Black holes are absolutely fascinating phenomena which are basically a region of space-time in which not even light can escape, let alone anything else. General relativity dictates that sufficiently compact mass will deform space-time and create a black hole as a result. An event horizon is the surface around a black hole which no matter can ever return from, even the light emitted by a Gu 10 light bulb! The reason behind the term “black” hole is that the hole absorbs all light that hits this surface and reflects nothing whatsoever. A black hole can thus be understood as a perfect black body. Black holes emit radiation, or so quantum mechanics dictate. John Michell and Pierre-Simon Laplace first considered the concept of an object whose gravity field might be so strong that not even light can escape. Michell and Laplace speculated over this notion in the eighteenth century.

One can truly trace the roots of the theory of black holes to Karl Schwarzschild. Schwarzschild developed the very first modern of general relativity which would characterize a black hole. Schwarzschild developed the theory in 1916. It was not until the 1960s however that theoretical work indicated that black holes were as prediction of general relativity. The notion that black holes could be an astrophysical reality did not occur until neutron stars were discovered which sparked interest in gravitationally collapsed compact objects. When massive stars collapse at the end of their lives, black holes of stellar mass are understood to form. Black holes can continue to grown after they have formed through the absorption of mass from their surroundings.