(CNN) -- What burns five times brighter than a full moon and flies through the air with its tail sticking out behind it?
Many Texas residents reported seeing a meteor streaming across the Saturday night sky.
They were right, but scientists are still investigating the details, said Dr. Bill Cooke, lead for NASA's Meteoroid Environment Office.
"This was definitely what we call a fireball, which by definition is a meteor brighter than the planet Venus," he told reporters in a conference call Sunday.
"This event was so bright that it was picked up on a NASA meteor camera in the mountains of New Mexico over 500 miles away, which makes it extremely unusual," he said. "This was a very bright event."
Based on data from NASA's camera, Cooke estimated that the meteor was at least four feet wide, weighed about 4,000 pounds and burned five times brighter than a full moon.
The American Meteor Society has received more than 200 reports about it so far from people in various parts of the Lone Star State, who reported seeing it within minutes of the same time -- 8:45 p.m. Central (9:45 p.m. ET). Descriptions of the fleeting flash spread rapidly on social media.
At least two Texas residents apparently caught it whizzing by on camera -- one of them snapped a photo, the other recorded a dash cam video. A YouTube user posted it online.
Did any pieces of it make their way to Earth?
It's possible meteorites from the fireball hit the ground, Cooke said.
To find out, investigators will be looking at things like weather radar data, he said.
The Maverick County Sheriff's Department reported around 8:45 p.m. that the ground shook when a meteorite landed, the National Weather Service in San Antonio said.
Where did the fireball come from?
When a piece of a comet or asteroid hurtling through space enters the Earth's atmosphere, pressure causes it to break apart violently in an explosion, Cooke said.
The fireball that Texans spotted Saturday night could have come from the North Taurid meteor shower, which is going on right now and is known for producing bright fireballs, Cooke said. It also could have been part of Comet Encke, or a piece of rock from the main asteroid belt between Mars and Jupiter, he said.
"We're going to have to wait until we get more data to discriminate," Cooke said.
Why did so many people notice it?
A NASA camera near Mayhill, New Mexico, captured an image of the sky that shows the brief, bright flash around 8:40 p.m. Central Time. Another camera in Las Cruces, New Mexico, didn't capture the event itself, but detected a change in the sky's brightness because of the fireball.
Fireballs aren't uncommon, Cooke said.
Thousands of them occur in the Earth's atmosphere each day, the American Meteor Society says. But most of them happen over oceans or uninhabited areas -- or are masked by daylight, the society says.
"A city dweller in the U.S. might expect to see events this bright once or twice per year," Cooke said.
But depending on what time they hit, they tend to draw more attention.
"This one was around 8:40, so there were a lot of people outside and those events get a lot of notice," he said. "There would have been far fewer reports if it happens around 3 a.m."