Europe is quietly positioning itself to attempt one of the most audacious missions in planetary exploration: a dedicated landing on Enceladus to look directly for signs of alien biology. Instead of ...

Alien spaceships are in a league of their own, though. Earth does have a force field that could make a spacecraft landing ...

The eyes of every astronomer widened this year when an interstellar traveler was discovered in our solar system. Despite some suggestions that it could be an alien spacecraft, observations from some ...