The solar system has many more moons than the one we can see in the sky. But how many do we actually know about? And how many ...

Avi Loeb said bases this hypothesis on a July 21 image captured by the Hubble Space Telescope and shared by NASA.

Wow”, scribbled Jerry Ehman, encircling the mysterious 72-second burst from the stars, a signal so sharp and unearthly that ...