Two galaxies are colliding 430 million light years away. The unusual shape of the large spiral galaxy is due to its collision with a smaller bluish galaxy, seen near the nucleus (upper left part). As with the Antennae galaxies, gravitational forces have created the long, tadpole-like tail of stars and interstellar material and triggered the formation of the huge blue star clusters, massive enough to become small, self-gravitating galaxies or globular clusters. This 2002 optical image of Galaxy UGC 10214 comes from the Hubble Space Telescope's Advanced Camer for Surveys.