BBC Sky at Night

Canis Major, the Big Dog

lthough it never gets high enough in the sky to rival other open clusters, (mag. +4.5, 39' x 39'), the Little Beehive Cluster, is still a marvel – a large group of 60, and is somewhat away from the haze of the horizon. To improve the appearance of this group in the city, try using a mild light-pollution filter, a ‘Skyglow' or ‘Deep Sky'-type filter. This has the effect of darkening the background a bit, but not dimming the bright cluster stars too much. One of M41's more striking features is the strongly orange-red sun near the cluster's centre.

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