Stars hint at an unusual hole in the sky

A massive black hole in Centauri? Reconstruction of the star-force velocities in the area around a 200 solar mass candidate

The candidate object in Centauri has an intermediate-mass black hole between 100 and 100,000 solar mass. So far, the only solid evidence of black holes in this area is detecting the waves produced by two merging black holes. One such event, seen in 2019, is thought to have produced an object of around 150 solar masses.

astrophysicists have found pictures from the Hubble Space Telescope archives which show a black hole at 8,200 times the mass of the Sun.

The team patched the images together to reconstruct the movement of more than 150,000 stars in the cluster. Hberle says most stars move the way theoretical models predict. “But then, there were some that were moving faster.” Seven stars were close to the centre of Centauri and moving too fast to be held by the cluster alone.

This suggested that the stars had been accelerated by the gravitational pull of a massive object, such as a black hole. From the stars’ velocities, it would need to be at least 8,200 solar masses, but it could weigh as much as 50,000 suns. We didn’t know if we would find it or not. “It was a little bit of a risk, and we might have found nothing.”