The Search for the Diffuse Interstellar Bands and Other Molecules in Comets 17P (Holmes) and C/2007 W1 (Boattini) (original) (raw)
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Asteroids, Comets, Meteors 1993, 1994
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The Astrophysical Journal, 1998
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Molecules in Comets: An ISM-Solar System Connection?
Symposium - International Astronomical Union, 2000
Our knowledge of the volatile composition of comets has advanced considerably since the last IAU Astrochemistry Symposium, in large part due to the apparition of comet Hale-Bopp and its study with both new ground-based instruments and from spacecraft. Some 23 or 24 coma molecules are now known which are probably, at least in part, volatile constituents of the nucleus. Relative abundances have been measured for rarer isotopomers of molecules containing 13C, 15N, 34S, and D, and significant isotopic fractionation is observed for D-containing species. There are striking similarities in both relative abundances of molecular constituents and in isotopic fractionation between material in dense interstellar clouds and that in cometary comae. Whether this indicates that cometary nuclei consist of relatively unprocessed interstellar matter is less clear, since the observed coma composition is not simply related to the nuclear composition, and since recent chemical models of the outer solar n...
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We present the results of millimetre-wave spectroscopic observations and spectral surveys of the following short-period comets: 21P/Giacobini-Zinner in September 2018, 41P/Tuttle-Giacobini-Kresák in April 2017, and 64P/Swift-Gehrels and 38P/Stephan-Oterma in December 2018, carried out with the Institut de RadioAstronomie Millimétrique (IRAM) 30-m radio telescope at wavelengths between 1 and 3 mm. Comet 21P was also observed in November 1998 with the IRAM 30-m,James Clerk MaxwellTelescope, and the Caltech submillimeter Observatory radio telescopes at wavelengths from 0.8 to 3 mm. The abundances of the following molecules have been determined in those comets: HCN, CH3OH, CS, H2CO, CH3CN, and H2S in comet 21P; HCN and CH3OH in 41P; HCN, CH3OH, and CS in 64P; and CH3OH in 38P. The last three comets, classified as carbon-chain typical from visible spectro-photometry, are relatively rich in methanol (3.5–5% relative to water). On the other hand, comet 21P, classified as carbon-chain deple...
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