We all know the story of our solar system, which has been born with a violent event of huge size. This event is the crash between two galaxies. This crash of our galaxy and a smaller galaxy led to stars forming in the Milky Way more than 4.5 billion years ago. There’s a big galaxy and a smaller one. The smaller one is called Sagittarius, and it is 10,000 times smaller than the Milky Way.
The crash between the galaxies doesn’t really involve stars hitting each other. However, it can lead to star formation. Let us take a clear example: it can increase the amount of gas in a galaxy or lead to the alignment of gas clouds.
The reasons behind star formation
The Reuters news agency stated that the first crash between two galaxies happened more than 6 billion years ago. Ever since then, Sagittarius has found its way through the Milky Way, and it’s 100 billion stars two more times. All of these events are linked to a jump when it comes to star formation.
Researchers showed that a long period of star formation, from 6.2 billion to 4.2 billion years ago, is actually linked to the first crash of the galaxies. We got this data with the help of the European Space Agency’s Gaia space observatory. Researchers believe that two other star formation happens in correlation to the colliding galaxies, which took place 1.9 billion years ago and one billion years ago. It’s important to mention that each one of them lasted a few hundred million years.
Tomás Ruiz-Lara, an astronomer, stated that these galaxy crashes are quite different; they are not like car crashes. Parts of the Sagittarius and parts of the Milky Way intersect. However, a crash between stars might actually be very, very rare. Well, it seems that the crash changed the speed of star formation in our galaxy: “First, we have the addition of material, gas, from Sagittarius that increases the amount of gas in our galaxy to form new stars.”. Then, he continued with the fact that there is a collision between gas clouds from both of the galaxies. This also leads to star formation. Then, these crashes are the reason behind gravitation instabilities, which can also lead to star formation.