Shared geometry and inputs
Every event on this site is one body hiding another from a third, and every computation of one needs the same inputs. This group holds them:
- Foundations: the fundamental plane and the Besselian elements. The same construction serves solar eclipses, transits and occultations, with a shadow cone for the Sun and a cylinder for a star.
- Earth model and time scales: the ellipsoid, terrain, ΔT, refraction, light-time and reference frames.
- Lunar and solar model: the JPL ephemerides, the lunar radius ratio , the centre of figure and libration.
- Software and repositories: the production programs, open libraries, repositories and datasets.
The groups that follow apply these inputs to one kind of event each. Their pages link back here rather than repeating them.