In the picture you have the NGC 4631 galaxy known as the Whale and located about 30 million light years. Named for its shape (which, despite being a spiral galaxy like ours), the curious and remarkable of this galaxy are his two companions (NGC 4627, NGC 4656).
If you look at the image above, near the yellow circle is the first of the two (NGC 4627) believed that his attraction had aberree gavitatória the shape of the whale galaxy and given its shape. Fortunately, later we have seen that other (NGC 4656) and just under practically absorbed by a collision between galaxies. In fact, they are arms (below left) dust ejected by the impact, known as outbreaks of which can only be seen in one image having a total of four. It is thought that the beginning of the crash was 4 billion years ago, and yet, the process continues.
The central region of this galaxy, filled to the feet of hydrogen, is a high-creation of star fruit crash earlier galaxies (and the force of gravity, remember). Apart from being a very important area of creating solar wind.