Messier 11 or the Wild Duck Cluster, Catalogue as NGC 6705 is an open cluster in the constellation Scutum (the shield). Discovered by a German Astronomer Gottfried Kirch in 1681 at Berlin Observatory. The cluster was appeared as nothing more than a fuzzy blob through the telescope. It wasn’t until 1733 that the blob was first resolved into separate stars by the Reverend Willian Derham of England and Chales 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 2,900 stars.
Its age has been estimated to about 250 million years. Its name derives from the brighter stars forming a triangle which could resemble a flying flock of ducks or, from other angles, one swimming duck.
Investigating open clusters is great way to test theories of stellar evolution (process by which a star changes over the course of time), as the stars form from the same initial cloud of gas and dust and are therefore very similar to one another — they all have roughly the same age, chemical composition, and are all the same distance away from Earth.
Direct comparisons between the different evolutionary stages can be made within the same cluster. In this sense, open clusters are the closest thing astronomers have to “laboratory conditions”.
Because the stars within open clusters are very loosely bound to one another, individuals are very susceptible to being ejected from the main group due to the effect of gravity from neighbouring celestial objects. NGC 6705 is already at least 250 million years old, so in a few more million years it is likely that this Wild Duck formation will disperse, and the cluster will break up and merge into its surroundings.
Image taken at Al Sadeem Observatory, July 4, 2017 by the observatory’s resident astronomer Aldrin Gabuya.