trigonometric parallax

Definition

Astronomy

  • The parallax of a star determined by measurement of its position in the sky – using trigonometrical methods – rather than by spectroscopic techniques. Such parallaxes are ‘true’ parallaxes, whereas spectroscopic ones are at one remove from the parallax method and derive from results it has produced.
http://www.dictionarycentral.com/definition/trigonometric-parallax.html