A chunk of space rock is likely the object many saw streak across the sky Saturday evening above the greater Chattanooga area.
Dr. Bill Cooke, a NASA meteor scientist, said in an email late Saturday evening that preliminary information indicated a bit of space debris entered the Earth's atmosphere above northern Alabama, igniting a fiery trail through the sky.
He believed the meteoroid moved southeast, "finally burning up over Atlanta."
He said the only video available Saturday night was from a mobile phone, but based on that, he estimated the brightness of the meteor "to be similar to the crescent moon, which means the meteoroid was a few inches in diameter."
A meteoroid can potentially travel many thousand miles before encountering Earth.
"When it hits the atmosphere at speeds of tens of thousands of miles per hour, it burns up ['ablates'], leaving a streak of light we call a meteor or shooting star. If any fragments of the rock survive to the ground, those pieces are called meteorites," Cooke wrote.
"A fireball is a meteor brighter than the planet Venus," he wrote.
Robert Lunsford, with the American Meteor Society, also said it was "too early to know for certain" about the object. But, he wrote, "it was most likely a random meteor."
According to www.amsmeteors.org, there have been 2,140 meteor "events" so far this year.
Lunsford said this is high time for random meteor activity in the Northern Hemisphere.
"We are at a point in the year where the sporadic (random) meteor activity is at its highest as seen from the northern hemisphere," he wrote. "This may explain why we are seeing quite a few fireballs recently."
Saturday night, more that 80 witnesses claimed on the meteor society's website they witnessed the glowing phenomenon, some from as far away as Maryland.
In response to a Times Free Press query on Facebook, hundreds of local witnesses described the fireball.
"I saw it for at least 15 seconds - which seemed like an eternity," Matt McLelland wrote in an email. He said it was visible from the Wine over Water event at the Walnut Street Bridge and appeared over AT&T Stadium, then headed toward Erlanger.
Laurie Hadwyn-Janes, a Chattanooga attorney, wrote that she was biking near the Hunter Museum when she and others saw it.
The fireball moved "all the way across downtown then it disintegrated - giant sparkly ball of fire all the way across downtown," she wrote. "I screamed and pointed 'What is that?' Everyone was gasping - it was a once in a lifetime blessing from God - amazing!"
Contact staff writer Alex Green at email@example.com or 423-757-6731.