Sputnik skies to analysis of interstellar visitors, scientists are rethinking how and where to look for physical traces of ...

SETI@home has been one of the largest citizen science projects ever, with millions of users around the world.

For as long as humans have looked up at the night sky, we've wondered who, or what, might be looking back. From ancient myths about gods descending from the heavens to 20th-century UFO sightings and ...