M 11

The open cluster M11, also known as the Wild Duck Cluster, in the constellation Scutum against the backdrop of Milky Way stars. Dark regions of interstellar dust are also visible. The cluster was discovered by the German astronomer Gottfried Kirch in 1681. Through his telescope, it appeared as a nebulous spot, and it was not until 1733 that the English clergyman and astronomer William Derham resolved it into individual stars. Charles Messier included it in his catalogue in 1764. The Wild Duck Cluster is one of the densest and most compact known clusters; it contains about 2,900 stars. The cluster's age is estimated to be 220 million years. Its diameter is nearly 20 light-years. It is located about 6,000 light-years from Earth. This cluster is the brightest object in Scutum, a small summer constellation situated between Aquila and Serpens. The entire constellation is one large cloud of Milky Way stars, bordered by dark dust lanes. This image was produced from frames captured on different nights.