NGC 3987
NGC3987 is a spiral galaxy in the constellation of Leo. Its velocity with respect to the cosmic microwave background is, which corresponds to a Hubble distance of. However, 23 non-redshift measurements give a closer distance of. It was discovered by German-British astronomer William Herschel on 6 April 1785.
NGC 3987 has an active galactic nucleus, i.e. it has a compact region at the center of a galaxy that emits a significant amount of energy across the electromagnetic spectrum, with characteristics indicating that this luminosity is not produced by the stars. In addition, it is a LINER galaxy, i.e. a galaxy whose nucleus has an emission spectrum characterized by broad lines of weakly ionized atoms.
Holm 308 and NGC 3987 group
NGC 3987, NGC 3989, NGC 3993 and NGC 3997 are listed together as Holm 308 in Erik Holmberg's A Study of Double and Multiple Galaxies Together with Inquiries into some General Metagalactic Problems, published in 1937.However, according to A. M. Garcia, NGC 3987 is the largest galaxy in a group that bears its name. The NGC 3987 group is thought to have at least five galaxies, including NGC 4000, NGC 4005, NGC 4018, and NGC 4022.