Star map

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A star map (also called a sky map ) shows the position of the stars and constellations in the sky on a map . The star brightnesses are often also represented by signatures.

A related set of star maps that depict the entire starry sky is called a star atlas . Older atlases are partly limited to the northern sky .

Star map by JE Bode from 1782, from the "Presentation of the stars on XXXIV panels"
The constellation Orion from Bayer's Uranometria star atlas

Early depictions of the starry sky

Ancient Egyptian images in the grave ( TT353 ) of Senenmut are recognized as the oldest representation of entire constellations . On earlier representations of the stars, e.g. B. the sky disk of Nebra , the stars (with the exception of one group that probably represents the Pleiades ) were probably distributed by the artist rather randomly. Apart from wall paintings, celestial globes and planispheres are known from antiquity, some of which were used for decoration, but also for astronomical work.

The development of the maps goes hand in hand with the creation of star catalogs . Ptolemy describes the construction of celestial globes as well as planispheres (rotatable star maps). Planispheres have not been preserved, but Carolingian copies of the description of the constellation of Aratos contain planispheres and representations of individual constellations, which were probably copied from ancient models. However, these maps only show the constellations, not the individual stars. From the 9th century, there are more and more depictions of the constellations, especially as part of copies of the Poeticon Astronomicon by Hyginus , which became the standard source of the Middle Ages on the myths of the constellations. These representations, however, place stars, if they are also depicted at all, in fantasy positions that match the respective image.

Historical star maps

Woodcut by Albrecht Dürer 1515. The illustration of the northern sky shows the twelve signs of the zodiac in twelve sections of a circle and the four famous astronomers Aratus Cilix , Ptolemeus Aegpteus , M. Manilius Romanus and Azophi Arabus in the corners .
Star map by Frederik de Wit

For a long time only maps of the individual constellations were published, the positions of which were mostly based on the outdated Greek data of Ptolemy and Hipparchus (the catalog of which was lost in the West in the course of the early Middle Ages ), if they were not drawn by hand. Ptolemy's catalog was preserved in the Arab world and Byzantium , but it was only with the measurements of astronomers like Tycho Brahe that modern positions became available, which very quickly became the standard.

In 1515 the first printed planispheres by Albrecht Dürer , Johannes Stabius and Konrad Heinfogel appeared , showing the entire sky on two maps: the hemispheres north and south of the ecliptic .

In 1535 a Hyginus edition with stars at the approximate positions and lines of a graticule was published in Cologne and in 1570 star maps appear with Alessandro Piccolomini's De le stelle fisse , which only show the stars in approximately correct positions and do not use the figurative representation of the constellations.

Johann Bayer finally published the Uranometria 1603, the first atlas of the entire sky instead of a map collection of selected constellations or less precise planispheres. The positions in the Uranometria are based on Tycho Brahe's observations, who was famous for his observational accuracy. The size of the individual maps is still tailored to the constellations shown, so that there is no uniform scale. Andreas Cellarius ' Harmonia Macrocosmica from 1661 is considered an artistic masterpiece of the sky atlases, although it lags behind more detailed works such as Uranometria in terms of scientific cartography , but vividly summarizes the astronomical knowledge of the time on incomparable copper engravings.

The actual representation of the sky, however, continued to develop both scientifically and artistically until the Uranographia by JE Bode appeared in 1801 . The atlas consisted of 20 maps in the format 103 cm × 70 cm, making it the atlas in the largest format to this day. The copperplate engravings are very filigree and rich in detail and show around 17,000 objects in the fixed star sky .

Due to this abundance, people increasingly abandoned the figurative depiction of the constellations and limited themselves to the drawn connecting lines of the main stars. Even the latter appear today only in popular science maps.

Today's star maps

Map of the night sky: star positions from the Bright Stars Catalog, 5th Edition

Drawn maps, i.e. representations from a catalog, are only used professionally for limited purposes today, but remain an important popular and amateur astronomical tool. Otherwise, either only the catalogs are published, from which you can print excerpts as required, or photographic maps that are created directly from telescope images, such as the Digitized Sky Survey .

