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11 results on '"K. Nakamura-Messenger"'

3. The operational environment and rotational acceleration of asteroid (101955) Bennu from OSIRIS-REx observations

Author

C. W. Hergenrother, C. K. Maleszewski, M. C. Nolan, J.-Y. Li, C. Y. Drouet d’Aubigny, F. C. Shelly, E. S. Howell, T. R. Kareta, M. R. M. Izawa, M. A. Barucci, E. B. Bierhaus, S. R. Chesley, B. E. Clark, E. J. Christensen, D. N. DellaGiustina, S. Fornasier, D. R. Golish, C. M. Hartzell, B. Rizk, D. J. Scheeres, P. H. Smith, X.-D. Zou, D. S. Lauretta, Jason Peter Dworkin, D.E. Highsmith, J. Small, D. Vokrouhlický, N.E. Bowles, E. Brown, K.L. Donaldson Hanna, T. Warren, C. Brunet, R.A. Chicoine, S. Desjardins, D. Gaudreau, T. Haltigin, S. Millington-Veloza, A. Rubi, J. Aponte, N. Gorius, A. Lunsford, B. Allen, J. Grindlay, D. Guevel, D. Hoak, J. Hong, D.L. Schrader, J. Bayron, O. Golubov, P. Sánchez, J. Stromberg, M. Hirabayashi, C.M. Hartzell, S. Oliver, M. Rascon, A. Harch, J. Joseph, S. Squyres, D. Richardson, J.P. Emery, L. McGraw, R. Ghent, R.P. Binzel, M.M. Al Asad, C.L. Johnson, L. Philpott, H.C.M. Susorney, E.A. Cloutis, R.D. Hanna, H.C. Connolly Jr, F. Ciceri, A.R. Hildebrand, E.-M. Ibrahim, L. Breitenfeld, T. Glotch, A.D. Rogers, B.E. Clark, S. Ferrone, C.A. Thomas, H. Campins, Y. Fernandez, W. Chang, A. Cheuvront, D. Trang, S. Tachibana, H. Yurimoto, J.R. Brucato, G. Poggiali, M. Pajola, E. Dotto, E. Mazzotta Epifani, M.K. Crombie, C. Lantz, M.R.M. Izawa, J. de Leon, J. Licandro, J.L.Rizos Garcia, S. Clemett, K. Thomas-Keprta, S. Van wal, M. Yoshikawa, J. Bellerose, S. Bhaskaran, C. Boyles, S.R. Chesley, C.M. Elder, D. Farnocchia, A. Harbison, B. Kennedy, A. Knight, N. Martinez-Vlasoff, N. Mastrodemos, T. McElrath, W. Owen, R. Park, B. Rush, L. Swanson, Y. Takahashi, D. Velez, K. Yetter, C. Thayer, C. Adam, P. Antreasian, J. Bauman, C. Bryan, B. Carcich, M. Corvin, J. Geeraert, J. Hoffman, J.M. Leonard, E. Lessac-Chenen, A. Levine, J. McAdams, L. McCarthy, D. Nelson, B. Page, J. Pelgrift, E. Sahr, K. Stakkestad, D. Stanbridge, D. Wibben, B. Williams, K. Williams, P. Wolff, P. Hayne, D. Kubitschek, M.A. Barucci, J.D.P. Deshapriya, M. Fulchignoni, P. Hasselmann, F. Merlin, A. Praet, E.B. Bierhaus, O. Billett, A. Boggs, B. Buck, S. Carlson-Kelly, J. Cerna, K. Chaffin, E. Church, M. Coltrin, J. Daly, A. Deguzman, R. Dubisher, D. Eckart, D. Ellis, P. Falkenstern, A. Fisher, M.E. Fisher, P. Fleming, K. Fortney, S. Francis, S. Freund, S. Gonzales, P. Haas, A. Hasten, D. Hauf, A. Hilbert, D. Howell, F. Jaen, N. Jayakody, M. Jenkins, K. Johnson, M. Lefevre, H. Ma, C. Mario, K. Martin, C. May, M. McGee, B. Miller, C. Miller, G. Miller, A. Mirfakhrai, E. Muhle, C. Norman, R. Olds, C. Parish, M. Ryle, M. Schmitzer, P. Sherman, M. Skeen, M. Susak, B. Sutter, Q. Tran, C. Welch, R. Witherspoon, J. Wood, J. Zareski, M. Arvizu-Jakubicki, E. Asphaug, E. Audi, R.