Open clusters are groups of young stars that are loosely bound together by gravity. They typically contain anywhere from a few dozen to a few thousand stars, which are all thought to have formed from the same molecular cloud at roughly the same time. Open clusters are often found in the disk of a galaxy, where the gas and dust necessary for star formation are concentrated. They are relatively young, with ages ranging from a few million to a few hundred million years. The stars in open clusters are typically more metal-rich and more diverse in age than the stars in globular clusters. One of the defining features of open clusters is their irregular shape, with the stars spread out over a region that can span several tens of light-years. The stars in open clusters are also less densely packed than those in globular clusters, which allows astronomers to study them in more detail and to observe individual stars within the cluster.

Caldwell 16
NGC 7243, or Caldwell 16, is a visually stunning open star cluster nestled in the Lacerta constellation. Notable for its ...

Caldwell 50
Caldwell 50, also NGC 2244, is an open star cluster located within the Rosette Nebula in the constellation Monoceros. The ...

Messier 29
Messier 29 is an open star cluster located in the constellation Cygnus, about 4,000 light-years away from Earth. This cluster ...

Messier 35
Messier 35 is an open star cluster situated in the constellation Gemini, discovered by Philippe Loys de Chéseaux in 1745 ...

Messier 39
Messier 39 is a beautiful open star cluster that contains dozens of bright, sparkling stars that are visible to the ...

Messier 44 – Beehive Cluster
Messier 44, also known as the Beehive Cluster, is a stunning open cluster of stars located in the constellation Cancer, ...

Messier 45 – The Pleiades
Messier 45, also known as the Pleiades, is a stunning open star cluster located in the constellation of Taurus. Its ...

NGC 2158
NGC 2158 is a globular star cluster located in the constellation Gemini, situated relatively close to the more prominent open ...

NGC 6633
NGC 6633 is a stunning open cluster with dozens of bright and colorful stars that create a beautiful celestial tapestry ...

NGC 6939
NGC 6939 is an open star cluster situated in the northern constellation of Cepheus. This celestial grouping is characterized by ...