Open star cluster
Constellation bull
Position
equinox : J2000.0
Right ascension 3 h 47.4 m
declination + 24 ° 07 ′
Appearance

classification II, 3, r (Trumpler),
c (Shapley)
Brightness  (visual) 1.6 mag
Angular expansion 110.0 '
Number of stars 500
Brightest star Alkiones , 2.87 mag
Physical data

Redshift 18  ·  10 −6
Radial velocity 5.41 km / s
distance  444 ly
(136 pc )
Age 100 million years
history
Discovery time prehistoric
Catalog names
M  45 • C 0344 + 239 • OCl 421 •  Mel  22 •  Cr  42 • H 0346 + 24

The Pleiades (also Atlantiden, Atlantiaden, Siebengestirn, Taube , Seven Sisters, Gluckhenne ) are an open star cluster that can be seen with the naked eye. In the Messier catalog it has the designation M45 . They are part of our galaxy , the Milky Way . They got their name from the Pleiades of Greek mythology. The brightest stars are also named after individual Pleiades or their parents.

The star cluster is about 140 parsecs away in the constellation Taurus , comprises at least 1200 stars and is about 125 million years old.

## observation

Star map of the Pleiades with all stars up to 9 mag (yellow = the seven main stars up to 5 mag)

Since the Pleiades were known as a star group long before the invention of the telescope, only the brightest main stars are traditionally referred to as the Pleiades. In some cultures and historical representations only six stars are counted in the Pleiades. The reason for this is Pleione , which is a variable star .

Its apparent brightness fluctuates slowly but irregularly between that of Taygeta and Celaeno , so that Pleione is sometimes only seen when Celaeno can already be recognized. With the naked eye, six to nine stars can be seen, depending on the visibility conditions. The arc of vision should be set at 14.5 ° to 15.5 ° when the sky is clear; in cloudy weather with 19.5 ° to 20.5 °. In good visibility conditions, the heliacal ascent can be observed from a horizon height of 6 ° to 7 °; the sun is at this point about 9 ° below the horizon.

Surname F. apparent
brightness
Spectral
class
Mass
( ) ${\ displaystyle {M _ {\ odot}}}$
Proper movement ( mas / a ) Distance
(Lj)
Right asc. Deklin.
Alkiones 25th 02.87 B5 IIIe 6.0 019.3 −43.7 0410
Atlas 27 03.63 B8 III + B8 V 4.7 + 3.4 017.7 −44.2 0390
Electra 17th 03.70 B6 IIIe 4.65 020.8 −46.1 0405
Maia 20th 03.87 B8 III 4.2 021.0 −46.0 0360
Merope 23 04.18 B6 IVe 4.25 021.1 −43.7 0380
Taygeta 19th 04.30 B6 IV 4.4 021.2 −40.6 0410
Pleione 28 04.83 ... 5.38 B8 Vne 3.6 018.1 −47.2 0420
Celaeno 16 05.46 B7 IV 4th 019.7 −45.7 0435
Asterope 21st 05.76 B8 V 020.0 −45.9 0430
22 Tauri (Sterope II) 22nd 06.42 A0 Vn 019.6 −45.1 0445
18 Tauri 18th 05.65 B8 V 020.7 −46.5 0445
(size comparison)

The Pleiades are visible in the northern star sky from around the beginning of July to the end of April.

The Pleiades are not listed in the NGC catalog , 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. Just about half an arc minute or 0.06 light years from Merope is a concentration of interstellar dust known as IC 349 or Barnard's Merope Nebula and is kinematic is independent of the Pleiades.

The open star cluster appears with an extension of approx. 2 °, about four times as large as the moon, which was copied into the bottom left for comparison. The physiological perception of overestimating the size of bright objects in the sky is not taken into account.

## Cultural meaning

Nebra Sky Disc The Pleiades between full moon and waxing moon
The Pleiades in the constellation Taurus
The red circle indicates their position.

The Pleiades were considered special stars in many cultures. So z. B. interpreted a group of six drawn points in the caves of Lascaux as a representation of the Pleiades.

An important object from Central Europe, probably used for astronomy, is the Nebra Sky Disc . A group of seven closely spaced points is identified with the Pleiades.

The seven stars were first mentioned in Sumer as a constellation ( mul.mul ) and referred to as the seven deity of the great gods .

In the Bible the Pleiades are mentioned in the books of Job ( Hi 9.9  EU ; 38.31 EU ) and Amos ( Am 5.8  EU ): "Do you tie the ribbons of the seven stars or do you loosen the fetters of Orion?" ( Hi 38.31  ELB ).

In the biblical myth, the Pleiades are symbolized as doves, which herald the awakening of nature as a spring star.

They were considered the stars of Enki or stars that stand where the east wind comes from . In the astrolabe B , which dates from the 12th century BC The Pleiades represent the second sign of the zodiac, Taurus .

