The Discovery of Argon in Comet C / 1995 O 1 ( Hale - Bopp
نویسنده
چکیده
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 tele-scope/spectrometer. The spectra reveal the presence H Ly β, 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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