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2021年10月8日 The Double Cluster in Perseus Image Credit & Copyright: Jack Groves Explanation: This pretty starfield spans about three full moons (1.5 degrees) across the heroic northern constellation of Perseus. It holds the famous pair of open star clusters, h and Chi Persei. Also cataloged as NGC 869 (top) and NGC 884, both clusters are about 7,000 ligh...
2020年11月18日 A Double Star Cluster in Perseus Image Credit & Copyright: Greg Polanski Explanation: Most star clusters are singularly impressive. Open clusters NGC 869 and NGC 884, however, could be considered doubly impressive. Also known as “h and chi Persei”, this unusual double cluster, shown above, is bright enough to be seen from a dark ...