NGC 4318  NGC 4318 is a small lenticular galaxy located about 72 million light-years away in the constellation Virgo. It was discovered by astronomer John Herschel on January 18, 1828. NGC 4318 is a member of the Virgo W′ group, a group of galaxies in the background of the Virgo Cluster that is centered on the giant elliptical galaxy NGC 4365. NGC 4318 contains a small, classical bulge and a nuclear stellar disc with a diameter of ~. Outside the nuclear stellar disc lies a sharply bounded, low surface brightness region with a diameter of ~ beyond which lies a larger outer disk. NGC 4318 harbors a supermassive black hole with an estimated mass of 4 million ( M☉) solar masses. NGC 4318 is surrounded by 18 globular clusters.