ANNAPOLIS – One of the most spectacular Leonid meteor showers in decades will be visible from North America early Sunday morning, astronomers say – a tantalizing forecast for Maryland skywatchers.
Each year, the Earth passes near a stream of debris from comet 55P/Temple- Tuttle. Most years, that trail provides Earthlings with a view of a smattering of bright meteors during mid-November as dust from the edge of the debris cloud grazes the atmosphere. This year, astronomers who study Temple-Tuttle’s trail orbits think Earth will pass directly through one.
“If the calculations are correct, there will be a period of two to three hours where the Earth is intersecting that debris, and we’ll see meteors,” said NASA Astrobiology Institute Chief Scientist David Morrison.
On the East Coast, that peak period will fall between 4 a.m. and 6 a.m., according NASA reports. The combination of the early morning timing, a clear weather forecast and low moonlight interference, increases the chances of a particularly brilliant storm visible from Maryland.
With this in mind, park officials at Soldiers Delight Natural Environmental Area outside Owings Mills are preparing for a crowd of amateur astronomers and other curious Marylanders to gather Saturday evening for pre- shower skywatching.
There, members of the Westminster Astronomical Society will set up field telescopes for the public and present a slide show on the Leonids at the park’s visitor’s center.
“We don’t actually take down numbers (of participants), but I can tell you we’ve had a million calls,” said Alma Martin, who also warned the park will close at 11 p.m., well before peak shower time.
In Baltimore, scientists and public outreach officials at the Space Telescope Science Institute are planning to put together three-dimensional photographs of the shower to study meteor paths.
“We have a group of about 15 volunteers scattered throughout the mid- Atlantic,” said astronomer Forrest Hamilton.
“(The project director) is having us go out and photograph different parts of the sky at different times – we have a list of objects to point the camera at – to try to get stereo images of the meteors as they’re entering the Earth’s atmosphere.”
Other scientists are scrambling to secure sensitive satellite equipment from debris damage even as they prepare to go Leonid-watching themselves.
Helen Hart at the Johns Hopkins University works with NASA’s Far Ultraviolet Spectroscopic Explorer, a telescope that “sees” the universe in ultraviolet. Hart says there’s some concern the larger, seed-sized comet dust could damage the lenses of this and other telescopes in orbit near Earth.
That’s just a matter of pointing the telescopes away from the dust cloud, Hart says. She’ll be at Soldiers Delight with other Johns Hopkins students and professors for the pre-Leonid show.
Part of the excitement surrounding this weekend’s shower is because big Leonid storms have been difficult to predict. The last major shower visible in North America, in 1998, was far more intense than forecasted.
Forecasting techniques have advanced in the past four to five years, Hart and Morrison say, and Sunday’s shower will help validate or refute the prediction techniques being used.
“When the day comes that they can predict these very accurately it will be more dull,” Morrison said. “Or maybe I should say, less exciting.”
For more information on the Leonids, go to the American Meteor Society online at http://www.amsmeteors.org/.