s******o 发帖数: 298 | 1 April 22, 2002 | Scientific intuition tells us that a comet's nucleus should
be a frozen mountain of ice and dust. But that's not what Deep Space 1
discovered when it flew past Comet 19P/Borrelly last year. A recently released
analysis of spacecraft spectra finds that Borrelly's "icy heart" exhibits no
trace of water ice or any water-bearing minerals. Moreover, the nucleus is
actually quite hot — ranging from 300° to 345° Kelvin (80° to 160° F).
What this means, according to Laurence Soderblom ( |
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