The source of an enormous boom heard by some across parts of Mississippi on Sunday afternoon remains a mystery.

James Hill, director of the Rainwater Observatory in French Camp, said the the loud, long noise Grenada Countians heard could be anything from a jet sonic boom to a meteorite exploding.

"We haven't had any reports at the observatory of a meteor," he said.

Grenada Countian Rina Chaney said she was sitting on the front porch with her daughter in the Hardy community Sunday at 2 p.m. when they heard what she described as "a long crack of thunder."

"We live near the interstate, but we didn't think anything of it until reports started coming in," she said.

Grenada County Sheriff Alton Strider said the department received numerous reports of people hearing loud booms.

"I was told there were calls as far down as Hattiesburg, and have heard different things, but I can say officially that we did get a loud boom," he said. "The reports are more severe the further south you get."

According to Jeff Rent, a spokesman for Mississippi Emergency Management Agency, the agency received reports from Carroll County of a fire ball in the sky, the earth shaking, and a boom, but no indications of an impact.

According to seismic activity information released by the United States Geological Survey, no activity was reported in Mississippi on Sunday.

Meteorologists with the National Weather Service believe the events could be attributed to the Gamma Normids, a meteor show that runs from Feb. 25 to March 22.

The show peaked Saturday, and can produce one meteor per hour in the northern hemisphere.