For many people in Nevada and northern California, Sunday morning was disrupted by a sonic boom and a fireball streaking across the sky.
According to the Associated Press, the unannounced pyrotechnics prompted a flood of 911 calls in both states.
"It knocked me off my feet and was shaking the house," said a mother in Arnold, Calif., who said she heard a booming sound at about 8 a.m. "It sounded like it was next door."
Those who happened to be looking at the sky say they saw a blazing light hurtling across the sky.
"It is an event that makes you glad to be alive," Matthew Neal of San Francisco told the AP. "The main body was bright green and the head was bright red and white."
The fireball, which was visible in towns some 600 miles apart, was almost certainly what astronomers call a bolide, an exceptionally bright meteor. The loud crack was likely a sonic boom caused by the meteor's shockwave.
SPACE.com's Denise Chow quotes Bill Cooke, the head of NASA's Meteoroid Environments Office at the Marshall Space Flight Center in Huntsville, Ala., who estimated that the meteor was moving at about 33,500 mph, weighed more than 150,000 lbs., and was roughly the size of a minivan. The energy released by the meteor as it entered the atmosphere was equivalent to about a fourth of the energy of the atomic bomb dropped on Hiroshima, he said.