« back to overview Star Clusters
« back to overview nebula
Load higher resolution (1800 x 1200 Pixel    3500 x 2300 Pixel) Object description
Messier 45 - the Pleiades in the constellation Taurus in a wide-angle view

Description of object:

The Pleiades - also called the Atlantiads, the Atlantiads and the Seven Sisters - is an open star cluster, already visible with the naked eye in the constellation of Taurus. In the Messier catalogue it is called M 45, named after the Pleiades from Greek mythology.

The 7 brightest stars are named after figures from Greek mythology, the Titan Atlas (hence Atlantides), his wife Pleione and their seven daughters Alkyone, Asterope, Celaeno, Elektra, Maia, Merope and Taygete. The Pleiades, who can be classified as nymphs, raised Dionysus and Zeus together. According to mythology they were pursued by the sky hunter Orion. Zeus moved the Pleiades to the sky as a constellation, but even there they are still pursued by Orion, whose constellation is located about 30° southeast of the Pleiades.

In the NGC catalogue the Pleiades are not listed separately, but there are several reflection nebulae with their own NGC numbers in the Pleiades area. These include the Maja Nebula (NGC 1432) and the Merope Nebula (NGC 1435). Only about half a minute of arc from Merope is a concentration of interstellar dust known as IC 349 or Barnard's Merope Nebula.
The Pleiades appear with an extension of about 2° about four times as large as the moon seen with the naked eye. The star cluster is about 445 light years away from the solar system and contains at least 1200 stars which are on average about 125 million years old. Thus it is one of the youngest open star clusters in our Milky Way and due to its proximity to the solar system also one of the best explored.

« Click here or the thumbnail to load a large annoted image and a size comparison to the full moon.

A more detailed image of us, taken with a longer focal length, is shown here.

The blue reflection nebulae surrounding the bright Pleiades stars are not the remains - as long suspected in the past - of gas and dust from which the stars were formed. The star cluster is
currently passing through a molecular cloud known as the Taurus-Auriga dark nebula complex. The original remnants of dust and gas that would have remained after the Pleiades stars formed would have completely dissolved in due to the enormous radiation pressure of the stars a long time ago.
The Pleiades are at present in collision with a cloud of interstellar gas and dust. Such interstellar clouds of matter always appear as brownish coloured nebulae away from bright stars, illuminated by the stars of the immediate vicinity. In this case, the bright Pleiades stars ensure that their blue light is scattered by the dust of their immediate surroundings, thus turning the Pleiades nebulae into prominent reflection nebulae.

In many prehistoric cultures the Pleiades were considered a special asterism. For example, a group of six drawn points in the caves of Lascaux is interpreted as a representation of the Pleiades.

A very important object from Central Europe, probably used for astronomy, is the so-called Nebra Sky Disk. A group of seven closely spaced points are identified as the Pleiades. Here you will find a comprehensive article in german language (information in english language) on the astronomical interpretation of the Nebra Sky Disk. It is dated to an age between 3700 and 4100 years.

« The Nebra Sky Disc. Credit:

top of page

Sun Moon Solar System DeepSky Widefield Miscellaneous Spec. Projects