If you're a skeptic, these UFO sightings will convince you that the truth is out there—and it may not be from Earth.

A 1948 secret military report and reports of UFO activity at nuclear missile sites suggest a history of government concealment regarding unidentified flying objects.

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

Tennessee Congressman Tim Burchett claims American military pilots and service members who witnessed UFOs have destroyed video ...

NASA's relationship with UFOs has evolved alongside broader changes in public and government interest in unexplained sightings.

National attention on UFOs has shifted in recent years, especially after the US government in the past decade has released reports about them.

Avi Loeb, a Harvard astronomer who has made headlines with his theories about alien encounters, will lead a White House scientific advisory council on UFOs.