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SCIENCE REPORT - Leonid Meteor Shower

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This is the VOA Special English Science Report.

Sometimes in the month of November, a special event happens in the sky that observers may remember for a lifetime. The event is more than a meteor shower. It is a meteor storm.

Meteors are pieces of rock from space that burn up in our atmosphere. Meteor showers happen when the Earth passes through a large amount of space material during its orbit around the sun. However, thousands of meteors fall during a meteor storm. Some of them may briefly shine brighter than any star in the sky.

The Leonid (LEE-oh-nid) meteor shower happens every November. In most years, it is not unusual. Leonid meteors fall at an average rate of only fifteen each hour. However, every thirty-three years an object passes through our solar system that changes the Leonid meteor shower.

A comet is a large body of gas, ice and rock. Comets leave behind these materials as they orbit the sun. Each year around November Eighteenth, the Earth passes through material left behind by a comet called Tempel-Tuttle.

In February of Nineteen-Ninety-Eight, comet Tempel-Tuttle returned to the inner solar system. Astronomers have found that the Leonid meteor shower can become very active for about five years after the appearance of that comet.

Astronomers also have discovered that each appearance of comet Tempel-Tuttle leaves behind a different path of material. This discovery has permitted astronomers to know when the Leonid meteor shower may be most intense. Some astronomers believe the Leonids this month may be a meteor storm.

In Eighteen-Thirty-Three, observers in the eastern United States saw an intense meteor storm. One person estimated that meteors fell at a rate of ten-thousand an hour above West Point, New York. In Nineteen-Sixty-Six, people in the western United States saw another intense Leonid meteor storm.

This year, astronomers believe that there will be two periods of heavy meteor activity starting on November Eighteenth. At Ten Hours Universal Time, observers in North America should see a large number of meteors.

Another period of meteor activity should happen at about Eighteen Hours Universal Time. Observers in east Asia and western Australia will see it best. Astronomers who have researched the Leonids say the best chance to see a meteor storm may be this year and next year.

This VOA Special English Science Report was written by Mario Ritter.

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