2 April 2014
This beautiful new photograph from one of the European Southern Observatory’s powerful telescopes in the Chilean desert shows a pair of galaxies slowly dancing around each other in space.
Like many things in nature, the large, glowing galaxy in the picture is beautiful, but dangerous. In fact, some scientists are referring to it as a ‘galactic bully’.
When galaxies come close enough together, like these two, we call them ‘interacting galaxies’. They aren’t interacting the way you interact with your friends – the strong pull of each galaxy’s gravity is pulling at the other galaxy.
But this isn’t a fair tug-of-war. As you can see, one galaxy is much more massive than the other. This means it has stronger gravity, and eventually it will end this friendly game by devouring the smaller galaxy!
The galaxy dominating this picture is called NGC 1316, and there are several clues that this won’t be the first time it has devoured another galaxy. For instance, it has some unusual lanes of cosmic dust crisscrossing near its centre and some clumps of unusually small star clusters. These suggest that it may have swallowed a different spiral galaxy about three billion years ago!
As a bonus, this new picture also provides a window into the distant Universe, far beyond the interacting galaxies. Most of the faint fuzzy spots in the picture are very, very distant galaxies.