NGC 185とは 意味・読み方・使い方

NGC 185 (also known as Caldwell 18) is a dwarf spheroidal galaxy about 2.08 million light-years away in the constellation Cassiopeia. It is a member of the Local group, and is a satellite galaxy of the Andromeda Galaxy (M31). NGC 185 was discovered by William Herschel on November 30, 1787, and he cataloged it "H II.707". John Herschel observed the object again in 1833 when he cataloged it as "h 35", and then in 1890 when he cataloged it as "GC 90" within his General Catalogue of Nebulae and Clusters. NGC 185 was first photographed between 1898 and 1900 by James Edward Keeler with the Crossley Reflector of Lick Observatory. Unlike most dwarf elliptical galaxies, NGC 185 contains young stellar clusters, and star formation proceeded at a low rate until the recent past. NGC 185 has an active galactic nucleus (AGN) and is classified as a type 2 Seyfert galaxy.