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发帖数: 421 | 1 meteor shower, increase in the number of meteors observed in a
particular part of the sky. Meteor showers usually occur annually
and with varying intensity. The meteors of a meteor shower all
appear to originate at a single point in the sky known as the
radiant point, or radiant. A shower is named for the constellation
in which its radiant is located, e.g., the Lyrids appear to come
from a point in Lyra, the Perseids from Perseus, and the Orionids
from Orion. While the average counting rate of m |
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