Object Analysis

The Pleiades (Messier 45), also known as the Seven Sisters and Subaru, is an open star cluster containing middle-aged, hot B-type stars in the north-west of the constellation Taurus. It is among the nearest star clusters to Earth and is the cluster most obvious to the naked eye in the night sky. The cluster is dominated by hot blue and luminous stars that have formed within the last 100 million years.

A faint reflection nebula surrounds the brightest stars, once thought to be leftover material from the cluster's formation. However, modern analysis shows the cluster is simply passing through an unrelated dust cloud in the interstellar medium. The interaction creates a beautiful blue nebulosity in long-exposure photographs.

The cluster contains over 1,000 statistically confirmed members, although only a handful of bright stars are visible to the unaided eye. The core radius of the cluster is about 8 light-years, and the tidal radius is about 43 light-years. It plays a significant role in mythology across vastly different cultures, from the Ancient Greeks to the Aboriginal Australians and the Maori of New Zealand.