Long before Sputnik launched, something else may have already been orbiting Earth. Known as the Black Knight Satellite, this mysterious object has sparked theories of alien observation, ancient ...

We often think of ourselves as more capable than we really are. For example, according to this survey, four in five Americans consider themselves knowledgeable about the human body, but only one in ...

At least 67,800 years ago, someone placed their hand on the wall inside a limestone cave and used a reddish-brown pigment to trace the outline of a handprint. But the unknown artist didn’t stop there: ...