for National Geographic News
Some meteorologists will tell you that a butterfly flapping its wings in Beijing could trigger a chain reaction that starts a thunderstorm in Manhattan.
But until recently it was thought that a 33-foot-wide (10-meter-wide) meteor crashing through Earth's upper atmosphere would have little effect.
Now an unlikely team of researchers and a million-to-one observance of such an event are telling another story: When meteors vaporize in our atmosphere, they leave behind much more debris than scientists previously thought.
This cosmic dust may, in turn, affect our planet's atmosphere.
Last September, a 33-foot-wide meteor struck Earth's atmosphere. The resulting fireball attracted the attention of a research team at Los Alamos National Laboratory in New Mexico whose primary mission is to detect nuclear explosions.
"It was exciting enough to be able to chart this fireball with the new satellite systems and other detectors that we have in place," said Doug ReVelle, a team leader. "The chances that it fell at that exact location in the [Antarctic] are absolutely astronomical."
"Astronomical" because the meteor fell near researchers from the Australian Antarctic Division.
The scientists were in Antarctica measuring the polar atmosphere with lidar, a laser-based cousin to radar that can determine the composition and density of environments.
The meteor deposited 2.2 million pounds (a thousand metric tons) of debris in the Antarctic sky, forming a vertical cloud high in the zone where the researchers were scanning.
"The readings were so odd that they thought they had an equipment malfunction. But fortunately they kept measuring through it," said Peter Brown, an astrophysicist at the University of Western Ontario in Canada who later helped the team interpret the data.
Realizing that the readings were tied to the same asteroid tracked by researchers at Los Alamos National Laboratory, Brown and other scientists began to study data from Los Alamos and Antarctica.
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