The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

MSNBC’s Lawrence O’Donnell explains that for the first time in presidential history, instead of offering sympathy, Donald ...

It took two years for NASA's OSIRIS-REx space probe to return from asteroid Bennu before dropping off a small capsule as it flew past Earth, which was ...

With the OSIRIS-REx space probe, the NASA space agency succeeded in collecting some material from the surface of asteroid ...