-L. Ballouz, R. Bandrowski, K.J. Becker, T.L. Becker, S. Bendall, C.A. Bennett, H. Bloomenthal, D. Blum, W.V. Boynton, J. Brodbeck, K.N. Burke, M. Chojnacki, A. Colpo, J. Contreras, J. Cutts, C. Y. Drouet d'Aubigny, D. Dean, D.N. DellaGiustina, B. Diallo, D. Drinnon, K. Drozd, H.L. Enos, R. Enos, C. Fellows, T. Ferro, M.R. Fisher, G. Fitzgibbon, M. Fitzgibbon, J. Forelli, T. Forrester, I. Galinsky, R. Garcia, A. Gardner, D.R. Golish, N. Habib, D. Hamara, D. Hammond, K. Hanley, K. Harshman, C.W. Hergenrother, K. Herzog, D. Hill, C. Hoekenga, S. Hooven, E.S. Howell, E. Huettner, A. Janakus, J. Jones, T.R. Kareta, J. Kidd, K. Kingsbury, S.S. Balram-Knutson, L. Koelbel, J. Kreiner, D. Lambert, D.S. Lauretta, C. Lewin, B. Lovelace, M. Loveridge, M. Lujan, C.K. Maleszewski, R. Malhotra, K. Marchese, E. McDonough, N. Mogk, V. Morrison, E. Morton, R. Munoz, J. Nelson, M.C. Nolan, J. Padilla, R. Pennington, A. Polit, N. Ramos, V. Reddy, M. Riehl, Y.H. Tang, M. Westermann, C.W.V. Wolner, D. Worden, T. Zega, Z. Zeszut, A. Bjurstrom, L. Bloomquist, C. Dickinson, E. Keates, J. Liang, V. Nifo, A. Taylor, F. Teti, M. Caplinger, H. Bowles, S. Carter, S. Dickenshied, D. Doerres, T. Fisher, W. Hagee, J. Hill, M. Miner, D. Noss, N. Piacentine, M. Smith, A. Toland, P. Wren, M. Bernacki, D. Pino Munoz, S.-i. Watanabe, S. A. Sandford, A. Aqueche, B. Ashman, M. Barker, A. Bartels, K. Berry, B. Bos, R. Burns, A. Calloway, R. Carpenter, N. Castro, R. Cosentino, J. Donaldson, J.P. Dworkin, J. Elsila Cook, C. Emr, D. Everett, D. Fennell, K. Fleshman, D. Folta, D. Gallagher, J. Garvin, K. Getzandanner, D. Glavin, S. Hull, K. Hyde, H. Ido, A. Ingegneri, N. Jones, P. Kaotira, L.F. Lim, A. Liounis, C. Lorentson, D. Lorenz, J. Lyzhoft, E.M. Mazarico, R. Mink, W. Moore, M. Moreau, S. Mullen, J. Nagy, G. Neumann, J. Nuth, D. Poland, D.C. Reuter, L. Rhoads, S. Rieger, D. Rowlands, D. Sallitt, A. Scroggins, G. Shaw, A.A. Simon, J. Swenson, P. Vasudeva, M. Wasser, R. Zellar, J. Grossman, G. Johnston, M. Morris, J. Wendel, A. Burton, L.P. Keller, L. McNamara, S. Messenger, K. Nakamura-Messenger, A. Nguyen, K. Righter, E. Queen, K. Bellamy, K. Dill, S. Gardner, M. Giuntini, B. Key, J. Kissell, D. Patterson, D. Vaughan, B. Wright, R.W. Gaskell, L. Le Corre, J.L. Molaro, E.E. Palmer, M.A. Siegler, P. Tricarico, J.R. Weirich, T. Ireland, K. Tait, P. Bland, S. Anwar, A.S. French, J.W. McMahon, D.J. Scheeres, E.R. Jawin, T.J. McCoy, S. Russell, M. Killgore, W.F. Bottke, V.E. Hamilton, H.H. Kaplan, K.J. Walsh, J.L. Bandfield, B.C. Clark, M. Chodas, M. Lambert, R.A. Masterson, M.G. Daly, J. Freemantle, J.A. Seabrook, O.S. Barnouin, K. Craft, R.T. Daly, C. Ernst, R.C. Espiritu, M. Holdridge, M. Jones, A.H. Nair, L. Nguyen, J. Peachey, M.E. Perry, J. Plescia, J.H. Roberts, R. Steele, R. Turner, J. Backer, K. Edmundson, J. Mapel, M. Milazzo, S. Sides, C. Manzoni, B. May, M. Delbo’, G. Libourel, P. Michel, A. Ryan, F. Thuillet, and B. Marty

