| When the line of apsides points towards the Sun, the eccentricity reaches a maximum. |
| The angle through which the radius vector rotates in going between two consecutive apsides is called the apsidal angle. |
| Here, is the Sun, the planet, the geometric center of the orbit, the equant, and the line of apsides. |
| The line of apsides is a line which passes through both periapsis, Cassini's closest approach to Saturn in an orbit, and apoapsis, the farthest spot in the orbit from Saturn. |
| For the moon, the line of apsides completes one revolution around the sky in a period of 8.85 years. |
| At time II the line of apsides has turned through 90 degrees and we get a symmetric eclipse, indistinguishable from a circular orbit. |
