Eyes Galaxies
The Eyes Galaxies (NGC 4435-NGC 4438, also known as Arp 120) are a pair of galaxies about 52 million light-years away in the constellation Virgo. This galaxy takes its name from its ring structure which made it popular.
NGC 4435
NGC 4435 is a barred lenticular galaxy with a relatively young (age of 190 million years) stellar population on its central regions that has been discovered by the Spitzer Space Telescope and whose origin may be the interaction with NGC 4438. It also has a long tidal tail possibly caused by the interaction with the mentioned galaxy; however other studies suggest that tail is actually a galactic cirrus in the Milky Way totally unrelated to NGC 4435.
NGC 4438
NGC 4438 is the most curious interacting galaxy in the Virgo Cluster, due to the uncertainty surrounding the energy mechanism that heats the nuclear source; this energy mechanism may be a starburst region, or a black hole powered active galactic nucleus (AGN). Both of the hypotheses are still being investigated.