Meteor broke of from an asteroid belt.
NASA says a meteor seen streaking through the sky behind the Gateway Arch in St. Louis was a basketball-size hunk of rock that broke off from an asteroid belt between Mars and Jupiter.
The St. Louis Post-Dispatch reports that experts used hundreds of eyewitness accounts from as far away as South Dakota and Minnesota along with two videos to calculate information about the meteor.
They determined that the approximately 220-pound (98-killogram) rock traveled through the sky Monday night at 33,500 mph (53,910 kph), causing a sonic boom. A NASA weather satellite helped the agency confirm it was brighter than Venus in the sky, making it a fireball.
Bill Cooke, of the NASA Meteoroid Environments Office in Huntsville, Alabama, says it broke into pieces 12 miles (19.3 kilometers) above the ground.