If ancient extraterrestrial explorers ever traipsed through Earth's cosmic neighborhood, it's possible they left behind some interstellar litter in their wake. Think of it like the loose hubcaps on ...

A new study proposes searching the moon for remnants of ancient extraterrestrial technology. Researchers suggest the moon's surface could preserve microscopic "technosignatures" left by alien ...

Claims have emerged that NASA pilots were told to destroy photos that may have contained images of UFOs, as other astronauts ...