Hickson Compact Group 31

These four dwarf galaxies waited billions of years to come together, setting off a fireworks show as thousands of new star clusters come to life. The distorted galaxies of the Hickson Compact Group 31 are quickly producing massive, hot, young stars that are pumping out ultraviolet radiation, heating up surrounding gas clouds and causing them to glow. In this composite image of the galaxy grouping, the bright, distorted object at middle left is actually two colliding dwarf galaxies. Myriad star clusters have formed in the streamers of debris pulled from the galaxies and at the site of their head-on collision. The cigar-shaped object above the galaxy duo is another member of the group. A bridge of star clusters connects the trio. A long rope of bright star clusters points to the fourth member of the group, at lower right. The bright object in the center is a foreground star. Astronomers believe the interacting galaxies will form a large elliptical galaxy in another billion years.