Today, however, many people tend to use astronomical planetarium software, which often contains extensive star catalogs .

When observing the stars outdoors, rotatable star maps ( planispheres ) are used.

If a star map is to be suitable for angle measurements, stereographic projection is usually chosen. On it all curves intersect at the same angle as on the celestial sphere ( angular accuracy , and moreover, general circularity applies ).

See also

literature

Modern star atlases

  • Falkauer Atlas (Equinox 1950.0) - Hans Vehrenberg (photographic), ca.1965
  • Atlas Stellarum (1950.0) - Hans Vehrenberg (photographic), Treugesell-Verlag 1970
  • True Visual Magnitude Photographic Star Atlas (1950.0) - Christos Papadopoulos and Charles Scovil (photographic)
  • Atlas Borealis, Atlas Eclipticalis, Atlas Australis (1950.0) - Antonín Bečvář
  • Atlas Coeli Skalnate Pleso (1950.0) - Antonín Bečvář
  • Atlas Coeli Novus 2000.0 (2000.0) - Successor to the Atlas Coeli
  • Sky Atlas 2000.0 - Wil Tirion
  • Cambridge Star Atlas (abridged version of Sky Atlas 2000.0)
  • Photographic star atlas - the entire sky on 82 map sheets - Axel Mellinger / Ronald Stoyan , Oculum-Verlag, Erlangen 2010, ISBN 978-3-938469-42-2
  • Millennium Star Atlas (3 volumes)
  • Deep Sky Travel Atlas (with "Telrad" target circles)
  • Atlas for Sky Watchers - Erich Karkoschka
  • The Great Atlas of the Sky - Piotr Brych (12 mag)
  • TriAtlas - José Ramón Torres and Casey Skelton (12.6 mag)

Rotatable star maps (planispheres)

  • Rotatable cosmos star map - Hermann-Michael Hahn, Gerhard Weiland - Contains the brightest deep sky objects
  • Rotatable sky map (oculum) - Know where the stars are at every hour - Michael Feiler, Stephan Schurig - Contains 700 stars and almost 250 celestial objects
  • Postscript star map which is under GPL. http://www.infodrom.north.de/~muh/Astronomie/Drehbare/

Web links

Commons : Star Maps  - collection of images, videos and audio files

General

Individual maps digitized (historical)

Individual map series digitized (modern)

Interactive star maps

Individual evidence

  1. ↑ https://www.duden.de/rechtschreibung/Himmelskarte
  2. ^ Astronomy in Nuremberg. The star maps by Albrecht Dürer , accessed on December 9, 2013
  3. ↑ Dirk Lorenzen : Albrecht Dürer and the star map. In: Stardate. Deutschlandfunk , December 9, 2013, accessed December 9, 2013 .
  4. ↑ lindahall.org (English) ( Memento of the original from December 14, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , accessed December 9, 2013 @1@ 2Template: Webachiv / IABot / www.lindahall.org
  5. ↑ In contrast to today's star maps, which have the celestial poles as their center:
    - The ecliptic poles are stable, while the celestial poles move ( cycle of precession ). Here ( memento of the original from April 18, 2012 in the Internet Archive )     Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. (Bayer’s Uranometria from the Linda Hall Library of Science, Engineering, & Technology, accessed December 9, 2013) one can see the difference of 400 years. The North Star (the large star to the left of the lower center) is closer to the celestial north pole today. Unfortunately, someone has drawn the little car incorrectly in this issue . - The zodiac ( zodiac ) was certainly more important at that time (keyword: astrology ). see also: Astronomy in Nuremberg. Celestial Pole and Ecliptic Pole . Retrieved December 10, 2013 @1@ 2Template: Webachiv / IABot / www.lindahall.org

  6. ^ The Millennium Star Atlas