Every few billion years, a momentous event occurs in the universe, an event such as the merging if two galaxies. This happens when galaxies move closer to each other and accelerate towards one another due to their mutual gravitational attraction. It is estimated that around four billion years from now, our own galaxy, the Milky Way, will drift too close to it’s nearest neighbour, the Andromeda galaxy and the two will merge into one.
In this picture, taken by the Hubble telescope, we can see two distant galaxies, known as the UGC2369 pair, in the process of intertwining and merging together. This is why they appear to be an unusual shape. It is a fascinating phenomenon, considering that each of these two galaxies is made up of millions and millions of stars and planets hung in space.
Image credit: ESA/Hubble & NASA, A. Evans