A fireball that streaked over the Southwestern sky Wednesday night was most likely a fragment of an asteroid that entered Earth's atmosphere, a NASA scientist said.
Experts said a fireball - or very bright meteor - was likely to blame when residents from Phoenix to Las Vegas to Southern California's coastal area reported that they saw the light move quickly from west to east at around 7:45 p.m. PT, about 10:45 p.m. ET.
NASA spokesperson Veronica McGregor told CNN that the fireball was a tiny chunk of an asteroid that becomes a meteor when it hits the atmosphere. While it probably incinerated before it reached ground, it's not impossible that a pebble-sized meteorite survived the trip.
The greenish bright light the size of a baseball was spotted by many across Arizona and California and caused a stir on Twitter with most asking, Did you see it? What was that?
I saw something that looked like a falling star, but it must have been a fireball in the atmosphere, one witness told NBCLA. It was huge. It had a green glow in front of it and a white tail. It looked like green fireworks going across the sky.
But others reported the light as yellow or orange, instead of blue or green. Don Yeomans, manager of NASA's Near-Earth Object Program, had an explanation: The bluish-green color suggests the object had some magnesium or nickel in it. And orange is usually an indication that it is entering Earth's atmosphere at several miles per second, a moderate rate of speed, he said.
The first reports came from Riverside County around 7 p.m. on Wednesday. Within a half hour of the first reports, several Orange County residents also reported seeing the lights. After about an hour, reports were coming from all over the West, KCAL reported.
Witnesses observing the light said it took a while to get from one side of the sky to another. It's sort of Mother Nature's shot across the bow, he said. It's an impressive light show, one of Mother Nature's best, said Don Yeomans, a Jet Propulsion Laboratory Fellow.
Ed Krupp, the director of the Griffith Park Observatory in Los Angeles, told KCAL that witnesses were probably seeing a piece of interplanetary debris that passed through the Earth's atmosphere and burned up.
“This kind of thing happens about once a year, or once every few years,” he added.