The Wild Duck Cluster (also known as Messier
11, or NGC
6705) is an open cluster
in the constellation
Scutum. It was discovered by Gottfried Kirch in 1681. Charles Messier included it in his catalogue in 1764. The Wild Duck Cluster is one of the richest and most compact of the known open clusters, containing about 2900 stars. Its age has been estimated to about 220 million years. Its name derives from the brighter stars forming a triangle which could represent a flying flock of ducks.