Direct motion, a motion from west to east among stars.
Disk, the visible surface of sun, moon, or planets.
Distance of stars, [70].
Double stars, [210].
Earth, revolution of, [109]; in space, [142]; irregular figure, [145].
Eccentricity of an ellipse, the distance of either focus from centre divided by half the major axis.
Eclipse (a disappearance), [157].
Ecliptic, the apparent annual path of the sun among the stars; plane of, [106].
Egress, the passing of one body off the disk of another.
Elements, the quantities which determine the motion of a planet: data for predicting astronomical phenomena; table of solar, [274].