Inside the Tycho crater, one of the Moon’s biggest craters and found in the southern hemisphere, conspiracy theorists believe they have spotted a strange structure. Alien hunters have been prowling ...

When sonar first picked up a massive, stair‑like object on the floor of the Baltic Sea, the image looked less like geology and more like a movie prop. The structure’s circular outline, sharp edges and ...

One night about 60 years ago, physicist Enrico Fermi looked up into the sky and asked, "Where is everybody?" He was talking about aliens. Today, scientists know that there are millions, perhaps ...