In 1958 the great extragalactic astronomer George Abell of UCLA compiled a catalog of galaxy clusters. It was extended by Abell and collaborators in 1987 and eventually contained 4,076 clusters. Abell 2256 is a rich cluster lying in Ursa Minor. It contains more than 500 members and lies about 800 million light-years away. The clusterContinue reading “Deep-Sky Dream”
The post Deep-Sky Dream appeared first on Astronomy Magazine.
