Published July 2012
| public
Journal Article
A multi-instrument study of Comet C/2009 P1 (Garradd) at 2.1 AU (pre-perihelion) from the Sun
Abstract
We observed Comet C/2009 P1 (Garradd) on UT 2011 September 8th and 9th at a large heliocentric distance of 2.1 AU upon its entry to the inner Solar System. The observations were performed using high-resolution infrared spectrometers (NIRSPEC at Keck II and CSHELL at IRTF), allowing us to obtain strong detections of H_2O, CO, CH_4 and HCN and sensitive upper-limits for C_2H_6, C_2H_2, NH_3 and HC_3N. We oriented the slit at 45° from the projected Sun–comet vector and obtained spatial profiles of H_2O, CH_4, and HCN that revealed notable differences among these species. In particular, we observed a strong excess of water in the projected sunward direction, probably due to a solar-activated jet releasing water-rich icy grains.
Additional Information
© 2012 Elsevier Inc. Received 20 January 2012; Revised 23 March 2012; Accepted 26 March 2012; Available online 13 April 2012. G.L.V., M.J.M., M.A.D. and B.P.B. acknowledge support from NASA's Astrobiology Institute (RTOP 344-53-51), and NASA's Planetary Atmospheres and Astronomy Programs (RTOPs 344-32-07, 08-PAST08-0034, 08-PATM08-0031). BPB acknowledges support from the NSF Astronomy and Astrophysics Grants Program (AST-0807939) and LP acknowledges support from the NASA Postdoctoral Program. GAB acknowledges support from the NASA Origins of Solar Systems program. The data presented herein were obtained at the W.M. Keck Observatory operated as a scientific partnership among CalTech, UCLA, and NASA. This 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. We are most fortunate to have the opportunity to conduct observations from this mountain.Additional details
- Eprint ID
- 32993
- DOI
- 10.1016/j.icarus.2012.03.027
- Resolver ID
- CaltechAUTHORS:20120807-152139571
- RTOP 344-53-51
- NASA
- RTOP 344-32-07
- NASA
- RTOP 08-PAST08-0034
- NASA
- RTOP 08-PATM08-0031
- NASA
- AST-0807939
- NSF
- NASA Postdoctoral Program
- Created
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2012-08-07Created from EPrint's datestamp field
- Updated
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2021-11-09Created from EPrint's last_modified field
- Caltech groups
- Division of Geological and Planetary Sciences