Distance: 300,000,000 light-years
Arp 81 consists of two strongly interacting galaxies about 100 million years after their closest approach.
The galaxy on the left is designated NGC 6621 and the right galaxy is NGC 6622. The larger galaxy on the right is greatly gravitationally disturbed by the encounter.
A long tail of stars was pulled out of NGC 6622 and extends around and behind both galaxies. Extensive star formation was triggered between the two galaxies resulting in a rich collection of young massive star clusters.
Arp 81 lies in the constellation of Draco and is approximately 300 million light-years from the Earth.