Black holes are one of the most mysterious objects in the Universe. The theoretical possibility of their existence followed from some equations of Albert Einstein, but disputes on reality of this phenomenon were conducted for many years. Nevertheless, as a result black holes were not only are found, but also weighed".
Black hole call area in space time with very big gravitation, it even photons cannot quit the world. As this area releases nothing outside, it cannot be seen, about existence of a black hole it is possible to judge only by the indignations brought by it in surrounding space. Passing by some star, the black hole in literal sense breaks off it on a part. Observation of the similar phenomena also allows scientists to define location of a black hole.
At a rupture of a star a black hole residues of star substance disperse to big speeds that leads to emergence of various study including registered by radio telescopes. Scientists managed to analyze radiation from flash of a star of Swift J1644+57 recorded in March, 2011. It was the most powerful of the being registered flashes of this sort. The initial reason of its emergence considered flash of a supernova, but soon refused this assumption. Explosions of supernew fade in several days whereas in this case radiation proceeded several months. The substance of the star absorbed by a black hole warmed to high temperatures was its source.
It was established that radiation changes with a frequency of 200 seconds, it was explained with rotation of the involved star substance around a black hole. Based on characteristics of radiation, researchers could calculate the approximate mass of a black hole – from 450 thousand to 5 million mass of the Sun. Such indicators quite correspond to supermassive black holes which are present at the center of the majority of galaxies. It is still impossible to calculate weight more precisely as scientists should be based on indirect indicators. It is not the first black hole which mass managed to be calculated. So, in July, 2012 the researchers could calculate the mass of a black hole of HLX-1, it appeared around from 9 to 90 thousand solar masses. It should be noted that the splash in radiation which is formed at destruction of a star a black hole has enormous power and can be very dangerous. For example, the intensity of x-ray radiation from matter which is sucked in by a black hole of HLX-1 exceeds intensity of solar radiation in 260 million times. If Earth gets to the central beam of such radiation, life on our planet completely will stop.