Monday, November 19
Leonid Meteors Roar In On Schedule
Skygazers worldwide got a treat Sunday as the Leonid meteor shower put on its best display in 35 years. This five-image composite by Kazuyuki Tanaka in Japan shows nine Leonids radiating from the Sickle of Leo (center). The Beehive Cluster is at the top. Click on image for larger view.
The best meteor shower in 35 years sent bright shooting stars streaking through the sky before dawn Sunday morning for observers throughout the Americas, the Pacific, and the Far East. Preliminary reports paint a picture of the much-anticipated 2001 Leonid shower matching predictions fairly closely. However, the observed rates of a couple of thousand per hour (as seen by a single observer) fell shy of the most optimistic predictions of between 7,000 to 15,000 per hour.
In Eastern North America, skywatchers under dark skies before dawn counted several hundred meteors per hour an average of one every 5 or 10 seconds, with occasional spectacular bursts (presumably by chance) of two or three at once. A crowd of Sky & Telescope staffers at a lakeshore in Western Massachusetts (under a 6th-magnitude sky) oohed and aahed at blue, green, and red fireballs radiating from the cutting edge of the Sickle of Leo, occasionally lighting the ground with flashes like distant heat lightning. The peak for North America was predicted to arrive around 10:00 Universal Time (shortly before dawn in the East), but rates seemed still to be increasing as morning brightened the sky.
Indeed, observers farther west reported an even more spectacular show a little later. In Kentucky, David Phillips, a meteor observer for 15 years, described seeing roughly a meteor per second under an extremely dark sky. Much of the Midwest was cloudy, but Westerners apparently had the best of it. The peak probably came around 11:00 UT, according to Joe Rao, observing with a crowd of 60 at the Skywatcher's Inn in Arizona. "It was partly cloudy here, with 30 to 70 percent sky obstruction, but you couldn't look up for more than a second or two without seeing a meteor, sometimes four at once," said Rao. "These were 1st and 2nd magnitude. It was the most amazing shower I've seen in over 35 years of watching the sky."
Observing from Fremont Peak, California, Landon Curt Noll observed several bursts of activity including a count of more than 1,500 meteors during a 1-hour interval beginning at 10:45 UT, with more than 600 of those appeared in the 15 minutes beginning at 11:00.
Rates seemed to decline somewhat after about 11:15 UT, but farther west in Hawaii, Stephen J. O'Meara and P. K. Chen were more than satisfied as the radiant rose high in the sky from about 12:00 to 16:00 UT. "We had an absolutely stunning, remarkable, brilliant and continuous display of Leonids," writes O'Meara. "The best activity I have ever seen. Though there was no 'storm' meaning the sky was not filled with meteors falling down like rain the shower did rain meteors and fireballs for four hours."
The biggest peak was supposed to come around 18:00 UT, when Australia and the Far East would be turned into view. Rates did surge again around this time, but judging from early reports, this second peak was only comparable to the first.
Bradley Schaefer reported from Alice Springs, Australia, a personal meteor count that peaked with 660 meteors seen during a 15-minute interval. "They were fast," he writes, "and the bright ones were visible in various colors, primarily red, green, and yellow."
Sky & Telescope will present full reports in the coming months as all the data collected worldwide are analyzed.
Alan MacRobert and Dennis di Cicco
© 2001 Sky Publishing Corp. All rights reserved.