Three supermassive black holes on a collision course
For the first time ever, astronomers have discovered a system of three supermassive black holes orbiting each other. The discovery was made after observations from several telescopes that operate in different parts of the light spectrum.
Scientists from George Mason University in the US were searching for pairs of black holes that orbit each other. But then they spotted this rare trio located around a billion light years away. The discovery was made by the SDSS optical telescope, and was subsequently confirmed by the infrared WISE telescope and the Chandra X-ray telescope.
Observations of the three black holes might solve a theoretical paradox involving black holes that merge. Two black holes will rotate ever closer to each other without meeting, because each one loses energy to stars and other passing matter. As a star passes by, it is supplied with energy and ejected at a higher speed, with the black holes losing the same quantity of kinetic energy. The loss makes the two black holes approach each other slightly, but the effect subsides when the distance between the two black holes reaches a few light years, and so they should never merge. Yet gravity wave data has shown that this does, in fact, happen.
According to scientists, this might be explained by the presence of a third, heavy object. Calculations have shown that three black holes in orbit approach each other much faster than if there are only two.