3 articles for "Proper Motion"

The true motion of the fixed stars. This motion, although very small, is noticable over long periods of time (fifty years or so) and, thus, star maps and catalogs must occasionally be updated.

See also: ♦ Stars

This is another term for "Angular Velocity". Theangular distance a body moves in a certain time period, like a year.

See also: ♦ Angular Velocity ♦ Stars

(1) Said of the motion of planet in space, as compared to any apparent motion which results from any movement of the Earth: either axial rotation, annual revolution, or the motion through space of our entire solar system.

(2) Loosely applied to the direct motion of a planet through the signs, in distinction to the diurnal rising and setting caused by the Earth's rotation.

See also: ♦ Planetary Motion