An international team of scientists has discovered a double black hole

An international team of scientists has gained new evidence that a double black hole exists in galaxy OJ 287.

Fortunately, this system of black holes does not threaten earthlings because galaxy OJ 287 is located five hundred billion light-years from Earth.

Two supermassive black holes are situated in OJ 287 galaxy's center. Scientists could establish that one of the black holes orbits around the other and even pierces the accretion disk of an even bigger massive black hole which happens twice every twelve years. The supermassive double black hole that reveals such close interaction is currently the only one in the Universe known to humankind.

The long-baseline radio interferometry (VLBI) system discovered the double black hole. The idea was suggested back in the mid-1960s by Soviet scientists N. Kardashev, L. Matveenko, and G. Sholomitsky.

It is a technology that allows high-resolution photographs of a space object by synchronizing two telescopes. For example, without the VLBI system, images of a black hole at this resolution would only be possible by using a telescope the size of our planet.