Galaxy merger
Videos
Galaxy mergers can occur when two galaxies collide. They are the most violent type of galaxy interaction. The gravitational interactions between galaxies and the friction between the gas and dust have
The Mice Galaxies (NGC 4676 A&B) are in the process of merging.
NGC 3921 is an interacting pair of disc galaxies in the late stages of its merger.
ESO 239-2, an interacting pair of galaxies located 550 million light-years in the constellation of Grus. These galaxies are currently in the last stages of merging which the end result would be an elliptical galaxy.
SDSSCGB 10389, a trio of galaxies merging into a single object
Spiral galaxy
Videos
Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work The Realm of the Nebulae and, as such, form part of the Hubble sequence. Most spiral galaxies consist of a
An example of a spiral galaxy, Messier 77 (also known as NGC 1068)
Tuning-fork-style diagram of the Hubble sequence
Barred spiral galaxy UGC 12158
NGC 1300 in infrared light