Discovered by Lewis Swift in 1887.
IC 10 is a small irregular galaxy in the constellation Cassiopeia at a distance of approximately 2.2 million light years. IC 10's location in the plane of the Milky Way hinders detailed observations as it is heavily obscured by interstellar matter. Based on studies of Cepheid variable stars located in IC 10, the galaxy has been determined to be a member of the Local Group of galaxies. The distance between the Andromeda Galaxy (M31) and IC 10 is approximately the same as the distance between M31 and the Triangulum Galaxy (M33). This would indicate IC 10 may belong to the M31 subgroup of the Local Group of galaxies. Due to the high rate of stellar production, IC 10 is known as a starburst galaxy. It is the only known starburst galaxy in the Local Group. Currently the stellar production rate is 0.04 to 0.08 solar masses per year. At this rate, the supply of gas in IC 10 will only last a few billion years longer.