27th January 2010.
Astronomers using the ESO Very Large Telescope have found a black hole called NGC300 X-1 in the spiral galaxy NGC 300 in the constellation Sculptor. This is the furthest stellar mass black hole yet found. Stellar Mass black holes have a mass up to 20 times that of the Sun, and are much less massive than super massive black holes at the centres of galaxies. It lies at a distance of 6 million light years away, which puts it further out than own local group of galaxies.
The star the black hole is orbiting is a Wolf-Rayet star, which is itself about 20 times the mass of our Sun. Wolf-Rayets are extremely hot stars nearing the end of their lives, and lose large amount of material into space from stellar winds that can travel at up to 2,000 kilometres per second. In less than one million years this star will eventually explode in a supernova and become a black hole itself, creating a black hole pair that will over a few billion years merge into one.
Artist's impression of black hole NGC300 X-1 in orbit around it's Wolf-Rayet star.
The Wolf-Rayet star and it’s super dense companion orbit each other every 32 hours, as the star gets stripped of it’s material by the black hole.