Subjects
Geosciences (General)
Abstract

During its approach to asteroid (101955) Bennu, NASA’s Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) spacecraft surveyed Bennu’s immediate environment, photometric properties, and rotation state. Discovery of a dusty environment, a natural satellite, or unexpected asteroid characteristics would have had consequences for the mission’s safety and observation strategy. Here we show that spacecraft observations during this period were highly sensitive to satellites (sub-meter scale) but reveal none, although later navigational images indicate that further investigation is needed. We constrain average dust production in September 2018 from Bennu’s surface to an upper limit of 150 g/s averaged over 34 min. Bennu’s disk-integrated photometric phase function validates measurements from the pre-encounter astronomical campaign. We demonstrate that Bennu’s rotation rate is accelerating continuously at 3.63 ± 0.52 × 10^(–6) degrees/sq. day, likely due to the Yarkovsky–O’Keefe–Radzievskii–Paddack (YORP) effect, with evolutionary implications.

Published
2019
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4. Characterization of the carbon component in cometary Stardust samples by means of infrared and Raman spectroscopy

Author

G. M. Muñoz Caro, Emmanuel Dartois, and K. Nakamura-Messenger

Subjects
Physics, Infrared, chemistry.chemical_element, Infrared spectroscopy, Astronomy and Astrophysics, Aerogel, Astrobiology, symbols.namesake, Amorphous carbon, chemistry, Space and Planetary Science, symbols, Particle, Formation and evolution of the Solar System, Raman spectroscopy, Carbon
Abstract

Aims. We attempt to ellucidate the structure and chemical composition of the carbon bulk detected in cometary Stardust particles. We determine if the carbon material observed spectroscopically is of true cometary origin and whether or not it was formed by direct UV-photoprocessing of icy grain mantles in the local dense cloud and/or the solar nebula. Methods. We acquire infrared spectroscopy of ten Stardust cometary particles from track 35 and the aerogel inside and outside the particle track. Using infrared and Raman spectroscopy, the dominant carbon component in cometary Stardust particles was compared to IDPs and organics made from UV-photoprocessing of interstellar/circumstellar ice analogs in the laboratory. The Raman spectra of Stardust particles used in this comparison are adapted from the literature. Results. As indicated in previous works, it is found that the collecting aerogel medium, processed during particle impact, poses serious problems for the infrared analysis of the Stardust cometary particles reported in this paper. We identify the structure of the carbon bulk of the organic material retrieved from the aerogel with a form of (hydrogenated) amorphous carbon. It is found that this material is not a direct product of ice photoprocessing.

Published
2008
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5. Pebbles and sand on asteroid (162173) Ryugu: In situ observation and particles returned to Earth

