Tune in to Alien Invasion Week on History starting Monday 9/30 through Friday 10/4 for new Ancient Aliens, plus the premiere of In Search Of, new UFO Specials and More! Over 300 giant stone spheres have been found in the jungles of Costa Rica. According to legend, these were cannonballs from the ...

Tune in to Alien Invasion Week on History starting Monday 9/30 through Friday 10/4 for new Ancient Aliens, plus the premiere of In Search Of, new UFO Specials and More! Investigating how a crystal skull may hold more information than a supercomputer in this digital exclusive from Ancient Aliens. ...