the angular distance of a point on the celestial sphere from the great circle that is perpendicular to the ecliptic at the point of the vernal equinox, measured through 360° eastward parallel to the ecliptic.
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the angular distance measured eastwards from the vernal equinox to the intersection of the ecliptic with the great circle passing through a celestial body and the poles of the eclipticAlso called: ecliptic longitude
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
The position of a celestial object east of the vernal equinox along the ecliptic. Celestial longitude is measured in degrees eastward from the vernal equinox (0°) to the point where a great circle drawn through the object and the poles of the ecliptic intersects the ecliptic. Compare celestial latitude. See more at ecliptic coordinate system.
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