Author

S. Tachibana, H. Sawada, R. Okazaki, Y. Takano, K. Sakamoto, Y. N. Miura, C. Okamoto, H. Yano, S. Yamanouchi, P. Michel, Y. Zhang, S. Schwartz, F. Thuillet, H. Yurimoto, T. Nakamura, T. Noguchi, H. Yabuta, H. Naraoka, A. Tsuchiyama, N. Imae, K. Kurosawa, A. M. Nakamura, K. Ogawa, S. Sugita, T. Morota, R. Honda, S. Kameda, E. Tatsumi, Y. Cho, K. Yoshioka, Y. Yokota, M. Hayakawa, M. Matsuoka, N. Sakatani, M. Yamada, T. Kouyama, H. Suzuki, C. Honda, T. Yoshimitsu, T. Kubota, H. Demura, T. Yada, M. Nishimura, K. Yogata, A. Nakato, M. Yoshitake, A. I. Suzuki, S. Furuya, K. Hatakeda, A. Miyazaki, K. Kumagai, T. Okada, M. Abe, T. Usui, T. R. Ireland, M. Fujimoto, T. Yamada, M. Arakawa, H. C. Connolly, A. Fujii, S. Hasegawa, N. Hirata, C. Hirose, S. Hosoda, Y. Iijima, H. Ikeda, M. Ishiguro, Y. Ishihara, T. Iwata, S. Kikuchi, K. Kitazato, D. S. Lauretta, G. Libourel, B. Marty, K. Matsumoto, T. Michikami, Y. Mimasu, A. Miura, O. Mori, K. Nakamura-Messenger, N. Namiki, A. N. Nguyen, L. R. Nittler, H. Noda, R. Noguchi, N. Ogawa, G. Ono, M. Ozaki, H. Senshu, T. Shimada, Y. Shimaki, K. Shirai, S. Soldini, T. Takahashi, Y. Takei, H. Takeuchi, R. Tsukizaki, K. Wada, Y. Yamamoto, K. Yoshikawa, K. Yumoto, M. E. Zolensky, S. Nakazawa, F. Terui, S. Tanaka, T. Saiki, M. Yoshikawa, S. Watanabe, and Y. Tsuda

Subjects
Multidisciplinary
Abstract

The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. The mission performed two landing operations to collect samples of surface and subsurface material, the latter exposed by an artificial impact. We present images of the second touchdown site, finding that ejecta from the impact crater was present at the sample location. Surface pebbles at both landing sites show morphological variations ranging from rugged to smooth, similar to Ryugu’s boulders, and shapes from quasi-spherical to flattened. The samples were returned to Earth on 6 December 2020. We describe the morphology of >5 grams of returned pebbles and sand. Their diverse color, shape, and structure are consistent with the observed materials of Ryugu; we conclude that they are a representative sample of the asteroid.

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6. OSIRIS-REx Contamination Control Strategy and Implementation.

Author

Dworkin JP, Adelman LA, Ajluni T, Andronikov AV, Aponte JC, Bartels AE, Beshore E, Bierhaus EB, Brucato JR, Bryan BH, Burton AS, Callahan MP, Castro-Wallace SL, Clark BC, Clemett SJ, Connolly HC Jr, Cutlip WE, Daly SM, Elliott VE, Elsila JE, Enos HL, Everett DF, Franchi IA, Glavin DP, Graham HV, Hendershot JE, Harris JW, Hill SL, Hildebrand AR, Jayne GO, Jenkens RW Jr, Johnson KS, Kirsch JS, Lauretta DS, Lewis AS, Loiacono JJ, Lorentson CC, Marshall JR, Martin MG, Matthias LL, McLain HL, Messenger SR, Mink RG, Moore JL, Nakamura-Messenger K, Nuth JA 3rd, Owens CV, Parish CL, Perkins BD, Pryzby MS, Reigle CA, Righter K, Rizk B, Russell JF, Sandford SA, Schepis JP, Songer J, Sovinski MF, Stahl SE, Thomas-Keprta K, Vellinga JM, and Walker MS

Abstract

OSIRIS-REx will return pristine samples of carbonaceous asteroid Bennu. This article describes how pristine was defined based on expectations of Bennu and on a realistic understanding of what is achievable with a constrained schedule and budget, and how that definition flowed to requirements and implementation. To return a pristine sample, the OSIRIS-REx spacecraft sampling hardware was maintained at level 100 A/2 and <180 ng/cm 2 of amino acids and hydrazine on the sampler head through precision cleaning, control of materials, and vigilance. Contamination is further characterized via witness material exposed to the spacecraft assembly and testing environment as well as in space. This characterization provided knowledge of the expected background and will be used in conjunction with archived spacecraft components for comparison with the samples when they are delivered to Earth for analysis. Most of all, the cleanliness of the OSIRIS-REx spacecraft was achieved through communication among scientists, engineers, managers, and technicians.

Published
2018
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7. Mineralogy and petrology of comet 81P/Wild 2 nucleus samples.

