skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Organics Captured from Comet 81P/Wild 2 by the StardustSpacecraft

Abstract

No abstract prepared.

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Publication Date:
Research Org.:
COLLABORATION - NASA-Ames ResearchCenter
OSTI Identifier:
902460
Report Number(s):
LBNL-62206
Journal ID: ISSN 0193-4511; SCEHDK; R&D Project: CB1102; BnR: KC0302030; TRN: US200717%%312
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Science; Journal Volume: 314; Related Information: Journal Publication Date: 12/15/2006
Country of Publication:
United States
Language:
English
Subject:
37; COMETS; CHEMICAL COMPOSITION; ORGANIC COMPOUNDS; SPACE VEHICLES; advanced light source als

Citation Formats

Sandford, S.A., Aleon, J., Alexander, C.M.O'D., Araki, T., Bajt,S., Baratta, G.A., Borg, J., Brucato, J.R., Burchell, M.J., Busemann, H., Butterworth, A., Clemett, S.J., Cody, G., Colangeli, L., Cooper, G., D'Hendecourt, L., Djouadi, Z., Dworkin, J.P., Ferrini, G., Fleckenstein,H., Flynn, G., Franchi, I.A., Fries, M., Gilles, M.K., Glavin, D.P., Gounelle, M., Grossemy, F., Jacobsen, C., Keller, L.P., Kilcoyne, A.L.D., Leitner, J., Matrajt, G., Meibom, A., Mennella, V., Mostefaoui, S., Nittler, L.R., Palumbo, M.E., Robert, F., Rotundi, A., Snead, C.J., Spencer, M.K., Steele, A., Stephan, T., Tyliszczak, T., Westphal, A.J., Wirick, S., Wopenka, B., Yabuta, H., Zare, R.N., and Zolensky, M.. Organics Captured from Comet 81P/Wild 2 by the StardustSpacecraft. United States: N. p., 2007. Web.
Sandford, S.A., Aleon, J., Alexander, C.M.O'D., Araki, T., Bajt,S., Baratta, G.A., Borg, J., Brucato, J.R., Burchell, M.J., Busemann, H., Butterworth, A., Clemett, S.J., Cody, G., Colangeli, L., Cooper, G., D'Hendecourt, L., Djouadi, Z., Dworkin, J.P., Ferrini, G., Fleckenstein,H., Flynn, G., Franchi, I.A., Fries, M., Gilles, M.K., Glavin, D.P., Gounelle, M., Grossemy, F., Jacobsen, C., Keller, L.P., Kilcoyne, A.L.D., Leitner, J., Matrajt, G., Meibom, A., Mennella, V., Mostefaoui, S., Nittler, L.R., Palumbo, M.E., Robert, F., Rotundi, A., Snead, C.J., Spencer, M.K., Steele, A., Stephan, T., Tyliszczak, T., Westphal, A.J., Wirick, S., Wopenka, B., Yabuta, H., Zare, R.N., & Zolensky, M.. Organics Captured from Comet 81P/Wild 2 by the StardustSpacecraft. United States.
Sandford, S.A., Aleon, J., Alexander, C.M.O'D., Araki, T., Bajt,S., Baratta, G.A., Borg, J., Brucato, J.R., Burchell, M.J., Busemann, H., Butterworth, A., Clemett, S.J., Cody, G., Colangeli, L., Cooper, G., D'Hendecourt, L., Djouadi, Z., Dworkin, J.P., Ferrini, G., Fleckenstein,H., Flynn, G., Franchi, I.A., Fries, M., Gilles, M.K., Glavin, D.P., Gounelle, M., Grossemy, F., Jacobsen, C., Keller, L.P., Kilcoyne, A.L.D., Leitner, J., Matrajt, G., Meibom, A., Mennella, V., Mostefaoui, S., Nittler, L.R., Palumbo, M.E., Robert, F., Rotundi, A., Snead, C.J., Spencer, M.K., Steele, A., Stephan, T., Tyliszczak, T., Westphal, A.J., Wirick, S., Wopenka, B., Yabuta, H., Zare, R.N., and Zolensky, M.. Thu . "Organics Captured from Comet 81P/Wild 2 by the StardustSpacecraft". United States. doi:.
@article{osti_902460,
title = {Organics Captured from Comet 81P/Wild 2 by the StardustSpacecraft},
author = {Sandford, S.A. and Aleon, J. and Alexander, C.M.O'D. and Araki, T. and Bajt,S. and Baratta, G.A. and Borg, J. and Brucato, J.R. and Burchell, M.J. and Busemann, H. and Butterworth, A. and Clemett, S.J. and Cody, G. and Colangeli, L. and Cooper, G. and D'Hendecourt, L. and Djouadi, Z. and Dworkin, J.P. and Ferrini, G. and Fleckenstein,H. and Flynn, G. and Franchi, I.A. and Fries, M. and Gilles, M.K. and Glavin, D.P. and Gounelle, M. and Grossemy, F. and Jacobsen, C. and Keller, L.P. and Kilcoyne, A.L.D. and Leitner, J. and Matrajt, G. and Meibom, A. and Mennella, V. and Mostefaoui, S. and Nittler, L.R. and Palumbo, M.E. and Robert, F. and Rotundi, A. and Snead, C.J. and Spencer, M.K. and Steele, A. and Stephan, T. and Tyliszczak, T. and Westphal, A.J. and Wirick, S. and Wopenka, B. and Yabuta, H. and Zare, R.N. and Zolensky, M.},
