While meteors bombard Earth daily, most streak across the sky only briefly before burning up. But on October 3 of last year, a meteor apparently cut into and then out of Earth’s atmosphere, circled the globe, and crashed to Earth 100 minutes later.
Most observers thought they had witnessed the fiery passage of two separate meteors that night--one burning through the sky over Las Cruces, New Mexico, and another that broke apart over the Sierra Nevada in California. But ucla geochemist John Wasson and physicist Mark Boslough of Sandia National Laboratories in Albuquerque reconstructed the trajectory of the events and say that a single meteor is the most likely explanation.
The meteor, they say, after passing above Las Cruces, streaked north and east until it faded out of view near Amarillo, Texas. Wasson and Boslough believe the meteor passed through the upper atmosphere and into space somewhere over Texas or New Mexico and was slowed by atmospheric friction until it had just enough speed to make a near complete orbit of Earth. (A similar braking maneuver is planned for the Mars Global Surveyor scheduled to reach that planet in September.) The meteor finally exploded some 24 miles above the eastern Sierra Nevada, near the town of Little Lake. Some fragments may have fallen into the lake for which the town is named.
Boslough says the meteor was just one of several seen within 24 hours from locales as diverse as Mexico and the Czech Republic. It’s not known what caused the meteor shower. It doesn’t appear that everything came in from the same direction, Boslough says, adding that it could have been caused by debris from an impact on the Moon or an asteroid that had been pulled apart in space.
Boslough estimates that the meteor weighed about ten tons when it exploded, and eyewitnesses say bits were breaking off along its path in New Mexico and in California, so it may never be known how big the original object was. Wasson has offered a $5,000 reward for the first person to bring in a walnut-size chunk of the meteorite. Hundreds of people have brought in all manner of rock, but so far no one has found a piece of the real thing.
