Is there anything called black hole?

An artist's drawing a black hole named Cygnus X-1. It formed when a large star caved in. This black hole pulls matter from blue star beside it. Credits: NASA/CXC/M.Weiss. blackhole_2.jpg. An artist's drawing shows the current view of the Milky Way galaxy. read more

Black holes have been inferred by observing the furious whirlpool motion of trapped gas and estimating how much mass is crammed into the tiny region of space the black hole occupies. Also, previous X-ray observations have offered evidence for an event horizon by surveying black hole candidates that seem to be swallowing nearly a hundred times as much energy as they radiate. read more

There is no “black hole theory”. Black holes are predictions of a theory, namely general relativity. read more

The largest supermassive black hole in the Milky Way's vicinity appears to be that of M87, at a mass of (6.4 ± 0.5) × 10 9 (c. 6.4 billion) M ☉ at a distance of 53.5 million light-years. read more