abstractNote = {No abstract prepared.},
doi = {},
journal = {Science},
number = ,
volume = 314,
place = {United States},
year = {Thu Jan 04 00:00:00 EST 2007},
month = {Thu Jan 04 00:00:00 EST 2007}
}
  • We studied three Stardust fragments with infrared spectroscopy to characterize organic matter; with synchrotron-induced X-ray fluorescence to determine Fe contents and certain elemental ratios to iron; with scanning electron microscopy (SEM) to image sample morphology and to detect semiquantitatively Mg, Al, Si, Ca, and Fe; and with nuclear reaction analysis (NRA) to measure C, N, O, and Si. A fourth fragment was analyzed by SEM only. Fragment C2054,0,35,21 from track 35 (hereafter C21) is extremely rich in C and contains appreciable concentrations of Mg, Al, and Ca, but little Fe. Fragments C2054,0,35,23 (C23), C2044,0,41 (C41), and C2054,0,35,51,0 (C51), from tracksmore » 35, 41, and 35, respectively, consist largely but not exclusively of aerogel. C23 contains Mg and finely dispersed S, but little Al, Ca or Fe. Pooled CI-normalized elemental ratios for C21, C23, and C41 are as follows: Ti/Fe, 5.0; Cr/Fe, 0.84; Mn/Fe, 0.97; Ni/Fe, 2.4; and Zn/Fe, 31. The enrichments in Ti and Zn may be related to the presence of aerogel. Minimum weight percentages of C and N estimated without correcting for the presence of aerogel are 30 and 0.7 for C21; 2.8 and 0.2 for C23; 1.2 and 0.14 for C41. After corrections for the presence of aerogel containing 1.4 wt% C and 0.02 wt% N, the corresponding results are 37 and 0.85 for C21; and 10 and 1 for C23; and {approx}1 and {approx}1, for C41 (The results for C41 have large uncertainties). These weight percentages are larger than or comparable to values for carbonaceous meteorites. C/N atomic ratios without/without aerogel corrections are 51/51 for C21, 17/11 for C23, and 10/{approx}1 for C41. Within the uncertainties these values are within the range for carbonaceous meteorites.« less
  • Nanoglobules are a form of organic matter found in interplanetary dust particles and primitive meteorites and are commonly associated with {sup 15}N and D isotopic anomalies that are suggestive of interstellar processes. We report the discovery of two isotopically-anomalous organic globules from the Stardust collection of particles from Comet 81P/Wild 2 and compare them with nanoglobules from the Murchison CM2 meteorite. One globule from Stardust Cometary Track 80 contains highly aromatic organic matter and a large {sup 15}N anomaly ({delta}{sup 15}N = 1120{per_thousand}). Associated, non-globular, organic matter from this track is less enriched in {sup 15}N and contains a mixturemore » of aromatic and oxidized carbon similar to bulk insoluble organic material (IOM) from primitive meteorites. The second globule, from Cometary Track 2, contains non-aromatic organic matter with abundant nitrile ({single_bond}C{triple_bond}N) and carboxyl ({single_bond}COOH) functional groups. It is significantly enriched in D ({delta}D = 1000{per_thousand}) but has a terrestrial {sup 15}N/{sup 14}N ratio. Experiments indicate that similar D enrichments, unaccompanied by {sup 15}N fractionation, can be reproduced in the laboratory by electron irradiation of epoxy or cyanoacrylate. Thus, a terrestrial origin for this globule cannot be ruled