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Two odd couples

A pair of star clusters will intrigue careful observers.
RELATED TOPICS: STARS | OPEN CLUSTERS
OMearaStephen
T  he Double Cluster (NGC 869 and NGC 884) in the constellation Perseus is the night sky’s best example of an open star cluster pairing. It’s also one of the most striking sights through backyard telescopes. These two roughly 5th-magnitude clusters — each a dazzling citadel of crystal starlight — span two Moon diameters in apparent extent and are separated by a mere 25'.

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