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Conducting Miller-Urey Experiments
Published on: January 21, 2014
Chemistry in cometary comae
W M Irvine1, J E Dickens, A J Lovell
1Five College Radio Astronomy Observatory, University of Massachusetts, Amherst 01003, USA.
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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