Will the Milky Way collide with M31 and what’s the outcome?
Every second, the Andromeda Galaxy (also known as M31) travels 110 kilometers towards us. In one minute, that’s 6,705 kilometers. In less than 10 minutes, you can go around the whole Earth at that speed. That’s a lot of speed.
However, for our galaxy and M 31 to meet, it will take much longer, even 3.9 billion years, because the distance between the two galaxies is also large. It is 2.5 million light years.
Of course, the imaginary residents of the M31 galaxy see our galaxy approaching them.
In any case, the collision of the Milky Way and M31 is inevitable.
Galaxy collisions are very interesting. The galaxies simply pass through each other, separate, but their gravities don’t allow them to go very far, and they will begin to converge again until another collision, which in the case of M31 and the Milky Way will be an event in 5.1 billion years.
In any case, and we talked about this as well, collisions of galaxies are mostly collisions of empty space. It is almost impossible for two stars to meet at all in such a single event because the interstellar distances are enormous.
Let’s say you have a glass marble with a diameter of one centimeter and another marble 1000 kilometers away. If you fire them at each other – what are the chances that they will collide?
And so, it is with the stars. But dramatic changes will certainly occur and they will be a consequence of the gravity of the two galaxies. The galaxies will eventually merge but both will lose shape. It will be a huge, irregular cluster of trillions of stars.
And what will happen to the Solar system in that colossal collision?
The most reliable answer would be: we have no idea?!
And really, there is no way to say anything precisely, but still some estimates exist.
First of all, you should know that at that time, according to the laws of its evolution, the Sun will have long since become a red giant that will swallow all the planets up to the Earth.
It will swell so much that it will cover space up to Earth. It is not yet entirely clear whether the Earth will also be swallowed then, but it is certain that it will be overheated, scalded, without a drop of water and there will be no life on it.
There is, astronomers say, a 50% chance that the solar system will be ejected to the outskirts of the new, merged galaxy. There are slightly less chances (some 12% say) that the solar system will be pushed even further, even into intergalactic space.
So, according to this scenario, the solar system would survive the collision without any harmful consequences and would continue to exist and only its sky would change.
It would become very dark, almost starless with only a few distant galaxies – only then would there be no one to notice.
Another galaxy, the third largest in the Local Cluster, will somehow be involved in the whole event. It is the Tiangulum galaxy or M33.
After the merger of the Milky Way and M 31 Triangulim they will orbit around the new, merged galaxy for a while and become its satellite galaxy, only to be swallowed up sooner or later.
