M11, the "Wild Duck Cluster", is one of the richest galactic star clusters, as it includes about 2.900 stars, about 500 of which are brighter than magnitude 14. It is located at the edge of the dense Scutum Star Cloud in the Summer Milkyway. Its diameter measures about 14 arcminutes. The age of M11 has been estimated to about 250 million years, as its brightest and hottest main sequence stars are of spectral type B8. The cluster is receding at 22 km/sec.

M11 was discovered visually by the German astronomer Gottfried Kirch at the Berlin observatory in 1681.

The Summer Milkyway and Mars, standard-lens photograph.
M11 - Wild Duck Cluster, Newtonian photograph.