| 释义 |
Besselian elements Besselian elements[bə′sel·yən ¦el·ə·mənts] (astronomy) Data on a solar eclipse, giving, for selected times, the coordinates of the axis of the moon's shadow with respect to the fundamental plane, and the radii of umbra and penumbra in that plane; the data allow one to derive local circumstances of the eclipse at any point on the earth's surface. |