Russian space № 8 31.03.2012 Black holes (2012)

Recently, the work "Is there life inside black holes?" was published on the website of the scientific library of Cornell University, one of the leading scientific centers in the USA. Its author, Vyacheslav Ivanovich Dokuchaev, a leading researcher at the Institute for Nuclear Research of the Russian Academy of Sciences, states: stable orbits exist not only outside black holes, but also inside their gravitational field, and spacecraft or even planets of a highly developed civilization can be in orbits around a black hole.

What are black holes, how are they studied and are they dangerous for humanity?