Ancient Aliens is an American television series that premiered on April 20, 2010, on the History channel. Produced by Prometheus Entertainment in a documentary style, the program presents hypotheses of ancient astronauts and proposes that historical texts, archaeology, and legends contain evidence of past human-extraterrestrial contact.The show has been widely criticized by historians, cosmologists and other scientific circles for presenting and promoting pseudoscience and pseudohistory.

The series started with a TV special of the same name that aired on March 8, 2009, on the History channel. Seasons 1–3 aired on the same channel until 2011. From season 4 to the middle of season 7, the series aired on H2. On April 10, 2015, episode premieres returned to History.