2007 Orionid Meteor Shower

It’s the time of year for the Orionid meteor shower. The best viewing time is the morning of October 21st and the rate should be about 10-15 per hour. Not as impressive as the Perseid Meteor shower earlier this year, but it will still be cool to see.

The moon will be in a gibbous phase which is more than half, but less than full; however, it does set around 1AM, so that should provide about four hours of good observing time (also dependant on cloud cover).

The radiant point or origin of the meteors will be located in the eastern sky between Betelgeuse and Mars. See illustration below.

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From the Astronomy Magazine Newsletter

This year’s annual Orionid Meteor shower occurs 5 days before Full Moon. But the bright Moon sets by 2 A.M., so early-morning observers should be sure to catch the shower this month.

The Orionids appear to radiate from a spot in northeastern Orion near its border with Gemini. The radiant rises before midnight and stands high in the south by 4 A.M., a full 2 hours before dawn. The shower began October 2 and ends November 7.

Meteor rates start and end with a trickle, but they achieve a substantial peak October 21. In 1993 and 1998, the Orionids displayed enhanced rates 3 to 4 days before the usual peak, so it’s worth watching the shower over a week’s time centered on the date of maximum. Rates can reach 20 meteors per hour, and occasionally more.

The predawn hours offer the best viewing. These meteors are among the fastest of all shower meteors, striking Earth’s upper atmosphere at 41 miles per second. Many leave persistent trains – glowing tubes of ionized gas created as the incoming dust particles burn up.

Orionid meteors derive from debris left behind by Comet 1P/Halley during its many passages through the inner solar system. Earth’s orbit intersects this debris trail in two places. One spot gives rise to this fine autumn shower. The other location is the source of May’s Eta Aquarid shower.

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Related Links
The Orionid Meteor Shower
2007 Meteor Showers and Viewing Tips
Remains of Halley’s Comet to Rain Down Sunday Morning

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