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Ecliptic Declinations and Right Ascenesions.

According to Eqs. (13) and (14), the celestial coordinates of a point on the ecliptic circle (i.e., $\beta = 0$) which has ecliptic longitude $\lambda$ are specified by
$\displaystyle \sin\,\delta$ $\textstyle =$ $\displaystyle \sin\epsilon\,\sin\lambda,$ (15)
$\displaystyle \tan\,\alpha$ $\textstyle =$ $\displaystyle \cos\epsilon\,\tan\lambda.$ (16)

The above formulae have been used to construct Tables 2 and 3, which list the declinations and right ascensions of a set of equally spaced points on the ecliptic circle.

Richard Fitzpatrick 2010-07-21