On March 19th at 11:19 Central Time, a meteoroid entered Earth's atmosphere over the southeastern United States and disintegrated in a flash as bright as the crescent Moon. To the human eye, it appeared to be a garden-variety fireball, the kind that appears almost every clear night, but NASA cameras had a different story to tell.

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© NASA
"This was an unusually low-flying meteor," says Bill Cooke of NASA's Meteoroid Environment Office. Cooke and colleagues operate a pair of all-sky cameras, one in Huntsville, Alabama, and another in Chickamauga, Georgia. Both cameras caught the fireball, allowing rapid triangulation of its flight path. "It was first recorded at an altitude of 72.9 km (45.3 miles) and burned up at an altitude of 32.5 km (20.2 miles)."

That's low. Most meteoroids disintegrate around 70 to 80 km high. This one held together for a much deeper descent. "It had a lot of structural integrity. Maybe it was a metallic object," speculates Cooke. "Based on the brightness and velocity of the fireball, I estimate a mass of about 10 kilograms and a diameter of ~20 centimeters - a decent size!"

Cooke's meteor mini-network is "smart." When both cameras catch a fireball, the system's software springs into action and immediately calculates a flight path and orbit for the meteoroid. Cooke receives an email alerting him to interesting events that might otherwise have gone unnoticed. "In the near future, we plan to expand our network along the eastern seaboard of the United States," notes Cooke. "With smart cameras on duty, who knows what we might find?" Stay tuned for the unexpected.