In a recently shared NASA image, an appearance of a galaxy called NGC 6240 contains two supermassive black holes in the process of fusion. The image consists of new X-ray data from Chandra (shown in red, orange and yellow), which were combined with an optical image from the Hubble Space Telescope originally released in 2008.
These fused black holes are about 3000 light-years away and are seen as the bright point-like sources in the middle of the image. These black holes are as close as they turn to each other – a process that began about 30 million years ago.
In 2020, based on Chandra data, the discovery of two fusing black holes was announced. Since 2002, there has been intense interest in subsequent observations of NGC 6240 by Chandra and other telescopes.
NGC 6240 is a nearby ultralight infrared galaxy (ULIRG) in the constellation Ofipho. The galaxy is the remnant of a merger between three smaller galaxies.
According to scientists, the fusion process may have begun about 30 million years ago. It is estimated that the two black holes will eventually drift together and merge into a larger black hole after a few tens or hundreds of millions of years.
It is assumed that pairs of massive black holes may explain some of the unusual behavior seen by rapidly growing supermassive black holes, such as the distortion and bending seen in the power jets they produce. Also, pairs of massive black holes in the fusion process are expected to be the most powerful sources of gravitational waves in the Universe.