Photograph courtesy MPAe/Linda/ESA
Published October 20, 2011
Most sky-watchers may have missed the Draconid meteor shower earlier this month due to poor viewing conditions. But the consolation prize might be the Orionids, another October meteor shower, due to peak this weekend.
Although not as showy as the August Perseids, for example, the rather modest Orionids do have a claim to fame: They're the product of Halley’s comet.
"Despite not being the most spectacular meteor shower, the Orionids have the most well known of all the meteor stream parent bodies," said Michael Solontoi, an astronomer at the Adler Planetarium in Chicago.
"As Halley's comet orbits the sun, it has left behind dust that was liberated from the comet when it was warmed by its close passage to the sun, most recently in 1986," Solontoi said. (Find out why Halley's comet has been hailed as an omen of doom.)
"The Orionid meteor shower we see is the result of the Earth passing through this trail of debris deposited by the comet."
The Orionids appear around the same time each year, when sand grain-size pebbles from Halley's debris stream race through the sky at speeds of more than 90,000 miles (145,000 kilometers) an hour.
At these high speeds, the pebbles disintegrate in Earth's upper atmosphere, creating streaks of light.
Betelgeuse: Meteor Shower Guidepost
Like other meteor showers, the Orionid shower is named after the constellation from which the meteors appears to radiate.
In this case, observers can trace the meteors back to the mythical hunter Orion, from a spot just above its bright orange star Betelgeuse.
"They really travel through the whole sky, but a nice, clear viewing of the half of the sky dominated by Orion would more than likely maximize your viewing probability," Solontoi said.
The predicted peak activity calls for about a dozen to two dozen meteors an hour, "but be aware that the fainter ones this year will potentially be drowned out by the light of a waning crescent moon," he added.
Because the constellation Orion is on the celestial equator, the cosmic fireworks should be visible around the globe, with the best viewing times after local midnight into the predawn hours of Friday and Saturday mornings, Solontoi added.
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