As a pictorial glyptic symbol and representation as the seven deity , the beginnings can be found among the Assyrians in the period from the 15th to the 14th century BC. u. Z. , the Mitanni period. The Pleiades often adorned Assyrian monuments and were invoked in prophetic texts . In Babylonia , the seven stars played a more subordinate role and was therefore hardly depicted in pictures. The Babylonians saw in it the magic number forty , because the Pleiades were hidden by the sun for 40 days.

The brightest stars are named after characters from Greek mythology , the Titan Atlas (hence the other name), his wife Pleione and their seven daughters Alkyone , Asterope , Celaeno , Elektra , Maia , Merope and Taygete . The Pleiades , who can be classified as nymphs , educated Dionysus and Zeus . According to mythology, Orion persecuted them. Zeus placed them in the sky as a constellation, but there too they are still being pursued by Orion, whose constellation is located about 30 ° southeast of the Pleiades.

In Japan , the six brightest stars in the Pleiades are seen as the Subaru constellation , from which the name and trademark of the Japanese automobile brand Subaru is derived.

In Arabic literature, the Pleiadesالثريا called ath-thurayya . The name also became a female first name in Turkish (as Surayya ) and in the Arabic-speaking world (e.g. Soraya Obaid ). It is also the name of the Thuraya satellite phone system that is based in the United Arab Emirates .

A Celtic iron sword from the third century BC, found in Allach near Munich in 1891, is executed with gold inlays showing the Pleiades.

### Agricultural and hunter's calendar star

For the Bedouins , the rise of the Pleiades signals summer and its fall signals winter: “The Pleiades rise over a dry grain sheaf and sink when the valley becomes a brook.” This corresponds to the Jewish view: “The world can because of the coldness of the Pleiades only exist because the Sirius compensates with its heat. "

The Greeks and Romans (Latin Vergiliae ) regarded the early set of the seven stars at the beginning of November as the sign of cultivation and the end of shipping. With the early rise around May 20th at that time, the Pleiades were regarded as a signal generator for the beginning harvest (see also Gezer calendar ).

Flavius ​​Josephus mentions that when the seven stars went down around the time of the Feast of Tabernacles in November, the onset of rain put an end to the lack of water. The Maasai in Africa use the Pleiades as a rainy season signal star . The Arabic astrology published by Gladys Dickson names May 20th for early dawn and November 17th for early sunset (see also: Heliakisch ); In the ancient Greek tradition, the Geoponica (chap. 1) mentions the corresponding dates for June 10th and November 4th.

The Pleiades constellation was of vital importance to the Blackfoot Indians of North America. The Blackfoot were nomadic hunters and gatherers. They lived in small groups in bison skin tipis . Sometimes a few groups or even an entire sub-tribe came together to form hunting expeditions. The state of the Pleiades at the beginning of the dry season was the starting signal for an elaborate hunt for the huge bison herds. When the Pleiades have disappeared from the starry sky at the end of April, the bison have also disappeared.

In several Neolithic circular moats in Lower Austria, one of the 4–6 entrance gates is in the direction of the early rise of the Pleiades. Heliacal rise is the time or direction in which a star first becomes visible at dawn, after having been invisible for a few months - outshone by the sun. A few millennia before the new era, this early rise of the Pleiades was at the astronomical beginning of spring at the end of March and probably served as a clue to start sowing .

The fact that this cloud of stars and not a more easily observable bright star was used indicates the special importance of the Pleiades for some cultures, as the Nebra Sky Disc suggests.

### Pacific New Year celebrations

In Pacific cultures, the rise of the Pleiades determines the New Year celebrations . In New Zealand , Matariki is one of the most important Māori festivals . On the islands of French Polynesia , the Pleiades Festival is celebrated once a year. It's a kind of New Year festival, a festival of abundance and change.

## Covered by the moon

Pleiades cover by the moon, sketch (7 August 2007)
Pleiades cover by the moon, photo (23/24 February 2007)

Every 18.6 years, the Pleiades are regularly covered by the moon for a longer period of time . The last series ran from 2005 to 2009 (here the events that can be observed in Central Europe):

• August 7, 2007 (01:30 a.m. CEST)
• October 28, 2007 (1:00 a.m. CEST)
• December 21, 2007 (10:45 p.m. CET)
• March 12, 2008 (7:15 p.m. CET)
• August 23, 2008 (from midnight with moonrise)
• September 20, 2008 (5:00 a.m. CEST)
• November 13, 2008 (7:15 pm CET)
• January 7, 2009 (6:30 p.m. CET)
• July 18, 2009 (3:15 a.m. CEST)
• October 7, 2009 (11:45 p.m. CEST, close by)
• December 29, 2009 (3:15 a.m. CET)

After that, the Pleiades will only be temporarily covered by the moon for an observer on Earth from 2024. The Pleiades, together with the Hyades, form the so-called Golden Gate of the Ecliptic .

## literature

Commons : Pleiades  - Collection of images, videos and audio files
Wiktionary: Pleiades  - explanations of meanings, word origins, synonyms, translations