Chemistry in cometary comae

Irvine, W. M.; Dickens, J. E.; Lovell, A. J.; Schloerb, F. P.; Senay, M.; Bergin, E. A.; Jewitt, D.; Matthews, H. E.

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NASA NTRS · 20040142175

Chemistry in cometary comae

Irvine, W. M.·Dickens, J. E.·Lovell, A. J.·Schloerb, F. P.·Senay, M.·Bergin, E. A.·Jewitt, D.·Matthews, H. E.

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Abstract

Significant gas-phase chemistry occurs in the comae of bright comets, as is demonstrated here for the case of Comet Hale-Bopp. The abundance ratio of the two isomers, hydrogen cyanide and hydrogen isocyanide, is shown to vary with heliocentric distance in a way that is consistent with production of HNC by ion-molecule chemistry initiated by the photoionization of water. Likewise, the first maps of emission from HCO+ show an abundance and an extended distribution that are consistent with the same chemical model.

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Non-NASA Center NASA Discipline Exobiology Cyanates/analysis/chemistry Hydrogen Cyanide/analysis/chemistry Meteoroids Support, Non-U.S. Gov't Chemistry, Physical Support, U.S. Gov't, Non-P.H.S Astronomy Gases

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Irvine, W. M., Dickens, J. E., Lovell, A. J., Schloerb, F. P., Senay, M., Bergin, E. A., Jewitt, D., Matthews, H. E.. 1998-01-01. Chemistry in cometary comae. https://ntrs.nasa.gov/citations/20040142175

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