Author

Zolensky ME, Zega TJ, Yano H, Wirick S, Westphal AJ, Weisberg MK, Weber I, Warren JL, Velbel MA, Tsuchiyama A, Tsou P, Toppani A, Tomioka N, Tomeoka K, Teslich N, Taheri M, Susini J, Stroud R, Stephan T, Stadermann FJ, Snead CJ, Simon SB, Simionovici A, See TH, Robert F, Rietmeijer FJ, Rao W, Perronnet MC, Papanastassiou DA, Okudaira K, Ohsumi K, Ohnishi I, Nakamura-Messenger K, Nakamura T, Mostefaoui S, Mikouchi T, Meibom A, Matrajt G, Marcus MA, Leroux H, Lemelle L, Le L, Lanzirotti A, Langenhorst F, Krot AN, Keller LP, Kearsley AT, Joswiak D, Jacob D, Ishii H, Harvey R, Hagiya K, Grossman L, Grossman JN, Graham GA, Gounelle M, Gillet P, Genge MJ, Flynn G, Ferroir T, Fallon S, Fakra S, Ebel DS, Dai ZR, Cordier P, Clark B, Chi M, Butterworth AL, Brownlee DE, Bridges JC, Brennan S, Brearley A, Bradley JP, Bleuet P, Bland PA, and Bastien R

Abstract

The bulk of the comet 81P/Wild 2 (hereafter Wild 2) samples returned to Earth by the Stardust spacecraft appear to be weakly constructed mixtures of nanometer-scale grains, with occasional much larger (over 1 micrometer) ferromagnesian silicates, Fe-Ni sulfides, Fe-Ni metal, and accessory phases. The very wide range of olivine and low-Ca pyroxene compositions in comet Wild 2 requires a wide range of formation conditions, probably reflecting very different formation locations in the protoplanetary disk. The restricted compositional ranges of Fe-Ni sulfides, the wide range for silicates, and the absence of hydrous phases indicate that comet Wild 2 experienced little or no aqueous alteration. Less abundant Wild 2 materials include a refractory particle, whose presence appears to require radial transport in the early protoplanetary disk.

Published
2006
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8. Elemental compositions of comet 81P/Wild 2 samples collected by Stardust.

Author

Flynn GJ, Bleuet P, Borg J, Bradley JP, Brenker FE, Brennan S, Bridges J, Brownlee DE, Bullock ES, Burghammer M, Clark BC, Dai ZR, Daghlian CP, Djouadi Z, Fakra S, Ferroir T, Floss C, Franchi IA, Gainsforth Z, Gallien JP, Gillet P, Grant PG, Graham GA, Green SF, Grossemy F, Heck PR, Herzog GF, Hoppe P, Hörz F, Huth J, Ignatyev K, Ishii HA, Janssens K, Joswiak D, Kearsley AT, Khodja H, Lanzirotti A, Leitner J, Lemelle L, Leroux H, Luening K, Macpherson GJ, Marhas KK, Marcus MA, Matrajt G, Nakamura T, Nakamura-Messenger K, Nakano T, Newville M, Papanastassiou DA, Pianetta P, Rao W, Riekel C, Rietmeijer FJ, Rost D, Schwandt CS, See TH, Sheffield-Parker J, Simionovici A, Sitnitsky I, Snead CJ, Stadermann FJ, Stephan T, Stroud RM, Susini J, Suzuki Y, Sutton SR, Taylor S, Teslich N, Troadec D, Tsou P, Tsuchiyama A, Uesugi K, Vekemans B, Vicenzi EP, Vincze L, Westphal AJ, Wozniakiewicz P, Zinner E, and Zolensky ME

Abstract

We measured the elemental compositions of material from 23 particles in aerogel and from residue in seven craters in aluminum foil that was collected during passage of the Stardust spacecraft through the coma of comet 81P/Wild 2. These particles are chemically heterogeneous at the largest size scale analyzed ( approximately 180 ng). The mean elemental composition of this Wild 2 material is consistent with the CI meteorite composition, which is thought to represent the bulk composition of the solar system, for the elements Mg, Si, Mn, Fe, and Ni to 35%, and for Ca and Ti to 60%. The elements Cu, Zn, and Ga appear enriched in this Wild 2 material, which suggests that the CI meteorites may not represent the solar system composition for these moderately volatile minor elements.

Published
2006
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9. Isotopic compositions of cometary matter returned by Stardust.

