Black Holes (Astronomy) - Term Paper Example

This means that the general perception that if the sun runs out of its nuclear fuel and is turned into a black hole it will suck the Earth into it, is wrong (Novikov). A region of influence surrounds a black hole from where any mass or light cannot escape. At the boundary of this region light starts leaving the black hole thus the escape velocity from the gravitational field of the black hole at this point becomes equal to the speed of light. The set of such points surrounding the black hole where the escape velocity becomes equal to the speed of light forms a curved boundary which is known as event horizon.

The calculation of the distance of event horizon from the centre of a black hole is a simple process if the black hole is uncharged and stationary, however in case of a charged and rotating black hole; the calculations involve very complex equations of particle physics. For a simple non-rotating and uncharged black hole, the radius of the event horizon is found to be directly proportional to the mass of the black hole and inversely proportional to the square of the speed of light. The effective mass of a black hole is the entire mass contained inside the boundaries of event horizon (Raine and Thomas).

Black holes are of various different types the most common of which is stellar mass black holes which have masses up to 10 to 15 times of the mass of sun. The stellar mass black holes are formed when a star runs out of its nuclear fuel. A huge supernova explosion supersedes the formation of a black hole. The explosion results in the formation of a black core at the place where the parent star of the black hole existed. The boundary of the mass of the star only defines the core of black hole and after the formation of the black hole its influence extends up to the event horizon.

Some of the black holes are present in the core of the galaxies and are of gigantic sizes ranging from