Astronomers using the Wide Field Camera 3 and the Advanced Camera for Surveys on the NASA/ESA Hubble Space Telescope have captured an image of a titanic galaxy-galaxy collision called NGC 6240.
This image shows NGC 6240. Image credit: NASA / ESA / Hubble Heritage / STScI / AURA / Hubble Collaboration / A. Evans, University of Virginia / NRAO / Stony Brook University.
NGC 6240, also known as IC 4625 or UGC 10592, is a pair of merging galaxies 400 million light-years away in the constellation Ophiuchus.
The object spans 300,000 light-years and has an elongated shape with branching wisps, loops and tails.
This mess of gas, dust and stars bears more than a passing resemblance to a butterfly and, though perhaps less conventionally beautiful, a lobster.
The two galaxies of NGC 6240 began their merger process about 30 million years ago, as seen from our planet.
Gravitational interactions between the two galaxies pulled out great streamers of millions of stars that spread across hundreds of thousands of light-years.
Huge clouds of gas and dust in the two galaxies rammed together, triggering a dramatic increase in the rate of star formation and supernova explosions. This activity heated the gas to multimillion degree temperatures, making it glow in X-rays.
Recent observations with NASA’s Chandra X-ray Observatory led to the discovery of two orbiting supermassive black holes, about 3,000 light-years apart, in NGC 6240.
Over the course of the next few hundred million years, the two black holes will drift toward one another and merge to form one larger supermassive black hole.
In 2013, astronomers discovered a new supernova (SN 2013dc) in this galaxy.
