“Two Monsters, One Galaxy, and a Collision 100 Years Away!”

Most galaxies contain supermassive black holes, built up through countless mergers of less massive black holes. This means we should see galactic black holes in all forms of evolution, and occasionally see them coming together. Now, researchers think they’ve found a close pair of supermassive black holes in the galaxy Markarian 501, located about 450 million light-years away. They’re locked in their final spiral, orbiting one another every 121 days, separated by 250-540 times the Earth-Sun distance.








