On Monday night, a mysterious radar blip appeared over southern Illinois and western Kentucky. It lingered for over 10 hours, having traveled for nearly 140 miles before disappearing. The National Weather Service was stunned – the blips resembled a moving storm, but it wasn’t even raining.

The internet was quickly on the case, with social media users sharing their theories. Some suggested that the blips may have been a result of debris from a passing meteor, a simple flock of birds, chemical residue from government weather control, and even aliens.

An Indiana meteorologist tweeted that a pilot claims the mystery was no mystery at all and could be explained by radar-jamming material being released by a Lockheed C-130 Hercules aircraft.

While the mysterious blips may have been a result of military aircraft, all nearby military bases contend that they didn’t have anything to do with it.

“Whatever aircraft it was, it was not a Scott Air Force Base craft,” Master Sgt. Thomas Doscher said Tuesday. Scott Air Force Base is located in Illinois, east of St. Louis, MO.

A spokesperson for Fort Campbell, located in Kentucky, was not aware of any operation involving a C-130 during the time the mysterious blip appeared on radar. He added, however, that if a plane were involved, it would have been due to a secret special forces exercise.

The War Zone says that the blip was indeed a result of chaff from a C-130 returning home at McLaughlin Air National Guard Base in Charleston after a training exercise on the West Coast.

The National Weather Service later tweeted in support of this theory.

According to the Washington Post, “Chaff is a cloud of light aluminum-coated material deployed in the air to fool and overwhelm radar signals that may be tracking the aircraft.” Apparently, for safety reasons, the plane needed to dump it from its countermeasure dispensers before landing.

Now, two days after the incident over Illinois, Indiana and Kentucky, more plumes of chaff are appearing on radar over both Maine and Florida. While the source of these newest reports remain unconfirmed, they appear quite similar to Monday’s incident.

While the appearance of chaff on radar is not particularly rare in itself, it is unusual for so many persistent clouds of this size to appear on radar in such a short period of time in so many places across the country.