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From: bogus_at_does.not.exist.com_at_meteoritecentral.com
Date: Thu Apr 22 12:26:27 2004 Message-ID: <mailman.22.1082651187.99198.meteorite-list_at_meteoritecentral.com> As many as 75 percent of the shooting stars that would have been visible were outshone by the Moon, astronomers had predicted before the event. A full analysis of the spectacle won't be completed for days. Europeans were to see a good show, forecasters had said, while North Americans were thought to have the best seats. Behind the shower The Leonids occur every November, when Earth passes through a complex network of dust streams laid down by a comet called Tempel-Tuttle. The comet rounds the Sun every 33 years, and on each pass through the inner solar system it leaves a fresh stream of particles in a slightly different location. [The Science of the Leonids] Over centuries and millennia, these streams all spread out, mingling and creating a giant river of stuff ranging in size from sand grains to marbles. In normal years, Leonid meteor rates top out at a few dozen per hour, or near one per minute. Only when our planet travels through a dense stream put down relatively recently can outbursts like this year's occur. This morning, Earth waded into the middle of streams that Tempel-Tuttle had deposited in 1767 and 1866. The older stream was to generate a peak of activity over Europe at around 0400 UT. The newer stream fueled the more active North American peak. Other bits of debris that had been drifting through space for thousands of years also contributed to the show. Timing dictated that people in Asia and the Southern Hemisphere were not well positioned for this year's grand displays. What's next? No significant Leonid storms are expected again until 2033 or later. Another major storm won't likely occur until at least 2098. Meanwhile, the Perseid meteor shower, an annual August event, could kick up to storm level in the year 2028. This year's Leonid display will tail off quickly now. Only a sprinkle of shooting stars will be visible each hour between midnight and dawn Wednesday. The next chance to see a nice meteor shower will be on Dec. 14, when the annual Geminids are expected to put on a fine display. Editor's Note: This story was updated at 9:22 a.m. and will be updated again later today as more reports roll in. Received on Thu 22 Apr 2004 12:24:32 PM PDT |
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