Explore ancient mysteries and theories about alien involvement in ancient civilizations, from the Nazca lines to Puma Punku.

Originally built as early as 4000 years ago, this structure is just one of a larger network in the Salisbury Plain that ancient astronaut theorists believe are more than just ritual sites in this clip ...

The best way to find alien technosignatures is to look for ones that have long survived their creators, according to a new ...

The series will, as always, takes a look at the many ways it is possible that human development comes from a sect of magical aliens. Each episode of “Ancient Aliens: Origins” seeks to revisit the ...

The popular history docuseries Ancient Aliens: Origins returns to the History Channel with its season two premiere Monday, Oct. 6 at 8/7c. During the season two premiere episode, viewers will travel ...

New theoretical models have strengthened the case that immense, energy-harvesting structures orbiting their host stars could exist in principle in distant stellar systems. With the right engineering ...