Orionid Meteor Shower Starts Peaking Tonight

Time Lapse Footage of 2009 Orionid Meteors

Stargazers in both the Northern and Southern hemispheres could be treated to a lovely light show over the coming nights as the 2011 Orionid meteor shower enters its most active phase.

The Orionids are one of two streams of debris left behind by Halley’s comet, the other being the Eta Aquarids every May.

This year, although a sliver of moon remains in the late night sky, it will be sufficiently dark to get a good look if there is low cloud cover, especially if you are in a rural area, away from artificial lighting.

At their maximum, the Orionids produce around 10 to 20 meteors per hour, beginning before local midnight on Oct. 20 until about two hours before local dawn on Oct. 21 when Orion is highest toward the south.

These meteors are the second fastest after the November Leonids, hitting our atmosphere at 148,000 miles per hour (66 kilometers per second), according to Don Yeomans at NASA’s Jet Propulsion Laboratory in California.

Due to their entry velocity, the Orionids can produce yellow and green colors with glowing trails that may last for several seconds through to several minutes, along with the occasional fireball.

Halley’s comet visits our inner solar system every 76 years, shedding particles along the way. During its last flyby in 1986, the sun evaporated about six meters of dust-laden ice from the nucleus.

The particles typically range in size from specks of dust to grains of sand. It is unknown how long it takes for a piece of Halley’s dust to enter an Earth-crossing orbit, possibly hundreds or even thousands of years.