In observational astronomy, changing stars is understood to mean those stars whose position changes noticeably in short periods of time. These include the planets (the so-called walking stars ), the moon , the sun as well as asteroids and comets . These “walking” celestial bodies are in contrast to the fixed stars , which always take the same position in relation to one another in the starry sky .
The concept of the changing stars and their relation to the fixed stars was a central aspect of pre-ancient and ancient proto- astronomy and cosmology , as only the seven celestial bodies, sun , moon , Mercury , Venus , Mars , Jupiter and Saturn, regularly visible to the naked eye were visible until modern times. It also plays an important role in Kepler's astrological work, as well as in his scientific work, such as the Harmonice mundi . The calculation of the “ star locations ” is much more difficult for changing stars than for fixed stars (see also ephemeris ).
In parlance, changing stars and changing stars are often used synonymously. The word Wandelstern is a 17th century neologism . It originated as a transmission from planet (from Greek πλανάομαι planáomai , wandering around, wandering around ') and was initially considered a "poetic language". The extension to comets (tail stars) can be found, for example, in Goethe . Krünitz suggested the designation Irrstern for comets .
The term fixed star is common in astronomy (although also out of date since the stars' proper motion was known). The expression " changeable star" is in no way sufficient for the precise technical language of astronomy. Nevertheless, the term has its place in the introductory didactics of astronomy to this day, because it clearly illustrates numerous special problems in theoretical celestial mechanics , astronomical phenomenology , astronomical time measurement as well as numerical modeling or the construction of planetariums .
- M. Jeitler: Transformation of heliocentric to geocentric changing star coordinates. Tightening of the "Ahnert tables" . Presentation, in: Use of Astronomical Yearbooks. 2nd Sternfreunde Seminar, 1974. Zeiss Planetarium of the City of Vienna and Austrian Astronomical Association 1974
- Wolfgang Vollmann: Changing stars; Physical changing star data ; Hermann Mucke: Changing star parallaxes; Estimation of the visibility of the bright moving stars and stars - earth-wide, hourly, from −2000 to +4000 ; Norbert Pachner: The main positions of the changing stars. All articles in: Hermann Mucke (Hrsg.): Modern astronomical phenomenology . 20th Sternfreunde Seminar , 1992/93. Zeiss Planetarium of the City of Vienna and Austrian Astronomical Association 1992, various p. ( Weblink ).
- For example Michael Tirabassi: Plato ( Memento of the original from June 24, 2012 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. Greek Science course, Prof. Gregory Crane, Tufts University, 1995 (engl.)
- See Introduction to Astronomy - Kepler's Discovery (Engl.); Christian Pinter: A reflection of the universe - in the midst of the turmoil of the Thirty Years' War, Hans Ulrich von Eggenberg, imperial governor of Inner Austria, set up an idyll in Graz: a foray through a refuge of complex allegory and number mysticism. In: Wiener Zeitung , Saturday / Sunday, 11./12. May 2013
wandelstern, m. . In: Jacob Grimm , Wilhelm Grimm : German Dictionary . Hirzel, Leipzig 1854–1961 ( woerterbuchnetz.de , University of Trier).
Wandelstêrn . In: Adelung, Vol. 4, Col. 1379.
- wandelgestirn, n., Comet . In: Grimm: German dictionary. Hirzel, Leipzig 1854–1961 ( woerterbuchnetz.de , University of Trier).
- Wandelstern . In: JG Krünitz: Economic Encyclopedia . 1858, 233, p. 302; see. wandering star, 3) comet . In: Grimm: German dictionary. Hirzel, Leipzig 1854–1961 ( woerterbuchnetz.de , University of Trier).
- Cf. Carl Zeiss AG: SKYMASTER® ZKP 4 LED - The Small Planetarium for the Digital Age ( Memento of the original from December 15, 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. (PDF; 912 kB), p. 3
- See the term " Wandelgestirne" on the homepage of the Stuttgart Planetarium
- David Colarusso: Wandering Stars. How to Calculate the Positions of the Planets (as an example in English)