for Red Leftovers
by Lindsey Arent
p.m. 25.Jan.2000 PST
NASA is awaiting results on tests performed on a cloud of extraterrestrial dust left after a large meteor blasted across the Canadian skies, exploding with the energy of at least two kilotons of TNT.
The impromptu data recovery mission flew Friday, three days after one of the largest meteors in a decade blazed across the Yukon Territory, leaving a glowing vapor trail that was visible for hours.
"Scientists are always interested in extraterrestrial particles, and this one was a fresh batch," said Frederick A. Johnson, spokesman for NASA Dryden Flight Research Center in Edwards, California.
The event was seen and heard by witnesses from Alaska through Northwestern Canada, many of whom reported that they heard two sonic booms, smelled a foul odor, and heard "sizzling sounds" as the meteor whizzed across the sky.
NASA officials reported the event caused a bright fireball in the sky that was detected by defense satellites and seismic monitoring equipment.
The last major meteor event occurred in June 1908, when a major explosion rocked the skies above Siberia in Russia, near the Tunguska River.
The blast was estimated at 20 megatons of TNT and flattened trees in its path for 40 miles around. Scientists hope to learn more about the Tunguska event through analysis of the Yukon explosion.
NASA officials said in a statement that the meteor was likely to have been a sporadic meteor, a collection of tiny dust particles that bubble off comets as they pass close to the sun and hit the Earth.
After hearing about the meteor, NASA officials decided to send a specially equipped airplane through the debris cloud to learn more about the source of the meteor. But due to a mechanical snafu, the plane wasn't able to get to the region until three days after the event.
"We lost a day to a maintenance problem," Johnson said, adding that it takes a day or so to arrange a sudden unscheduled flight.
NASA sent an Airborne Sciences ER-2 aircraft to the site to perform high-altitude science experiments. Scientists collected meteor debris from 65,000 feet up with an Aerosol Particulate Sampler, a system of five-inch paddles that are exposed to the dust from the craft's wingtip.
After exposure, the paddles were drawn into a "hermetic enclosure" and sent to NASA's Johnson Space Center in Houston for testing.
Special photos were taken of the region as well, to identify any craters or damage inflicted by the meteor.
Johnson Center scientists were unavailable for comments on the tests.