A sonic boom was heard and felt across North Alabama shortly after 13:40 CST (19:40 UTC) on November 14, 2017. At this time, there is still no official explanation.
Numerous Alabamians, primarily from Blount, Jefferson, Walker, Cullman, Talladega, Calhoun, Clay, Winston, Randolph, Tuscaloosa, and St. Clair counties took to Twitter to report the event shook their homes. There are also reports of the sound being heard in Columbus, Mississippi.
ABC 33/40's chief meteorologist James Span said the sound does not appear to be related to a geological event but at this time there is still no official explanation.
The National Weather Service in Birmingham has not confirmed the source of the sound but believes it originated from an aircraft breaking the sound barrier or a meteorite from the Leonid shower.
Home video during the "Bama Boom" today at 1:49 p.m. CST.... from Amy Phelps pic.twitter.com/ZQQIL6NmFz— James Spann (@spann) November 15, 2017
Re: loud boom heard: we do not see anything indicating large fire/smoke on radar or satellite; nothing on USGS indicating an earthquake. We don't have an answer, and can only hypothesize with you. 1) sonic boom from aircraft; 2) meteorite w/ current Leonid shower?— NWS Birmingham (@NWSBirmingham) November 14, 2017
Bama booms detected on a seismograph in Cleburne County… https://t.co/QRhl5CdpYm— James Spann (@spann) November 14, 2017
Should be hearing from the team at NASA in Huntsville soon for possible explanation of today’s Bama Boom around 1:45p CT… stay tuned…— James Spann (@spann) November 14, 2017
A sonic boom is the sound associated with the shock waves created by an object traveling through the air faster than the speed of sound. Sonic booms generate significant amounts of sound energy, sounding much like an explosion to the human ear.
Supersonic flight and sonic booms
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November 15 @ 12:00 UTC
NASA scientists in Huntsville, Alabama, said Tuesday night that the origin of a mysterious boom that rocked central Alabama earlier Tuesday "remains unclear." However, the sound wasn't caused by a Leonid meteor, they said.
Bill Cooke, head of NASA's Meteroid Environment Office at the Marshall Space Flight Center, released what the office knows so far Tuesday night:
1. Seismic data from the U.S. Geological Survey's Lakeview Retreat near Centreville, Alabama, show a fairly loud boom occurring on or before 13:39 CST.
2. The Elginfield Infrasound Array in southern Ontario 965 km (600 miles) from North Alabama "picked up a matching infrasound signal beginning at 14:02 and lasting around 10 minutes." NASA said the signal "could have been generated by a bolide, larger supersonic aircraft or a ground explosion."
3. Eyewitnesses reported a vapor trail, and NASA said that points to a meteor or aircraft.
"The sound wasn't caused by a Leonid meteor. The Leonid meteor shower is occurring this month, but Leonid meteors are small and never penetrate low enough into the atmosphere to produce sounds audible on the ground."
Featured image: Sonic boom reports in North Alabama on November 14, 2017. Credit: Google. Edit: TW