Located 300 million light-years away in the constellation Coma Berenices, these two colliding galaxies were captured by the Advanced Camera for Surveys (ACS), onboard the NASA/ESA Hubble Space Telescope in 2002.
The Mice Galaxies (which are also known as NGC 4676) are a pair of interacting galaxies. The galaxies have been nicknamed “The Mice” because of the long tails of stars and gas emanating from each galaxy. Otherwise known as NGC 4676, their name refers to the long tails produced by tidal action, which is the relative difference between gravitational pulls on the near and far parts of each galaxy.
The process of colliding and merging began about 290 million years ago. Because the distances are so large, the cosmic interaction takes place in slow motion — over hundreds of millions of years. The pair will eventually merge into a single giant spherical galaxy (known as an elliptical galaxy). The stars, gas, and luminous clumps of stars in the tidal tails will either fall back into the merged galaxies or orbit in the halo of the newly formed elliptical galaxy.