Coma star cluster

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Observation data (J2000 epoch)
Coma Star Cluster
Melotte 111, taken from a rural location in Derbyshire, England in March 2003.
Constellation	Coma Berenices
Right ascension	12^h 22.5^m^[1]
Declination	+25° 51′^[1]
Distance	288 ly^{[citation needed]} (88.3 pc)
Apparent dimensions (V)	5°^{[citation needed]}
Other designations	Melotte 111,^[1] Coma Ber Cluster,^[1] OCl 558.0^[1]
See also: Open cluster, List of open clusters

Not to be confused with the Coma cluster of galaxies.

The Coma Star Cluster in Coma Berenices, designated Melotte 111 after its entry in the catalogue of deep sky objects by P. J. Melotte, is a small but nearby star cluster in our galaxy, containing about 40 stars (magnitude 5 to 10) with a common proper motion. It used to be known to represent Leo's tail, but Ptolemy III, in around 240 BC, renamed it for the Egyptian queen Berenice's sacrifice of her hair in a legend. The open cluster has a distance of 288 light-years - roughly twice as distant as the Hyades - and covers an area of more than 5 degrees on the sky. The cluster is approximately 450 million years old. In the FOV of a good field glass most of its stars can be seen simultaneously. It is situated in the constellation Virgo.

Shown are 2 images of Melotte 111, taken from a rural location in Derbyshire, England in March 2003, exposed for about 30 seconds with a normal film camera. The brighter stars of the cluster make out a distinctive "V" shape as seen when Coma Berenices is rising. The slightly orange background is caused by light pollution coming from nearby cities. The below image is the same photo with labels added. The position of Gamma Coma Berenices is shown, as are the constellation outlines (orange), constellation boundaries (blue), and lines of equal right ascension and declination (green).