Harveylives
11-13-2003, 01:15 PM
Rare Double Meteor Shower Begins Thursday
Irene Mona Klotz, Discovery News
Leonid Meteors as Seen in Japan, 2001
Nov. 12, 2003 — It won't have the pizzazz of the 2001 show, but the annual Leonid meteor shower does offer early-morning risers a rare treat this year: a double performance.
"Normally there's just one Leonid meteor shower, but this year we're going to have two," said Bill Cooke with NASA's Space Environments Group at the Marshall Space Flight Center in Huntsville, Ala.
No, Earth isn't back-tracking in its orbit. Every year, the planet passes through a particularly dusty region of space, the result of debris shed by Comet Tempel-Tuttle, which swings through the inner solar system every 33 years. With every visit, the comet leaves behind a fresh trail of comet dust.
"Our planet glides through the debris zone every year," Cooke said. "It's like a minefield. Sometimes we hit a dust trail, sometimes we don't."
This year, Earth will come close to two trails, sparking an unusual show a week before the annual shower. The preview shower peaks early Thursday morning as the planet cruises past a debris trail shed by the comet in 1499.
If skies are clear, viewers in Alaska, Hawaii and the Pacific rim of Asia will have the best view. Experts predict sky-watchers in Alaska, Japan and China will be able to see about one shooting star a minute.
The second show occurs a week later when Earth zooms past a comet trail left during Tempel-Tuttle's 1533 visit. This shower, which peaks about 2:28 a.m. EST on Nov. 19, will be mostly visible along the East Coast of the United States as well as in Western Europe.
No special equipment is needed to view the meteor storm, which is called the Leonids since the shooting stars seem to stem from the general direction of the constellation Leo. The meteorites actually are pieces of comet dust that hit Earth's atmosphere at about 150,000 mph — 40 times faster than a speeding bullet — and incinerate. Most of the material is about the size of a few sand grains, though some can be as big as a marble.
Peak rates come when the planet zooms through the center of a stream. The 2001 shower, for example, sparked more than 1,000 shooting stars an hour.
Irene Mona Klotz, Discovery News
Leonid Meteors as Seen in Japan, 2001
Nov. 12, 2003 — It won't have the pizzazz of the 2001 show, but the annual Leonid meteor shower does offer early-morning risers a rare treat this year: a double performance.
"Normally there's just one Leonid meteor shower, but this year we're going to have two," said Bill Cooke with NASA's Space Environments Group at the Marshall Space Flight Center in Huntsville, Ala.
No, Earth isn't back-tracking in its orbit. Every year, the planet passes through a particularly dusty region of space, the result of debris shed by Comet Tempel-Tuttle, which swings through the inner solar system every 33 years. With every visit, the comet leaves behind a fresh trail of comet dust.
"Our planet glides through the debris zone every year," Cooke said. "It's like a minefield. Sometimes we hit a dust trail, sometimes we don't."
This year, Earth will come close to two trails, sparking an unusual show a week before the annual shower. The preview shower peaks early Thursday morning as the planet cruises past a debris trail shed by the comet in 1499.
If skies are clear, viewers in Alaska, Hawaii and the Pacific rim of Asia will have the best view. Experts predict sky-watchers in Alaska, Japan and China will be able to see about one shooting star a minute.
The second show occurs a week later when Earth zooms past a comet trail left during Tempel-Tuttle's 1533 visit. This shower, which peaks about 2:28 a.m. EST on Nov. 19, will be mostly visible along the East Coast of the United States as well as in Western Europe.
No special equipment is needed to view the meteor storm, which is called the Leonids since the shooting stars seem to stem from the general direction of the constellation Leo. The meteorites actually are pieces of comet dust that hit Earth's atmosphere at about 150,000 mph — 40 times faster than a speeding bullet — and incinerate. Most of the material is about the size of a few sand grains, though some can be as big as a marble.
Peak rates come when the planet zooms through the center of a stream. The 2001 shower, for example, sparked more than 1,000 shooting stars an hour.