The source of what sounded like a loud explosion, heard by residents of Smackover and possibly the surrounding areas Monday night, was unknown as of Tuesday afternoon.
Larry Burchfield, a Smackover resident, said he heard the explosion sound sometime between 9 and 9:30 p.m. He was at his home near Cross Oil, he said.
Other Smackover residents took to Facebook in search of an explanation of the sound, some also reporting feeling their houses shaking from the force of the sound.
Union County Emergency Management Director Bruce Goff heard about the sound from Burchfield, he said, but was still too early in his investigation to have any leads into what might have caused it.
"All I can do is ask the other agencies in this area if they've had any response to anything, or if they've found anything," Goff said. "I really don't know which way to go."
An employee at Cross Oil said the sound didn't originate there; she said she heard from another employee it might have been someone blowing up a beaver dam. Goff said that explanation is plausible.
"That's a strong possibility because they do use Tannerite for that... There are some timber companies around that do use private contractors who come in and remove beaver dams, and Tannerite can be purchased, depending on the amount, by a private citizen," Goff said.
Rick East, recorder/treasurer for the City of Smackover, said the sound did not originate in the city.
"There was a loud explosion somewhere, but it wasn't in Smackover," East said. "No one here knows... We've heard rumors that someone heard it all the way down in Bernice, Louisiana, so it may have been further down."
An employee at the Arkansas Game and Fish Commission's South Central Office in Camden also said she hadn't heard anything about the loud sound.
John Brown, a security officer at Highland Industrial Park, where south Arkansas's aero-defense industry is based, said no one at the park's 24/7 security office Monday night heard or saw anything strange.
"From time to time, there is some testing that one of the tenants has done after hours, but last night would not be one of those nights," he said. "After checking, there was nothing that came from out there... Nobody heard anything or saw anything out of the ordinary."
Scott Ausbrooks, State Geologist and director of the Arkansas Geological Survey, said nothing registered at any of the AGS' south Arkansas heliocorders (the devices that record signals from seismometers).
"I don't see anything on there," he said, noting that Arkansans can look at the seismograph data themselves by visiting the AGS website, and pointing out readings from a large earthquake in Indonesia that appeared on the Richland Creek Farm heliocorder shortly after noon on Monday.
"A lot of times, when you hear these big explosions, it could be bolides – meteors – basically disintegrating in the atmosphere and making a shockwave," Ausbrooks continued. "This is strictly speculation on my part ... We get these calls and it's so hard to tell people we just don't know. Usually, you see light associated with (a meteor), but if it's cloudy, you're not going to see the meteor. But when you're talking about that kind of area and the explosion's not big enough to show up on my seismometer, that's why I think it's in the atmosphere."
Marty Mayeaux, a meteorologist at the National Weather Service, checked the Shreveport and Little Rock office's historical radars, but couldn't find anything at the time Smackover residents heard the sound.
"Meteors are kind of impossible to track," he said. "You're trying to take a picture of something that's happening at such a small interval – it's almost impossible to catch it unless it's happening at the same time the radar is taking a picture... They're moving so fast that even when it does capture a picture, it's just catching a dot, not a trail."
Dr. Clay Sherrod, director of the Arkansas Sky Observatory, said in an email that it is possible the sound was caused by a meteor.
"Checking several atmospheric and meteoric databases, I am seeing no reports at all of a bright bolide or meteor that could have been responsible, but that does not mean one did not pass by," he said in an email. "Meteors that DO create sonic booms are typically a bit frighteningly close to the surface of the earth, but rarely impact. Most are burned up by friction as they pass through the earth's air, some at speeds approaching 40,000 MPH."
Sherrod noted that he hadn't received any reports of visual sightings of a meteor, but emphasized that that doesn't mean there wasn't one.
"It may not have been seen and still created a sonic boom, which is quite common for larger and faster meteors, as they pass through the atmosphere and create a concussion of air ahead of them. Thus the meteor could have created an explosive sound either through direct impact to the ground or simply through the sonic boom effect," he said.
The News-Times also reached out to the Space Weather Prediction Center, Union County Sheriff Ricky Roberts and the Union County Judge's office about the noise, but had not heard back by press time on Tuesday.
Readers can send their own reports about the sound to the News-Times at [email protected].