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NGC 6811 - THE HOLE IN THE CLUSTER on 2023-06-30_58 subs x 30 sec

NGC 6811 is an open cluster of about 1,000 stars in the constellation of Cygnus, near the constellation of Lyra. From Earth it's angular size appears to be about half the size of the full Moon. It has been called "The Hole in the Cluster" because of its dark center. NGC 6811 is located far outside the galactic plane, a feature it shares with many other old open clusters. It's distance is about 3,285 light years from the Earth and it's diameter is about 14 to 20 light years. It's actual brightness is equal to the total luminosity of  2,100 suns. Astronomers have found 377 confirmed stars within the cluster that have surface temperatures relatively similar to our Sun's.