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发帖数: 298 | 1 By Robert Roy Britt
Senior Science Writer
posted: 07:00 am ET
26 March 2002
In the past six months, while the world focused on the continuing threat of
global terrorism, as many as a dozen or more asteroids sneaked up on the
Earth and zoomed by at distances just beyond the Moon's orbit and closer.
Most were never noticed. Earlier this month, astronomers did spot one. Four
days after it flew by.
In discussing these events, experts describe a planet vulnerable to an
unexpected attack that could, i |
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