Astrophysicist Neil deGrasse Tyson, 67, explained how any alien visitor from another planet would likely look very different ...

Videos in this batch show unidentified aerial phenomena but offer few clues to existence of alien life ...

New government UFO files reveal Apollo 17 astronauts saw 'Fourth of July' like flashes and other strange phenomena during a 1972 mission to the moon.

Buzz Aldrin is quoted as having made three observations, one of which was of something with a "sizeable dimension." ...