out, and, conversely, exposure to high-energy electron irradiation in space may be an important factor in producing D anomalies in organic materials. For comparison, we report two Murchison globules: one with a large {sup 15}N enrichment and highly aromatic chemistry analogous to the Track 80 globule and the other only moderately enriched in {sup 15}N with IOM-like chemistry. The observation of organic globules in Comet 81P/Wild 2 indicates that comets likely sampled the same reservoirs of organic matter as did the chondrite parent bodies. The observed isotopic anomalies in the globules are most likely preserved signatures of low temperature (<10 K) chemistry in the interstellar medium or perhaps the outer regions of the solar nebula. In other extraterrestrial samples, D isotopic anomalies, but not those of {sup 15}N, may be explained in part by exposure to ionizing electron radiation.« less
  • Organics found in Comet Wild 2 samples show a heterogeneous and unequilibrated distribution in abundance and composition. Some organics are similar, but not identical, to those in interplanetary dust particles (IDPs) and carbonaceous meteorites. A class of aromatic-poor organic material is also present. The organics are rich in O and N compared to meteoritic organics. Aromatic compounds are present, but the samples tend to be relatively poorer in aromatics than meteorites and IDPs. D and {sup 15}N suggest that some organics have an interstellar/protostellar heritage. While the variable extent of modification of these materials by impact capture is not yetmore » fully constrained, a remarkably diverse suite of organic compounds is present and identifiable within the returned samples. Comets are small bodies that accreted in the outer Solar System during its formation (1) and thus may consist of preserved samples of the ''starting materials'' from which the Solar System was made. Organic materials are expected to be present in cometary samples (2) and may include molecules made and/or modified in stellar outflows, the interstellar medium, and the protosolar nebula, as well as by parent body processing within the comet. The presence of organic compounds in comets and their ejecta is of astrobiological interest since their delivery to the early Earth may have played an important role in the origin of life on Earth (3). An overview of the Stardust Mission and the collection and recovery of Wild 2 samples is provided elsewhere (4,5). We describe the results obtained from the returned samples by the Stardust Organics Preliminary Examination Team (PET). Samples were studied using a wide range of analytical techniques, including two-step laser desorption laser ionization mass spectrometry (L{sub 2}MS), Liquid Chromatography with UV Fluorescence Detection and Time of Flight Mass Spectrometry (LC-FD/TOF-MS), Scanning Transmission X-ray Microscopy (STXM), X-ray Absorption Near Edge Spectroscopy (XANES), infrared and Raman spectroscopy, Ion Chromatography with conductivity detection (IC), Secondary Ion Mass Spectrometry (SIMS), and Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) (6). These techniques provide a wealth of information about the chemical nature and relative abundance of the organics in the samples. Our results are compared to organic materials found in primitive meteorites and interplanetary dust particles (IDPs) collected in the stratosphere, well as to astronomical and spacecraft observations of comets. Despite some uncertainties associated with the presence of contaminants and alteration of the samples during the capture process, considerable information about the nature of the organics in the samples can be determined.« less