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Web Extra:  July 25, 2001

Meteor explosion shocks chance observers in eastern U.S

From Virginia to New York, observers described bright lights in the sky and a boom Monday evening around 6pm. Variously described by watchers as: a bright yellow streak moved rapidly across the sky, trailed by a plume of white smoke; like a plane engulfed in flames; a big red ball in the sky. Less than a minute after the fireball was gone, they said, came a loud boom that shook windows. ''It almost sounded like when you're at the fireworks and they send out the one to just kind of make noise,'' an observer said.

“I don’t think it was a meteor shower,” says Tim McCoy, meteorite curator at the Smithsonian Museum of Natural History. He describes showers as the burning up of a dust trail from comets, and Monday’s event was brief and apparently the result of a single object. Also, McCoy says, since meteor showers derive from comets they are “highly predictable.” This event was certainly unexpected.

Alexander Wolszczan, an astronomy professor at Pennsylvania State University, told the Associated Press that the shaking people felt and the boom they heard could have resulted from a sound wave produced by a meteor breaking apart in the atmosphere. A meteor shower is normally a silent event, he said, but large meteors can create concussive sound waves, or sonic booms, that can be heard up to 100 miles from an object's path.

The most extreme reports about the meteorite’s splashy entrance include broken windows from the sonic boom, and even a cornfield scorched by a hot meteorite. “It’s very hard to believe,” McCoy says. “[Meteorites] never hit the ground as fireballs. They are 10 miles above the Earth when firey. They fall slowly, a couple of hundred miles per hour, through cool air. By the time they hit the ground, they’re cold.”

Occasionally, bits of space rock survive the journey through the atmosphere. Sightings of possible meteorite remains have been claimed throughout the Northeast, including New York, New Jersey and Pennsylvania. Still the sensible skeptic, McCoy cautions that a meteorite actually lands less than 50 percent of the time, and even then it’s quite difficult to predict a landing spot. “Someone’s either going to find a rock or not,” he says. If you want to hunt for a remnant anyway, MocCoy says to look for a rock burnt on the outside and light on the inside, possibly containing metallic fragments.

McCoy also mentioned a similar incident from Peekskill, N.Y. in October of 1992. In that case, a hole in the trunk of 1980 Chevrolet Malibu was chalked up to random violence, until a 27.3-pound meteorite was discovered underneath the car.

Emily D. Johnson

For an update, see the story on Science@Nasa.



This page was  updated July 27, 2001

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