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An increased number of meteors all appearing to diverge from the direction of a single
point, called radiant. Meteor showers occur annually on the same dates, when the Earth
crosses through a meteoroid stream. Meteor showers are named after the constellation
in which the radiant is located. For example, the Perseids's radiant lies near the
top of the constellation Perseus. Most meteor showers are caused by comets. As a comet
orbits the Sun it sheds an icy, dusty debris stream along its orbit. When the Earth's
orbit intersects the dust trail, more meteors are seen as the cometary debris encounters
our planet's atmosphere. In the case of the Geminids and Quadrantids, those meteor
showers come from the debris scattered by orbiting asteroids. Typical meteor showers
show 15 to 100 meteors per hour at their peak. On very rare occasions, during a meteor
storm, thousands of meteors fall per hour. Prominent meteor showers are: Quadrantids,
Lyrids, Eta Aquariids, Delta Aquariids, Perseids, Orionids, Taurids, Leonids, Geminids,
Ursids, Alpha Capricornids.
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