TY - JOUR
T1 - The organic composition of Comet C/2001 A2 (LINEAR). I. Evidence for an unusual organic chemistry
AU - Magee-Sauer, Karen
AU - Mumma, Michael J.
AU - DiSanti, Michael A.
AU - Dello Russo, Neil
AU - Gibb, Erika L.
AU - Bonev, Boncho P.
AU - Villanueva, G. L.
N1 - Funding Information:
K.M.-S. acknowledges support from the National Science Foundation RUI Program No. 0098411 and 0407052 and the College of Liberal Arts and Sciences at Rowan University. This work was supported by the NASA Planetary Astronomy Program (RTOP 344-32-07) to M.J.M., (RTOP 344-32-98) to M.A.D., and the NASA Planetary Atmosphere Program (NAG5-12285, NNG05GA64G) to N.D.R. and (RTOP 344-33-55) to M.A.D. E.L.G. was supported under the NRC's Resident Research Associate Program at NASA's Goddard Space Flight Center. We thank the NASA TAC for awarding time to this TOO investigation. Data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community.
PY - 2008/3
Y1 - 2008/3
N2 - We used the NIRSPEC instrument on the Keck-2 telescope atop Mauna Kea, HI to observe Comet C/2001 A2 (LINEAR) in a Target of Opportunity campaign on UT 2001 July 9.5, 10.5 August 4.4, 10.5. We measured seven organic parent volatiles (C2H6, C2H2, HCN, CH4, CO, CH3OH, H2CO) simultaneously with H2O. We obtained absolute production rates and relative abundances for parent volatiles, and also measured rotational temperatures for several of these species. The chemical composition of C/2001 A2 differs substantially from any comet we have observed to date. The abundances we measure (relative to H2O) for C2H6, C2H2, HCN, and CH3OH are enriched by a factor of ∼2 to 3 in C/2001 A2 compared with most comets in our database. Other molecular species were detected within the typical range of measured abundances. C/2001 A2 presented a unique opportunity to study the chemistry of a fragmenting comet where pristine areas are exposed to the Sun.
AB - We used the NIRSPEC instrument on the Keck-2 telescope atop Mauna Kea, HI to observe Comet C/2001 A2 (LINEAR) in a Target of Opportunity campaign on UT 2001 July 9.5, 10.5 August 4.4, 10.5. We measured seven organic parent volatiles (C2H6, C2H2, HCN, CH4, CO, CH3OH, H2CO) simultaneously with H2O. We obtained absolute production rates and relative abundances for parent volatiles, and also measured rotational temperatures for several of these species. The chemical composition of C/2001 A2 differs substantially from any comet we have observed to date. The abundances we measure (relative to H2O) for C2H6, C2H2, HCN, and CH3OH are enriched by a factor of ∼2 to 3 in C/2001 A2 compared with most comets in our database. Other molecular species were detected within the typical range of measured abundances. C/2001 A2 presented a unique opportunity to study the chemistry of a fragmenting comet where pristine areas are exposed to the Sun.
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U2 - 10.1016/j.icarus.2007.10.006
DO - 10.1016/j.icarus.2007.10.006
M3 - Article
AN - SCOPUS:38949150027
SN - 0019-1035
VL - 194
SP - 347
EP - 356
JO - Icarus
JF - Icarus
IS - 1
ER -