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Meteor Showers

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Geminid Meteor Shower of 2012.

©iStockphoto.com/Clint Spencer

Several times a year, one can see hundreds of shooting stars lighting up clear, night skies. Literally celestial debris, these shooting stars are created by small - generally no more than a few centimeters in size, and no more than 0.035 to 0.070 ounces (1 to 2 grams) - space particles that do not reach the surface of the Earth. These particles, also known as meteoroids, generally belong to comets.

Meteoroid, Meteor, Meteorite and Meteor shower

Whenever a meteoroid enters the atmosphere of the Earth, it generates a flash of light called a meteor. High temperatures caused by friction between the meteoroid and gases in the Earth’s atmosphere heats the meteoroid to the point where it starts glowing. It is this glow that makes the meteoroid visible from the surface of the Earth.

Meteoroids generally glow for a very short period of time - they tend to burn up before hitting the surface of the Earth. If a meteoroid does not disintegrate while passing through Earth’s atmosphere, and hits the Earth’s surface, it is known as a Meteorite. Meteorites are thought to originate from the asteroid belt, though some meteorite debris have been identified as belonging to the Moon and Mars.

Sometimes, meteors occur in clusters known as meteor shower. Meteor showers occur when a comet comes close to the sun and produces debris - meteoroids - that spread around the comet’s orbit. Anytime the Earth’s and the comets orbit coincide, the Earth experiences a meteor shower.

Since meteoroids that create a meteor shower all move on a parallel path, and at the same velocity, they seem to originate from a single point in the sky to observers on Earth. This point is known as the radiant. By convention, meteor showers, especially the regular ones are named after the constellation that the radiant lies in.

Prominent Meteor showers

While meteors can occur at any time of the year, some meteor showers occur at the same time every year. Some of the more famous meteor showers have been observed by humans for hundreds and thousands of years.

How to view

Meteors are best viewed during the night, though meteoroids can enter the Earth’s atmosphere at any time of the day. They are just harder to see in the day light. Any ambient light, even from the moon, is a bane for meteor watchers. Meteors can be best seen away from city lights, on a new moon day.

Since meteors seem to come from the constellation they are named after, meteor watchers should try and find the direction of the constellation in the sky and look there for meteors.

July and August are some of the best months to observe meteor showers. Along with the Perseid, these months experience several minor meteor showers. December is another good month for meteor watchers.


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