Published: July 27, 2004

Editors: Doug Duncan is available for interviews. For visuals, Fiske Planetarium has a large meteorite on display and Duncan also has a portable, baseball-sized meteorite. Call Duncan at (303) 492-5003 or Mike Liguori at (303) 492-3117 to arrange an interview.

University of Colorado at Boulder astrophysicist Doug Duncan says this year's annual Perseid meteor shower and its natural nighttime light show will be particularly good as the display becomes visible over Colorado Aug. 10-13.

"The moon will be nearly new, so it's an especially good time to see the meteor shower," said Duncan, director of CU-Boulder's astronomical laboratories including Fiske Planetarium and Sommers Bausch Observatory.

"A dark sky makes a big difference. If you're watching from Denver, you might see a couple of meteors per hour. From Boulder you might see 10 to 15 per hour. In the mountains, where the sky is really dark, you could see 60 per hour," Duncan said. The peak of the shower will come during the early morning hours of Aug. 12.

Meteor showers occur when the Earth crosses the path of a comet, sweeping through debris left behind along the orbit. Millions of chunks of ice and dust make up the tail of a comet. These chunks of debris might be as small as a pea and travel through the solar system at more than 36,000 miles per hour.

The Perseid meteor shower is caused by the Earth passing through the tail of

Comet Swift-Tuttle, which is in orbit around the sun. The chunks of space junk that make up the tail are only seen as meteors when they get caught in Earth's gravity and burn up in the atmosphere. The Perseid meteor shower is named for the Perseus constellation from which the meteors, or shooting stars, appear to radiate.

Considerably more Perseid meteors will be visible after midnight each night. Duncan, a former National Public Radio science commentator, used an analogy to explain why there aren't as many meteors before midnight.

"Think of the meteors as bugs, and the sky as the windshield of a car. After midnight, our night sky will be facing 'forward,' in the same direction as the Earth orbits around the sun. As a result, after midnight we see a lot more 'bugs' hitting our 'windshield.'"

Duncan has appeared on BBC television and NPR's "All Things Considered," lectured at the Smithsonian Institution and worked at observatories around the country and in Chile. He is a former national education coordinator for the American Astronomical Society and staff astronomer at the Space Telescope Institute at Johns Hopkins University in Baltimore, Md., where he was responsible for one of the Hubble Space Telescope's original instruments.

Duncan encourages people to camp out to see the Perseid meteor shower and to stay up late for optimum viewing. While the best shower will come in the early morning of Aug. 12, there will be half to two-thirds as many meteors visible during the early morning of Aug. 11 and Aug. 13.

Friends of CU Astronomy will have a meteor party on the night of Aug. 12 at the CU Mountain Research Station, located on County Road 118 in Nederland. People interested in participating can call Fiske Planetarium at (303) 492-5002 to find out how to become a member, or go to the Web site for information at .