Comet Dust Showers World with Light
12 Nov 2001
(Source: University of Western Ontario)
Department of Communications and Public Affairs
University of Western Ontario
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Thousands of falling stars will brighten the night sky this month as Earth passes through debris from a comet that crossed our solar system more than three years ago.
The Leonid meteor shower, named for the constellation Leo from which they appear to radiate, happens every year on or about November 17. Researchers at The University of Western Ontario will watch the annual display from all corners of the globe as part of their continuing studies on meteor phenomena.
Since 1997, the Meteor Physics Group at Western has studied the Leonids to develop accurate forecasts of meteor shower severity and timing. Using real-time reporting, the team has provided forecasts of the shower's activities to satellite operators around the world during the peak night, including NASA, the European Space Agency, the Canadian Department of National Defense, and the United States Space Command.
This year, the Western researchers are hoping to identify which of the various forecasting models are best at predicting the intensity of the Leonid storms.
"The models get better every year," says Peter Brown, a professor in the Department of Physics and Astronomy at Western, and manager of the Leonids project. "When we first began our work, we had no idea when the showers would happen or how severe they would be. Now we have established the timing, but we still want to be able to predict the number of meteors that will fall each hour."
The shower occurs because Earth is hurtling through a path of dust particles left by the comet Tempel-Tuttle, which last passed through the inner solar system in 1998. The particles, or meteoroids, move so quickly they can puncture solar panels, smash mirrors and short-out electronics on any of the more than 500 satellites in orbit around the planet.
The Western team, as part of a contract with NASA, will observe this year's shower from sites in Mongolia, Guam, Hawaii, New Mexico, Florida and Alabama. The shower will be recorded from each location with high sensitivity video cameras the team developed. A meteor radar system unique to Western will also record the event from campus.
"The cameras are much like security cameras, but just very sensitive to light," says Margaret Campbell, a PhD student in the Department of Physics and Astronomy and an expert in application of video technology to meteor observations. "The information we get from them is critical to agencies like NASA because of the significant risk to spacecraft and satellites during the meteor shower. We'll capture the event, improve our models with the new data and that will give satellite operators a better idea of what could happen next year."
In addition to Western's model, other predictions have been made for the shower by research teams in the United Kingdom and Finland. Many of the models predict a severe shower this year, with up to 10,000 meteors falling per hour, says Brown.
"Unlike some academic models, the meteor forecasts have a truth test attached to it. We actually made a public statement of our predictions this year by publishing them in a peer reviewed journal, so now we'll have some fun with our colleagues finding out who is right."
The Leonids meteor shower should be visible from Southern Ontario this year under dark, clear skies on the night of Saturday, November 17 and the morning of Sunday, November 18.
Peter Brown and Margaret Campbell can be reached at the Los Alamos National Laboratory in New Mexico at (505) 665-7134 until Friday, November 16. On November 17 and 18, they can be reached at the Apache Point Observatory at (505) 437-6822. Peter Jedicke, spokesperson for the Western Leonid project and Honorary President of the London Centre of the Royal Astronomical Society of Canada, can be reached at (519) 474-5899.