The Milky Way and Andromeda Galaxy will collide in 4 billion years
The Milky Way and nearby Andromeda galaxy are on a course of frontal collision that will take place in four billion years, according to U.S. scientists who made this announcement after a systematic research using the Hubble telescope.
The fact that the two galaxies were in the path that brought them together has been known for decades but there was not enough information on the time and the type of collision. Now it becomes known that the Andromeda (M31), located 2.5 million light years away, is moving much faster than the Milky Way and will fill the space between the two galaxies.
In about four billion years the galaxies will collide, but it will take another two billion years for them to merge completely. The image of the two galaxies will change dramatically and will create an elliptical galaxy with an irregular shape.
A smaller companion galaxy, the Triangulum (M33) is also directing to the point of impact and will probably merge with the new galaxy later. Although the collision of galaxies sounds like a dramatic and exciting event, for the stars forming galaxies it probably will not mean much.
The empty space between stars is so large that even in such an inter-galactic conflict, the probability they may encounter each other is too small. This means that the Earth probably will not be endangered and will remain in the solar system, but will change the orbit around the center of the new galaxy.