Meteor Showers

• With each pass by the Sun, some of the comet's ice melts and it sheds a large amount of debris. The debris left behind can produce a meteor shower when the Earth runs into the orbit of the comet, even after the comet has completely disintegrated.
• The direction from which the shower appears to originate is known as a radiant. The radiant is typically assigned a constellation and the name of the shower is related to that constellation. The Perseids, for example, are meteors which appear to come from a point within the constellation of Perseus.
• Most meteor showers produce only a few meteors per hour, rarely producing as many as one meteor every 30 seconds.
• The most visible meteor shower in most years is the Perseids, which peaks on August 12th of each year at over 1 meteor per minute.
• A particularly active meteor shower is knows as a meteor storm.
  • Perhaps the most spectacular meteor storm is the Leonids, the King of Meteor Showers, which has produced hundreds of thousands of meteors per hour. The Leonid storm of 1833 was particularly impressive, as shown in this engraving.
  • The Leonids typically produces a "meteor storm" approximately every 33 years, with hundreds of thousands of meteors per hour. The last two massive Leonid storms were in 1933 and 1966. The anticipated storm of 1999 was much less spectacular. When the Leonid shower is not storming it is less active than the Perseids.
• The Earth runs into more meteors on the side facing the direction of the Earth’s orbital motion (just as more snow hits the front windshield while the car is moving), so the predawn sky is the best place to watch for meteors. This animation (QuickTime movie of the Leonids) might help with the visualization.

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