The phrase "ancient aliens" refers to the idea that intelligent extraterrestrial beings visited and interacted with ancient civilizations on Earth in the past. Full definition
Having repaired your ship and added a warp drive, you're then free to explore the galaxy, either by visiting random stars, following a path toward the galactic core, or investigating a mysterious ancient alien race. (pcgamer.com)
If you're looking to get up to speed before saving the galaxy from ancient alien threats (as usual), here's everything you need to know about Halo 5: Guardians. (tomsguide.com)
Updated Tiny salt crystals encased in rock that fell to Earth from ancient alien worlds contain organic compounds and water vital to life, finds a new analysis that suggests how space rocks plummeting to Earth could have seeded life. (newsweek.com)