The definition of the ecliptic

  title={The definition of the ecliptic},
  author={Hiroshi Kinoshita and Shinko Aoki},
  journal={Celestial mechanics},
The ecliptic as a mean orbital plane of the Sun in Le Verrier's theory is a mean orbital plane determined from the secular parts of the longitude of the ascending node and the inclination of the Sun with respect to a reference plane. On the other hand, the ecliptic in Newcomb's theory is so chosen that the latitude with respect to his ecliptic does not have cosg nor sing whereg is the mean anomaly of the Sun. The two definitions are really different in spite of their apparent similarity… 

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