Space + Flight

20
Mar

Talk About Centripetal Force

Phil Plait, at Bad Astronomy:

A black hole was recently discovered that has a star orbiting it at an incredible two million kilometers per hour (1.2 million mph). Even though the star is about million kilometers (600,000 miles) away from the black hole—a little more than twice the distance of the Earth to the Moon—it screams around its orbit in just 2.4 hours.