A study of more than 20,000 merging galaxies claims that when two different sized galaxies collide, the larger galaxy stops the smaller one from making new stars.
The research also found that when two galaxies of the same size collide, both galaxies produce stars at a much faster rate.
Astrophysicist Luke Davies claims that the Milky Way’s nearest major galactic neighbour, Andromeda, is hurtling on a collision course at about 400,000 kilometres per hour but they won’t smash into each other for another four billion years.
Previously, astronomers thought that when two galaxies smash into each other, their gas clouds get churned up and seed the birth of new stars much faster than if they remained separate.
But Davies claims that whether a galaxy forms stars more rapidly in a collision or forms any new stars at all that depends on if it is the ‘big guy’ or the ‘little guy’ in this galactic ‘car crash’.
Talking about the Milky Way’s collision with Andromeda, he added that as they get closer together, they will begin to affect each other’s star formation, and will continue to do so until they eventually merge to become a new galaxy.
The study is published in the Journal Monthly Notices of the Royal Astronomical Society.