assemblages of mineral grains, metal, glass, and carbonaceous material. They contain enstatite whiskers, FeNi carbides, and high-Mn olivines and pyroxenes, all of which are likely to be well preserved products of nebular gas reactions. Solar flare tracks are prominent in most “pyroxene” IDPs, indicating that they were not strongly heated during atmospheric entry. The “olivine” IDPs are coarse grained, equilibrated mineral assemblages that have probably experienced strong heating. Since most “olivine” IDPs do not contain tracks, it is possible that this heating occurred during atmospheric entry.

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Dust Around Young Stars: How Related to Solar System Dust?

Highlights of Astronomy ◽

10.1017/s1539299600011503 ◽

1995 ◽

Vol 10 ◽

pp. 351-392 ◽

Cited By ~ 3

Author(s):

Martha S. Hanner

Keyword(s):

Solar System ◽

Interplanetary Space ◽

Circumstellar Disks ◽

Theoretical Work ◽

Interplanetary Dust ◽

Young Stars ◽

Dust Particles ◽

Interplanetary Dust Particles ◽

Technical Advances ◽

Dust Disks

Study of the dust in circumstellar disks around young stars is currently an extremely active area in astronomy. There is little doubt that accretion disks are a natural part of protostellar evolution. Much recent observational and theoretical work is giving us a clearer picture of the physical conditions in dust disks and their evolutionary progression. IRAS observations revealed that many main-sequence stars, such as p Pictoris, have circumstellar disks. But whether these disks are related to planetary formation is not yet understood.A portion of the dust in disks around young stars ultimately may be incorporated into planetary systems. Thus, study of the dust in our own solar system complements the remote sensing of protostellar regions and aids in reconstructing the evolutionary history of the dust. Since comets formed in the cold outer regions of the solar nebula, they may contain intact interstellar grains. As the comets lose material during passage through the warm inner solar system, some of these grains will be released into interplanetary space. Technical advances now allow analysis of individual micrometer or smaller grains in interplanetary dust particles and primitive meteorite samples. Isotopic anomalies and patterns of crystal growth in these particles are yielding tantalizing clues about the interstellar material incorporated into these solar system samples.

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