Pleiades

The Pleiades (also Atlanteans, Atlantiaden, Pleiades, Seven Sisters, mother hen ) is an open cluster of stars can be seen with the naked eye. In the Messier catalog he has the designation M45. They are part of our galaxy, the Milky Way.

Observation

Since the Pleiades were known as the Stern Group long before the invention of the telescope, only the brightest main stars are traditionally often called Pleiades. In some cultures, and historical accounts only six stars are counted among the Pleiades. The reason for this is Pleione, which is a variable star.

Its apparent brightness varies slowly but irregularly between that of Taygeta and Celaeno so that Pleione is sometimes only seen when Celaeno can be already detected. With the naked eye, therefore, according to visibility conditions, to identify six to nine stars. The arc of vision is to start with a clear sky at 14.5 ° to 15.5 °; in cloudy weather with 19.5 ° to 20.5 °. The heliacal rising is observable in good visibility conditions from a horizon of 6 ° to 7 °; the sun is at this time about 9 ° below the horizon.

The Pleiades are visible approximately from early July to the end of April in the northern night sky.

The cluster is about 380 light years from Earth in the constellation Taurus, including at least 1,200 stars and is about 125 million years old.

In NGC catalog of the Pleiades are not listed, but there are several in the area of the Pleiades reflection nebula NGC with their own numbers. These include the Maja - nebula NGC 1432 and the Merope nebula NGC 1435th Only about half a minute of arc or 0.06 light years from Merope away is a concentration of interstellar dust, which is known as IC 349 or Barnard's Merope Nebula and kinematic is independent of the Pleiades.

The open cluster appears about four times as large as the moon, which was copied to compare the bottom left of the picture with an extension of approximately 2 °. Unconsidered is the physiological perception to overestimate bright objects in the sky in their size.

History

The Pleiades were in almost every culture as a particular star, for example, as a group of six points drawn in the caves of Lascaux; above the aurochs they are also identified with the Pleiades.

The Pleiades was first mentioned in writing as a constellation in Sumer ( mul.mul ) and as a seven- deity of the great gods ( DIMIN.BI.DINGIRmesGALmes ) refers. They were considered stars of Enki or stars that are there, where the east wind is coming. In Astrolabe B, which dates from the 12th century BC, the Pleiades represent the second zodiac sign Taurus.

As a figurative Glyptik symbol and representation as a seven- deity, the beginnings find among the Assyrians in the time of the 15th to 14th century BC, the Mitanni time. Often the Pleiades adorned Assyrian monuments and were called in prophetic texts. In Babylonia the Pleiades played a more limited role and was therefore hardly depicted. The Babylonians saw in him the magic number forty, as the Pleiades were covered for 40 days from the sun.

Supposedly, the Pleiades are represented on the Early Bronze Age Nebra Sky Disk.

The brightest stars are named after figures of Greek mythology, the Titan Atlas ( hence its other name), his wife Pleione and their seven daughters, Alcyone, Asterope, Celaeno, Electra, Maia, Merope and Taygete. The Pleiades, which are classified as nymphs reared Dionysus and Zeus. According to mythology, they were pursued by Orion. Zeus displaced as a constellation in the sky, but even there, they are still haunted by Orion, the constellation of about 30 ° to the southwest, the Pleiades.

The Japanese name of the Pleiades is Subaru. The hallmark of the automaker same therefore shows six stars in a similar arrangement.

In the Arabic literature, the Pleiades الثريا ath - Thurayya be called. The name was also a female name in Turkish (as Surayya ) and the Arabic countries (eg Soraya Obaid ). It is also the name of the satellite phone Thuraya system, which has its headquarters in the United Arab Emirates.

Agricultural and waidmännisches calendar star

For the Bedouins of the rising of the Pleiades signaled the summer and fall of the winter: " The Pleiades go on over skinny mow and when the valley of the creek is. " This corresponds to the Jewish view: "The world may be because of the cold of the Pleiades therefore only exist because of Sirius makes its heat for compensation. "

The Greeks and Romans (Latin Vergiliae ) regarded the early demise of the Pleiades in early November as the sign of the field order and the end of the cruise. With the early rise at the former May 20 Pleiades were seen as a signal generator for the onset of harvest (see also Gezer Calendar).

Flavius ​​Josephus mentions that the demise of the Pleiades, the lack of water makes an end around the time of the Feast of Tabernacles in November, the rain started. The Maasai in Africa use the Pleiades at the present time as the rainy season signal constellation.

Edited by Gladys Dickson Arab astrology called 20 May for the Fruehauf and November 17 for the spring demise (see also: Heliakisch ); in the ancient Greek tradition mentions the Geoponica (Chapter 1), the corresponding data for June and 4 November 10.

For the Blackfoot Indians of North America the constellation of the Pleiades was crucial. The Blackfoot were nomadic hunters and gatherers. They lived in small groups in tepees made ​​of bison skins. For hunting expeditions sometimes joined some groups or even an entire sub-tribe together. The state of the Pleiades at the beginning of the dry season was the start signal for an elaborate hunt the vast herds of bison. Are then the Pleiades disappeared in the night sky in late April, the bison are gone.

Occultation by the moon

All 18.6 years, the Pleiades covered over a longer period regularly from the moon. The last series went from 2005 to 2009: (here the observable events in Central Europe )

• August 7, 2007 ( 01:30 clock CEST)
• October 28, 2007 ( 01:00 clock CEST)
• December 21, 2007 ( 22:45 clock CET)
• March 12, 2008 ( 19:15 clock CET)
• August 23, 2008 ( at midnight with the moon rising )
• September 20, 2008 ( 05:00 clock CEST)
• November 13, 2008 ( 19:15 clock CET)
• January 7, 2009 ( 18:30 clock CET)
• July 18, 2009 ( 03:15 clock CEST)
• December 29, 2009 ( 03:15 clock CET)

After that, it will not be back from 2024, for an observer on Earth to temporary occlusion of the Pleiades by the Moon. Together with the Hyades, the Pleiades give the golden gate of the ecliptic.