Black hole
hideIn general relativity, a black hole is a region of space in which the gravitational field is so powerful that nothing, including light, can escape its pull. The black hole has a one-way surface, called an event horizon, into which objects can fall, but out of which nothing can come. It is called "black" because it absorbs all the light that hits it, reflecting nothing, just like a perfect blackbody in thermodynamics. Quantum analysis of black holes shows them to possess a temperature and Hawking radiation.
Despite its invisible interior, a black hole can reveal its presence through interaction with other matter. A black hole can be inferred by tracking the movement of a group of stars that orbit a region in space which looks empty. Alternatively, one can see gas falling into a relatively small black hole, from a companion star. This gas spirals inward, heating up to very high temperature and emitting large amounts of radiation that can be detected from earthbound and earth-orbiting telescopes. Such observations have resulted in the scientific consensus that, barring a breakdown in our understanding of nature, black holes do exist in our universe.
For more information about Black hole, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with black holes
Black Holes in Star Clusters stir up Time and Space (w/ Video)
Dec 16, 2009 |
4.7 / 5 (15) |
5
(PhysOrg.com) -- Within a decade scientists could be able to detect the merger of tens of pairs of black holes every year, according to a team of astronomers at the University of Bonn’s Argelander-Institut ...
Theorists propose a new way to shine -- and a new kind of star
Dec 14, 2009 |
4.5 / 5 (11) |
3
Dying, for stars, has just gotten more complicated. For some stellar objects, the final phase before or instead of collapsing into a black hole may be what a group of physicists is calling an electroweak star.
Search results for black holes
Studying how black holes grow
Space & Earth / Space Exploration
3 hours ago |
not rated yet |
0
Black holes are some of the most exotic objects in the universe. They are the final evolutionary stage of giant stars much larger than the sun. When these stars explode, their cores collapse down to the size ...
NASA NuSTAR Telescope Being Built at Nevis
Space & Earth / Space Exploration
7 hours ago |
5 / 5 (1) |
0
(PhysOrg.com) -- It's an unlikely place to build a NASA telescope: a leafy estate in Irvington, N.Y., that once belonged to the son of Alexander Hamilton. Inside a hangar-like building on the site, which is ...
26 operations, 13 kidneys: hope to few with little
Dec 14, 2009 |
5 / 5 (1) |
0
(AP) -- Twenty-six operations put healthy kidneys into 13 desperately ill people: Doctors in the nation's capital just performed a record-setting kidney swap, part of a pioneering effort to expand transplants ...
List of search results for black holes
