Supermassive black holes can eject large stars from our galaxy

In the 2000s, astronomers saw the first star to leave our galaxy. As it turned out, there are many more such escapees. Scientists decided to find out why stars fly away from our galaxy.

Here's What We Know

At the moment there are two hypotheses that try to explain the existence of fugitive stars. The first assumes the explosion of a supernova in a double system, as a result of which the second star receives momentum and flies outside the galaxy.

The second hypothesis speaks of a dynamic ejection due to supermassive black holes or other massive objects. They tear off one star, giving the second star a momentum of motion that takes it into intergalactic space.

The team of scientists used data from the Gaia telescope to analyse the runaway stars. They identified 417 and 1,335 O- and B-type stars, respectively. The first group contained 106 fugitives, while the second group contained about a third fewer, 69 units.

As you realised, Type O has a much higher percentage of runaway stars. To be more precise, it's almost five times higher - 25.4 per cent versus 5.2 per cent. Massive outcasts appear much more frequently. Based on their findings, scientists have determined that a supernova outburst is incapable of creating enough energy to produce a runaway star.

Source: Science Alert