Infrared Observations of Methanol in Comet P/Swift-Tuttle

✍ Scribed by Susan Hoban; Dennis C. Reuter; Michael A. DiSanti; Michael J. Mumma; Richard Elston

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 473 KB
• Volume: 105
• Category: Article
• ISSN: 0019-1035
• DOI: 10.1006/icar.1993.1148

✦ Synopsis

We present infrared spectroscopic observations of Comet (\mathrm{P} /) Swift-Tuttle obtained with the Cryogenic Spectrometer at Kitt Peak on 1992 November 8, 9, and 12 and December 8 and 10. The spectra cover the 2.9-3.6- (\mu \mathrm{m}) region. We detect emission from the (\nu_{3}) band of cometary methanol at (3.52 \mu \mathrm{m}) in all of our spectra. During this time, the production rate of methanol was (Q_{\mathrm{CH}{3} \mathrm{OH}}=) 2-6 (\times 10^{28} \mathrm{sec}^{-1}), with weak evidence for short-term temporal variability in (Q{\mathrm{CH}{3} \mathrm{OH}}). We find the weighted average for the relative abundance of methanol with respect to water to be (7 \pm 1 %), which supports the notion that methanol constitutes a significant fraction of the volatile carbon in comets. Our spectra of Comet (p /) Swift-Tuttle indicate that the (\nu{2}) and (\nu_{9}) bands of methanol comprise approximately (60 %) of the "cometary organic feature" centered near (3.4 \mu \mathrm{m}). Formaldehyde was not detected in these spectra; upper limits are presented. O 1993 Academic Press, Inc.