武仙星系团
2020年11月7日 The Hercules Cluster of Galaxies Image Credit & Copyright: Howard Trottier Explanation: These are galaxies of the Hercules Cluster, an archipelago of island universes a mere 500 million light-years away. Also known as Abell 2151, this cluster is loaded with gas and dust rich, star-forming spiral galaxies but has relatively few elliptical gala...