Meteor Shower to Peak This Weekend—Fireballs Expected
Taurid shower, born of monster comet, split into two sky shows.
A meteor streaks through the night sky above Yellowstone National Park on Halloween 2008.
Photograph by Jeffrey Berkes, My Shot
Published November 4, 2011
The Taurid meteor shower is set to peak tomorrow night, and while the sky show isn't known for producing a flurry of shooting stars, it does offer a higher than normal chance of spotting bright fireballs.
Like most other meteor showers, the Taurids happen when Earth slams into a cloud of debris left behind by a passing comet.
But "this stream of cometary debris that produces the Taurids contains a large fraction of pebble-sized material in addition to the dust grain-size particles that make up most of the meteors we see enter Earth's atmosphere," said Michael Solontoi, an astronomer with the Adler Planetarium in Chicago.
When these larger bits of debris enter our atmosphere, they can produce spectacular fireballs. (Related: "'Major,' Green Meteor Lights Midwest Night Sky.")
Eyewitness reports describe fireball meteors as being brighter than any visible star or planet and even the full moon. Fireballs tend to trek across the sky at a noticeably slower pace and leave behind visible smoke trails that can last for minutes.
Meteor Shower Split in Two
Sky-watchers in the Northern Hemisphere can look for Taurid fireballs in the eastern sky, where the streaks will appear to radiate from the showers' namesake constellation: Taurus, the Bull.
What makes the Taurids even more unusual is that their source material appears to be divided into two separate clouds, resulting in back-to-back showers peaking within a week of each other and appearing to come from slightly different points within the constellation.
The Southern Taurids will peak on November 5, while the Northern Taurids will reach peak rates on November 12.
"For the Southern Taurids, one's best bet would be to observe just after midnight on Saturday, November 5, and Sunday, November 6," Solontoi said.
The Southern Taurids are expected to produce as many as 10 to 15 meteors an hour during the local predawn hours. (See related pictures of the August Perseids.)
"For the Northern Taurids," Solontoi said, "the moon is going to make all but the brightest meteors very hard to see this year, due to the fact that the moon will be in the constellation of Taurus at peak time."
Taurids Come From Broken Giant?
The Taurids have also piqued scientific interest, because both the meteor stream and the parent comet may be the remnants of a much larger comet that broke up thousands of years ago.
(Related: "New Meteor Shower Discovered; May Uncover New Comet.")
The meteor shower is thought to be produced by debris from comet Encke, which loops around the sun once every three years or so—the shortest orbit of any known comet.
According to a theory proposed in 1992 by a British astronomer, a monster comet more than 62 miles (100 kilometers) wide was broken apart some 20,000 years ago after multiple trips around the sun.
"Such a breakup could explain the larger fragments—both comet Encke itself and a number of near-Earth asteroids associated with the orbit of the Taurids—not to mention the larger concentration of pebble-sized material that produces the characteristic fireballs," Solontoi said.
"This potential connection is a great example of how studies of comets, asteroids, and meteor showers help us to piece together past events in our solar system."
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