In celestial mechanics true longitude is the ecliptic longitude at which an orbiting body could actually be found if its inclination were zero. Together with the inclination and the ascending node, the true longitude can tell us the precise direction from the central object at which the body would be located at a particular time.
- l = ν + ϖ
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- Roy, A. E. (1978). Orbital Motion. New York, NY: John Wiley & Sons. p. 174. ISBN 0-470-99251-4.
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