s******o 发帖数: 298 | 1 By Robert Roy Britt
Senior Science Writer
posted: 09:04 am ET, 05 April 2002
A systematic survey of the asteroid belt done in infrared wavelengths
indicates that there could be two or three times more large asteroids, those
more than 1 kilometer (0.6 miles) in diameter, than had been thought.
Based on observations of portions of the main asteroid belt, between Mars and
Jupiter, the new study estimates there are between 1.1 million and 1.9
million of these large space rocks. Many millions or perh |
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