The Harvard astrophysicist has devoted years—and thousands of interviews—to the idea that mysterious objects streaking ...

Harvard astrophysicist Avi Loeb, known for his controversial extraterrestrial theories, is now leading a new Trump ...

A rare visitor from another star system prompted SETI to hunt for alien technology, but the mysterious object appears to be a ...

Lurking at the heart of the Milky Way, Sagittarius A* (Sgr A*) is a supermassive black hole four million times the mass of ...