Dynamical Evolution of a Cluster Population of Galaxies
The evolution of the 55 most massive galaxies in a Virgo Cluster simulation are shown in 15 snapshots. The first 15 galaxies are the initial spherical elliptical galaxies and the remaining 40 are spirals all sorted in order of increasing mass from top to bottom. Most of the original ellipticals end up in one of two giant ellipticals at the end of the simulation. Many disks disappear inside of the giant ellipticals and merge with each other in bound pairs or small groups to form ordinary elliptical galaxies. We can use simulations like these to track the merger rate and the evolution of the morphological mix of galaxies in the cluster environment (Dubinski 1999, in prep).
Most galaxies suffer strong tidal perturbations ("harassment") as they fall in and interact with the cluster potential and each other. Tidally induced arms and warps are common especially at high redshift. Tidal forces are also strong enough to cause disks to precess noticeably.
Click here to compare galaxy appearances at a fixed redshift.
Click on an image to see the animation! After loading, the animation will play 3 times.
