Mystery boom stock
It's louder than fireworks, a transformer explosion or even a train. "This is five times as loud as that," said Theresa Smith of Lyndon.

"The sounds I hear have nothing to do with trains. More like muffled dynamite," former CSX engineer Scott Gaw weighed in.

People living in Lyndon, St. Matthews, Hurstbourne, Graymoor Devondale, Woodlawn Park and surrounding neighborhoods have been discussing mysterious, recurring booms for months. The booms have sparked several active conversations on the Nextdoor App as well as Facebook groups. No one seems to know the source of what they're hearing, but they agree, it's loud-sometimes loud enough to shake a house.

In January, Barbara Martin says she was watching the football playoffs at a friend's house in Jeffersontown near the Gene Snyder when two loud booms shook the house.

In a quest for answers, some homeowners have started conducting research of their own. Jennifer Whitfield called local utility companies, police and fire departments. Based on reports from neighbors in her area, she believes the source of the booms is within a three to five mile radius of Holiday Manor. "The general time seems to be 8:00 pm to 8:30 p.m.," Whitfield says. Other neighbors have reported hearing the booms as late at 10:40 p.m. and as early as 4:00 a.m. Some even say they've seen a flash of light associated with it.

"Sometime around November... I had my own experience," says Matthew Messer of St. Matthews. "I had just turned east on Columbia Avenue from Marquette Drive when I happened to notice a single bright light shoot up into the sky behind me, followed by what sounded like a mortar type firework being launched. About five seconds later, right as I was about to turn left... I heard a very loud explosion that genuinely surprised me, as it was much louder than a standard mortar-type firework."

These mysterious booms have been reported in East Louisville during all seasons and at all hours of the day. So, what are they and from where are they coming? WLKY took some rumored theories to the experts.

We first reached out to Fort Knox to investigate if the source could be military exercises known to carry sound. Media Relations Officer Kyle Hodges requested specific dates and times so he could check the base's training log. None of them checked out. Hodges says, "My Range Control team does not believe we were the source of the booms. They checked the dates and times you sent against their training log and could not find a direct correlation. Training was complete well before the times mentioned on Jan. 6 and 13. On Jan. 12, we did have an engineer unit conducting light demolition training from 8:00 a.m. to 10:00 p.m., but they don't believe the sound of that specific type of training would've carried much farther than the Radcliff area - definitely not enough to shake folk's homes in east Louisville."

Hodges' team recommended checking with the FAA to see if anything supersonic was flying through that area at the designated times.

FAA Frontline Manager Mike Shaw says he's not aware of any booms related to air traffic. "If it happened in Lyndon, we'd know it. Our office is off Hurstbourne Lane and we have had no complaints to our office." Shaw says it's been at least five years since he's heard complaints about military helicopters in the area, and he says it's a much different sound than the boom described. Shaw recommended we double check with Air Traffic Control at Standiford Field.

Unfortunately, that didn't lead to answers either. Air Traffic Control employee Stephanie Kimmel says, "My supervisors and I checked the log with the dates you gave me and I didn't see anything out of the ordinary."

WLKY then reached out to Kentuckiana Seismic & Survey, Inc., once again sending a list of specific dates and times. Vice President Joey Hopper responded saying, "Of the projects that Kentuckiana Seismic & Survey is involved on, we have no blasting projects that were operating in those locations on those dates.

Similar responses came from representatives with the Kentucky Transportation Cabinet as well as Louisville's Department of Public works and Transportation Department: no projects in the area and no known blasting that would cause the booms.

WLKY also reached out to officials with Graymoor Devondale Police, Lyndon City Hall and the St. Matthews Fire Department. Representatives from each say they've heard complaints-some have even heard the booms-but they did not know the source.

A Google search of "mysterious booms" suggests frost quakes could be the answer. A frost quake occurs when underground water freezes and expands quickly. The expansion pushes against soil and rock and can cause the ground to crack, creating a boom. WLKY Meteorologist John Belski says a frost quake is not likely the source of what people in Louisville are hearing. "When Chicago had 25 below they were having frost quakes, and even Cincinnati had a few, but I haven't heard of any in our area. It's more of an extreme cold phenomenon," he says.

Another theory that didn't pan out-local rock quarries. WLKY reached out to Rogers Group Inc, Jefferson County Stone in Louisville. Company representative Scott Chancellor says they conduct underground blasting, "but you wouldn't be able to hear it. We're so deep underground." He says the only other quarries in our area are in Oldham and Bullitt Counties and it's a similar situation there.

Finally, WLKY reached out to U.S. Geological Survey Geophysicist John Bellini, who's based in Golden, Colorado. Bellini says, "Generally booming sounds are not easily recordable by seismometers. We're not seeing anything in Kentucky, and we haven't seen anything in that area for a while. We can occasionally can pick up a booming sound if it's happening near a seismometer, for example a natural gas explosion, but these instruments are not built to detect booms. Seismometers are meant to pick up movement in the ground." Bellini double checked his records with four specific reports of the booming sound in our area.

January 2 at 8:15 p.m. in Lyndon, KY

January 6 at 10:00 p.m. in Lyndon, KY

January 11 at 4:06 a.m. in Lyndon, KY

January 12 at 10:44 p.m. in Jeffersontown, KY

"I looked at our nearest station and nothing came up. I even looked at the records from stations as far as an hour away and nothing turned up there either." Bellini reiterated, "This is typical with booming sounds."

WLKY reached out to the University of Louisville's Geology Department and are waiting to hear back.

Have you heard the booms? Can you record them? If so, please send video or tape recordings to