When galaxies collide they often stop producing new stars

When galaxies collide they often stop producing new stars.

The universe is full of galaxies with varying shapes and sizes. Typically, when two galaxies collide, the result is the formation of a single new galaxy containing stars from both former galaxies. 

In other instances, such as with the Antennae Galaxies located in the nearby constellation Corvus, the collision can lead to a phenomenon known as starburst where old stars are recycled into young stars. 

In most cases, however, this process fails to produce any new stars due to gravitational interactions which prevent any material from moving close enough together to start forming stars again.

 When two galaxies meet, the collision often halts the creation of new stars

Galaxies are made up of billions of stars and gas clouds. The gas clouds will collide with each other and the stars will often collide as well. This can often lead to a burst of new star formation. 

However, if the two galaxies are too close together when this happens, it is often impossible for any new stars to form because the gravitational pull is too strong for gases to escape the system and for a star to form in its typical manner. 

In these situations, the galaxies will eventually merge together into a single galaxy. 

 When two galaxies collide, they are often deprived of the ability to produce new stars

Galaxies have been colliding for eons and when this happens, the gas and dust contained within the galaxies is too much to form new stars at a healthy rate. 

When two galaxies collide, they are often unable to form new stars and can even stop creating stars altogether. 

The force of the collision can be so great that it destroys the star formation in both galaxies as well as the rest of the physical structure of the galaxies themselves.