What direction does a prograde motion refer to in planetary motion?

Prograde motion in planetary motion refers to the direction in which most planets, including Earth, orbit around the Sun, which is from west to east when viewed from above the Sun's north pole. This eastward movement is the standard direction of rotation and revolution for the majority of the bodies in our solar system, and it aligns with the counterclockwise movement of the planets when observed from this perspective.

Understanding this concept is crucial, as it distinguishes the regular orbital path of planets from retrograde motion, which occurs when a planet appears to move in the opposite direction (east to west) relative to the stars. The notion of prograde motion serves as a foundational element in celestial mechanics and astronomy, illustrating the overall dynamics of how celestial bodies move in our solar system.