Pleiades Star Cluster – also known as the Seven Sisters and Messier 45, are an open star cluster containing middle-aged stars in the north-west of the constellation Taurus. It is among the star clusters nearest to Earth, the star cluster most obvious to the naked eye in the night sky.
The focal point are the seven luminous stars that have formed within the last 100 million years. Reflection nebulae around the brightest stars were once thought to be left over material from the formation of the cluster, but are now considered likely to be an unrelated dust cloud in the interstellar medium through which the stars are currently Passing.