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Double Cluster (h and Chi Persei; NGC 869 and NGC 884)

Double Cluster
Double Cluster.
Image credit: Michael Fullbright (

Two young open clusters that lie close together in the sky in Perseus and are visible to the naked eye on a clear, dark night as a hazy patch of light. Both clusters lie in the Perseus OB1 Association and contain many B stars and M supergiants.

visual magnitude 4.3 (h), 4.4 (Chi)
age (millions of years) 5.6 (h), 3.2 (Chi)
distance (light-years) 7,100 (h), 7,400 (Chi)

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