Check out 5 MORE mysterious UFO sightings that just can’t be explained, in this The Proof Is Out There compilation.

"This is a detective story that can be resolved with better data," Harvard astrophysicist Avi Loeb told Newsweek.

In early 2008, residents in and around the small central Texas town of Stephenville experienced something unexplainable: UFO ...

The Pentagon on Friday released a third batch of vintage classified files related to “flying saucers” and other unidentified anomalous phenomena — better known to most Americans as unidentified flying ...

The Pentagon on Friday released a new group of documents and videos related to UFOs, or UAPs, with 72 more documents, images and recordings.

In June 1947, Kenneth Arnold saw something strange in the sky. What he saw sparked a national UFO craze-but it was far from ...

After seeing Steven Spielberg's "Disclosure Day," check out these real-life accounts of strange aerial sightings.

Pols and experts claim that there’s a long-unheard secret tape of an “Invasion of Washington” UFO briefing – and they say the ...

From the Navy’s infamous Tic-Tac encounter to thousands of recent reports, believers say some of the strangest UFOs may be hiding underwater.

Christopher Mellon, a former high-ranking official in the U.S. Defense Department, says U.S. military leaders are baffled by ...

A triangular UFO photographed over Emiliano Zapata in central Mexico has prompted multiple witness reports across nearby ...

On a dark night several decades ago, Kate Bush pulled over by the side of the road to discover a strange phenomenon in the ...