Stephans quintet

Stephan's Quintet is a group of five galaxies located in the constellation Pegasus. The group was discovered by Édouard Stephan in 1877. The galaxies in the group are NGC 7318, NGC 7318A, NGC 7318B, Arp 319, and VV 340. Stephan's Quintet is a compact group of galaxies, with the five galaxies being located within a region of space that is only about 10 million light-years across. The galaxies in the group are interacting with each other, and this interaction is causing them to undergo a variety of changes. Stephan's Quintet is a very interesting group of galaxies, and it is one of the most-studied galaxy groups in the sky.