NASA: Fireball was likely 10-foot asteroid
PHOENIX - NASA believes the fireball which lit the pre-dawn sky over Phoenix was a small asteroid burning up in Earth's atmosphere.
In a news release, the space agency wrote: "Based on numerous eyewitness accounts, a small asteroid estimated at 10 feet (3 meters) in diameter – with a mass in the tens of tons and a kinetic energy of approximately 10 kilotons – entered Earth’s atmosphere above Arizona just before 4 a.m. local (MST) time. NASA estimates that the asteroid was moving at about 40,200 miles per hour (64,700 kilometers per hour)."
Witnesses report a loud boom and the night sky lighting up at 3:48 a.m. Surveillance video shows area residences lit up like daylight for a few seconds as the event passed.
In fact, NASA reported difficulty analyzing video and pictures of the event since cameras were completely saturated with light as it flared, essentially blinding them for a moment.
The event brought on a spectacular light show, leaving behind a colorful trail that hung in the skies till well past sunrise.
Very little of the object is likely to have made it to the ground, said Josh Bangle with the Lowell Observatory in Flagstaff.. "Specks, maybe."
"There's always small objects entering Earth's atmosphere," Bangle said. His observatory tracks 50 to 200 a night.
NASA said, over the past 20 years, about 600 small asteroids like Thursday's have entered Earth's atmosphere and exploded spectacularly. Scientists refer to such objects as bolides.
Most, of course, do not make such a noticeable bang. But occasionally we get a big one.