• Michael Soffel
  • Ralf Langhans
Part of the Astronomy and Astrophysics Library book series (AAL)


If a stellar position is measured from the Earth, it will vary because of refraction in the Earth’s atmosphere, parallax, aberration, proper motion and precession, nutation, and polar motion. Parallax and aberration require the selection of a reference point that usually is chosen as the barycenter of the solar system. For that reason, the computation of parallax and aberration requires solar system ephemerides.


Proper Motion Zenith Distance Celestial Pole Reference Epoch Refraction Correction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Michael Soffel
    • 1
  • Ralf Langhans
    • 1
  1. 1.Institute for Planetary GeodesyDresden Technical University Lohrmann ObservatoryDresdenGermany

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