Astrolabe Glossary and Notes


The angular distance between the first point of Aries and the line from the celestial pole through the celestial object to the ecliptic. In other words, the mediation is the degree of the ecliptic that crosses the meridian at the same time as the celestial object. This value is measured counter-clockwise from the first point of Aries and is reported in degrees of a sign. Although mediation was formerly used with declination to locate a celestial object, astronomers now commonly pair right ascension with declination.
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