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发帖数: 1994 | 1 A Perseid Aurora
Credit & Copyright: Jimmy Westlake (Colorado Mountain College)
Explanation: Just after the Moon set but before the Sun rose in the early morning hours of
2000 August 12, meteors pelted the Earth from the direction of the constellation Perseus,
while ions pelted the Earth from the Sun. The meteors were expected as sub-sand grains long
left behind by Comet Swift-Tuttle annually create the Perseids Meteor Shower. The aurorae
were unexpected, however, as electrons, protons, |
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