ngc 4676, or the mice galaxies, are two spiral galaxies in the constellation coma berenices. about 290 million light-years away, they began the process of colliding and merging. their name refers to the long tails produced by tidal action—the relative difference between gravitational pulls on the near and far parts of each galaxy—known here as a galactic tide. it is a possibility that both galaxies, which are members of the coma cluster, have experienced collision, and will continue colliding until they coalesce.