14 DAY TRIAL // Open star clusters are among the most important tools for the study of stellar and galactic evolution. The Pleiades are one of these clusters, a young and bright one, dominated by hot blue stars, which have formed within the last 100 million years.
The Pleiades' high visibility in the night sky has guaranteed it a special place in many cultures, both ancient and modern. In Greek mythology, they represented the Seven Sisters, while to the Vikings, they were Freyja's hens, and their name in many old European languages compares them to a hen with chicks.
The cluster is located at a distance of about 135 parsecs and has large amounts of interstellar gas that forms faint reflection nebulosity around the brightest stars, which is believed to be an unrelated dust cloud that the stars are currently passing through.
In addition to the bright, visible star, the Pleiades also contain dwarfs, or "failed stars" and disks of planetary debris, which are much fainter when viewed in optical light. Being about 12 light years in diameter, it reportedly contains approximately 500 stars in total, and the total mass of the cluster is estimated to be about 800 solar masses.
The nine brightest stars of the Pleiades are named for the Seven Sisters of Greek mythology: Sterope, Merope, Electra, Maia, Taygete, Celaeno and Alcyone, along with their parents Atlas and Pleione.
On Earth, the Pleiades are the symbol of the Japanese car manufacturer, Subaru, which literally translates as "the Pleiades" and whose logo incorporates six stars.
It is the most famous star cluster on the sky that can be seen without binoculars from even the depths of a light-polluted city.
According to new calculations published by a team from Geneva the age of the Pleiades star cluster amounts 100 million years. It has been calculated that the Pleiades have an expected future lifetime as a cluster of only about another 250 million years.