All afternoon, our newsroom has been flooded with calls, emails and twitter messages, about a loud boom heard in, and around, Mt. Pleasant.

We've gotten emails from Dunes West, Rivertowne Country club, Seaside farms, Hamlin Plantation, Brickyard, and even as far as Isle of Palms.

People who heard the sound described it as a loud explosion that started around 1:45pm, and only lasted for about 30 to 45 seconds. And many of you said your homes shook...

According the US Geological Survey, there have been no signs of an earthquake, officials at the Wando Port terminal say they haven't experienced anything out of the ordinary.

We went looking for answers and found it actually happens all over the place all the time.

Residents in Sarasota, Florida were shaken in March by a loud noise. The unofficial cause, a space shuttle re-entering the earth's atmosphere.

Last week, it happened in Iowa, folks there are still looking for an explanation. So are a lot of people in one illinois town.

Since military aircraft are known to break the sound barrier, we called the Air Force and the Navy.

Officials we spoke with knew of no training exercises taking place, but say it is a possibility.

The National Weather Service suggests a phenomenon known as Seneca Guns, a loud boom that happens in late fall and early winter in many ocean or lakefront communities.