Author

McKeegan KD, Aléon J, Bradley J, Brownlee D, Busemann H, Butterworth A, Chaussidon M, Fallon S, Floss C, Gilmour J, Gounelle M, Graham G, Guan Y, Heck PR, Hoppe P, Hutcheon ID, Huth J, Ishii H, Ito M, Jacobsen SB, Kearsley A, Leshin LA, Liu MC, Lyon I, Marhas K, Marty B, Matrajt G, Meibom A, Messenger S, Mostefaoui S, Mukhopadhyay S, Nakamura-Messenger K, Nittler L, Palma R, Pepin RO, Papanastassiou DA, Robert F, Schlutter D, Snead CJ, Stadermann FJ, Stroud R, Tsou P, Westphal A, Young ED, Ziegler K, Zimmermann L, and Zinner E

Subjects
Hydrogen analysis, Neon analysis, Noble Gases analysis, Spacecraft, Carbon Isotopes analysis, Deuterium analysis, Isotopes analysis, Meteoroids, Nitrogen Isotopes analysis, Oxygen Isotopes analysis
Abstract

Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Nonterrestrial nitrogen and neon isotope ratios suggest that indigenous organic matter and highly volatile materials were successfully collected. Except for a single (17)O-enriched circumstellar stardust grain, silicate and oxide minerals have oxygen isotopic compositions consistent with solar system origin. One refractory grain is (16)O-enriched, like refractory inclusions in meteorites, suggesting that Wild 2 contains material formed at high temperature in the inner solar system and transported to the Kuiper belt before comet accretion.

Published
2006
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10. Infrared spectroscopy of comet 81P/Wild 2 samples returned by Stardust.

Author

Keller LP, Bajt S, Baratta GA, Borg J, Bradley JP, Brownlee DE, Busemann H, Brucato JR, Burchell M, Colangeli L, d'Hendecourt L, Djouadi Z, Ferrini G, Flynn G, Franchi IA, Fries M, Grady MM, Graham GA, Grossemy F, Kearsley A, Matrajt G, Nakamura-Messenger K, Mennella V, Nittler L, Palumbo ME, Stadermann FJ, Tsou P, Rotundi A, Sandford SA, Snead C, Steele A, Wooden D, and Zolensky M

Subjects
Cosmic Dust analysis, Spacecraft, Spectroscopy, Fourier Transform Infrared, Hydrocarbons analysis, Meteoroids, Silicates analysis
Abstract

Infrared spectra of material captured from comet 81P/Wild 2 by the Stardust spacecraft reveal indigenous aliphatic hydrocarbons similar to those in interplanetary dust particles thought to be derived from comets, but with longer chain lengths than those observed in the diffuse interstellar medium. Similarly, the Stardust samples contain abundant amorphous silicates in addition to crystalline silicates such as olivine and pyroxene. The presence of crystalline silicates in Wild 2 is consistent with mixing of solar system and interstellar matter. No hydrous silicates or carbonate minerals were detected, which suggests a lack of aqueous processing of Wild 2 dust.

Published
2006
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11. Organic globules in the Tagish Lake meteorite: remnants of the protosolar disk.

Author

Nakamura-Messenger K, Messenger S, Keller LP, Clemett SJ, and Zolensky ME

Subjects
Carbon Isotopes analysis, Deuterium analysis, Ice, Nitrogen Isotopes analysis, Oxygen analysis, Temperature, Ultraviolet Rays, Carbon analysis, Hydrogen analysis, Meteoroids, Nitrogen analysis
Abstract

Coordinated transmission electron microscopy and isotopic measurements of organic globules in the Tagish Lake meteorite shows that they have elevated ratios of nitrogen-15 to nitrogen-14 (1.2 to 2 times terrestrial) and of deuterium to hydrogen (2.5 to 9 times terrestrial). These isotopic anomalies are indicative of mass fractionation during chemical reactions at extremely low temperatures (10 to 20 kelvin), characteristic of cold molecular clouds and the outer protosolar disk. The globules probably originated as organic ice coatings on preexisting grains that were photochemically processed into refractory organic matter. The globules resemble cometary carbon, hydrogen, oxygen, and nitrogen (CHON) particles, suggesting that such grains were important constituents of the solar system starting materials.

Published
2006
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