A rogue black hole has been found in the outer regions of the lenticular galaxy SDSS J141711.07+522540.8 (GJ1417+52 for short). Evidence suggests this black hole has a mass of approximately 100,000 solar masses, and was originally located in a dwarf satellite galaxy that collided and merged with a larger one. This Hubble image shows the lenticular galaxy GJ1417+52. Image credit: NASA / ESA / Hubble. Astronomers know that black holes ranging from about...