Mass merger of galaxies
http://rberring.iweb.bsu.edu/animatio...
This movie is a 160 thousand particle simulation of two galaxy clusters, each with fifty galaxies, on a collision course. This simulation was presented in the paper Berrington & Dermer ApJ, 2003, 594, 709. The galaxy particles (both luminous and dark matter particles) are shown in white. The cluster wide dark matter is shown by the transparent orange particles.