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A '''black hole''' is a theoretical prediction of the [[theory of relativity]].  It is impossible to prove that a black hole does not exist, and thus it fails the [[falsifiability]] requirement of science.  Nevertheless, the theoretical black hole remains a popular topic for magazines, the science page of the [[New York Times]], and scientists on the cutting edge of astronomy and cosmology, as well as being a popular device in sci-fi due to its inherent "coolness factor".

A '''black hole''' is a theoretical prediction of the [[theory of relativity]].  It is impossible to prove that a black hole does not exist, and thus it fails the [[falsifiability]] requirement of science.  Nevertheless, the theoretical black hole remains a popular topic for magazines, the science page of the [[New York Times]], and scientists on the cutting edge of astronomy and cosmology, as well as being a popular device in sci-fi due to its inherent "coolness factor".

Support and interest in black holes has grown over time.  [[Albert Einstein]] and [[Arthur Eddington]], the two most prominent scientists associated with the [[theory of relativity]], rejected the suggestion that black holes exist.<ref>http://amazing-space.stsci.edu/resources/explorations/blackholes/lesson/whatisit/history.html</ref>  Today black holes are frequently depicted on the covers of science magazines.

Support and interest in black holes has grown over time.  [[Albert Einstein]] and [[Arthur Eddington]], the two most prominent scientists associated with the [[theory of relativity]], rejected the suggestion that black holes exist.<ref>http://amazing-space.stsci.edu/resources/explorations/blackholes/lesson/whatisit/history.html</ref>  Today black holes are frequently depicted on the covers of science magazines.

 

==Nature of a Black Hole==

==Nature of a Black Hole==

A '''Black Hole''' is a theoretical mass with an infinitesimal volume, and therefore an infinite density. This gives them an escape velocity greater than the speed of light, meaning that light cannot escape from them due to their steep “gravity wells.”  As this renders black holes invisible by traditional means of observation, scientists discover their locations through indirect means, such as the effect of their gravitational pull on nearby stars. Stars that are near black holes, e.g. by being part of a binary star system that contains one, show wobbles in their orbits similar to the tidal effects of the moon on Earth’s oceans. <ref>http://library.thinkquest.org/C007571/english/advance/english.htm</ref><ref>''Black Holes'' by Heather Cooper and Nigel Henbest (book)</ref> While matter and energy, even light, may not escape a black hole, Stephen Hawking has shown that they should emit Hawking radiation, which absent of an influx of mass-energy would lead to the evaporation of the black hole in a burst of gamma rays. Scientists are currently working to pick up one of these bursts, or the radiation itself, with any of several land- and space-based telescopes. However, the matter falling into black holes as well as the cosmic microwave background from the Big Bang obscures the radiation and inhibits its detection. The outer surface of a black hole is an [[event horizon]], a non-material dimensional boundary, beyond which nothing can escape. The center of a black hole, where the mass exists, is called the singularity. The distance from the singularity to the event horizon is known as the Schwarzschild radius. All matter that falls into a black hole becomes part of the singularity, and as such is effectively destroyed.

A '''Black Hole''' is a theoretical mass with an infinitesimal volume, and therefore an infinite density. This gives them an escape velocity greater than the speed of light, meaning that light cannot escape from them due to their steep “gravity wells.”  As this renders black holes invisible by traditional means of observation, scientists discover their locations through indirect means, such as the effect of their gravitational pull on nearby stars. Stars that are near black holes, e.g. by being part of a binary star system that contains one, show wobbles in their orbits similar to the tidal effects of the moon on Earth’s oceans. <ref>http://library.thinkquest.org/C007571/english/advance/english.htm</ref><ref>''Black Holes'' by Heather Cooper and Nigel Henbest (book)</ref> While matter and energy, even light, may not escape a black hole, Stephen Hawking has shown that they should emit Hawking radiation, which absent of an influx of mass-energy would lead to the evaporation of the black hole in a burst of gamma rays. Scientists are currently working to pick up one of these bursts, or the radiation itself, with any of several land- and space-based telescopes. However, the matter falling into black holes as well as the cosmic microwave background from the Big Bang obscures the radiation and inhibits its detection. The outer surface of a black hole is an [[event horizon]], a non-material dimensional boundary, beyond which nothing can escape. The center of a black hole, where the mass exists, is called the singularity. The distance from the singularity to the event horizon is known as the Schwarzschild radius. All matter that falls into a black hole becomes part of the singularity, and as such is effectively destroyed.