Black holes are the evolutionary endpoints of stars at least 10 to 15 times as massive as the Sun. If a star that massive or larger undergoes a supernova explosion, it may leave behind a fairly massive burned out stellar remnant. With no outward forces to oppose gravitational forces, the remnant will collapse in on itself to the point of zero volume and infinite density, creating what is known as a singularity. As the density increases, the path of light rays emitted from the star are bent and eventually wrapped irrevocably around the star. Any emitted photons are trapped into an orbit by the intense gravitational field; they will never leave it. Because no light escapes after the star reaches this infinite density, it is called a black hole. But contrary to popular myth, a black hole is not a cosmic vacuum cleaner. If our Sun was suddenly replaced with a black hole of the same mass, the earth's orbit around the Sun would be unchanged.
Black Hole Hunters Set New Distance RecordLast Updated on 2010-01-28 at 16:15GARCHING, GERMANY (Jan. 28, 2010) – Astronomers using ESO’s Very Large Telescope have detected, in another galaxy, a stellar-mass black hole much farther away than any... More »
Suzaku Catches Retreat of a Black Hole's DiskLast Updated on 2009-12-10 at 11:26GREENBELT, MD (Dec. 8, 2009) – Studies of one of the galaxy's most active black-hole binaries reveal a dramatic change that will help scientists better understand how... More »
Black Hole ConfirmedLast Updated on 2009-12-02 at 09:54In 1967, an X-ray sounding rocket discovered a fantastically bright source of X-ray emission coming from the direction of the constellation of Cygnus. Named Cyg X-3, it was soon... More »
Fermi Telescope Peers Deep into MicroquasarLast Updated on 2009-12-01 at 11:07GREENBELT, MD (Dec. 1, 2009) – NASA's Fermi Gamma-ray Space Telescope has made the first unambiguous detection of high-energy gamma-rays from an enigmatic binary system... More »