Astro*Dictionary by Michael Erlewine
2 articles for "Astrometric"
Astrometric Ephemeris [Astro*Index]An ephemeris giving the astrometric position of a body.
See also:Astrometric Position [Astro*Index]
♦ Ephemeris
An astrometric position of a body is obtained by adding the planetary aberration to its value from the geometric ephemeris, and subtracting stellar aberration (from which the E-terms have been omitted). Observations corrected only for geocentric parallax and referred to catalogue mean places of comparison stars may be directly compared with positions given by an astrometric ephemeris.
See also:
♦ Planetary Aberration ♦ Geometric Ephemeris ♦ Stellar Aberration ♦ Geocentric Parallax
Astro*Index Copyright © 1997 Michael Erlewine