Astronomers using the NASA/ESA Hubble Space Telescope have found a cluster of young blue stars surrounding a mid-sized black hole called HLX-1.
The discovery suggests that the black hole formed in the core of a now-disintegrated dwarf galaxy. The findings have important implications for understanding the evolution of supermassive black holes and galaxies.
Astronomers know how massive stars collapse to form small black holes a few times the mass of the Sun. However, it is not clear how supermassive black holes, which can have masses of millions or even billions of times the Sun’s, form in the cores of galaxies.
One idea is that supermassive black holes may build up through the merger of small and mid-sized black holes, a view supported by a new study using Hubble.