Residents in Alabama were left baffled last week when a loud boom resounded across much of the state.

The boom, nicknamed ‘Bama Boom’, has left experts stumped, with suggested causes ranging from supersonic aircrafts to meteors exploding in the atmosphere.

The Birmingham National Weather Service originally hypothesized that the sound could have come from a supersonic aircraft or a meteor breaking the sound barrier, possibly from the Leonid meteor shower that peaks on November 17 and 18.

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

However, the head of NASA’s Meteoroid Environment Office (MEO) at the Marshall Space Flight Center in Huntsville, Alabama, Bill Cooke, has since cast doubt on the theory that the boom could have been caused by a Leonid meteor.

Cooke told ABC 3340 that the “Bama Boom,” as it has become known, could have been caused by a supersonic aircraft, a ground explosion, or possibly a bolide—a large meteor that explodes in the atmosphere unrelated to the Leonid shower.

The noise from the boom was picked up by the U.S. Geological Survey’s Lakeview Retreat near Centreville, Alabama. However, seismic data suggests that the boom was not the result of an earthquake-related event.

The most common source of mysterious sonic booms are unannounced military flights in supersonic jets. Such a flight could very well be the source of the Bama Boom. ABC 3340 reached out to Maxwell Air Force Base in Alabama, however that base primarily houses training colleges such as the Air Force Officer Training School and Air Force ROTC. The 908th airlift wing is stationed at Maxwell, but they fly subsonic C-130s.

However, any one of a number of Air Force Bases could be the source of a supersonic jet, such as Robbins Air Force Base just to the east in Georgia, which maintains the country’s F-15 Eagles. The military may make an announcement following the flight tests, or NASA scientists might determine that the source was in fact an exploding meteor in the atmosphere. Until then, Alabamians will just have to look up to the sky and wonder.

The British Journal Editors and Wire Services