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发帖数: 1994 | 1 http://sciencenow.sciencemag.org/cgi/content/full/2002/1126/1
Life Safe From Supernovas?
Space is full of threats to life, especially asteroids that smack into Earth. An even more explosive
hazard looms in deep space: supernovas, which can unleash enough radiation to zap our
life-shielding ozone layer. However, a new study, accepted for publication in the Astrophysical
Journal, concludes that a supernova must blow up within 25 light-years of Earth to w |
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