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The Discovery of Argon in Comet C/1995 O1 (Hale-Bopp)

S. A. Stern·D. C. Slater·M. C. Festou·J. Wm. Parker·G. R. Gladstone. M. F. A'Hearn·E. Wilkinson
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Abstract

On 30.14 March 1997 we observed the EUV spectrum of the bright comet C/1995 O1 (Hale-Bopp) at the time of its perihelion, using our EUVS sounding rocket telescope/spectrometer. The spectra reveal the presence H Ly beta, O+, and, most notably, Argon. Modelling of the retrieved Ar production rates indicates that comet Hale-Bopp is enriched in Ar relative to cosmogonic expectations. This in turn indicates that Hale-Bopp's deep interior has never been exposed to the 35-40 K temperatures necessary to deplete the comet's primordial argon supply.

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S. A. Stern, D. C. Slater, M. C. Festou, J. Wm. Parker, G. R. Gladstone. M. F. A'Hearn, E. Wilkinson. 2000-11-16. The Discovery of Argon in Comet C/1995 O1 (Hale-Bopp). https://doi.org/10.1086/317312

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