In astrodynamics

Astrodynamics

Orbital mechanics or astrodynamics is the application of ballistics and celestial mechanics to the practical problems concerning the motion of rockets and other spacecraft. The motion of these objects is usually calculated from Newton's laws of motion and Newton's law of universal gravitation. It...

 orbit phasing is the adjustment of the time-position of spacecraft along its orbit

Orbit

In physics, an orbit is the gravitationally curved path of an object around a point in space, for example the orbit of a planet around the center of a star system, such as the Solar System...

, usually described as adjusting the orbiting spacecraft's true anomaly

True anomaly

In celestial mechanics, the true anomaly is an angular parameter that defines the position of a body moving along a Keplerian orbit. It is the angle between the direction of periapsis and the current position of the body, as seen from the main focus of the ellipse .The true anomaly is usually...

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This is predominantly used in satellite positioning, especially if the satellite is in geosynchronous orbit

Geosynchronous orbit

A geosynchronous orbit is an orbit around the Earth with an orbital period that matches the Earth's sidereal rotation period...

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Orbit phasing is required for a successful approach to a space station in a docking maneuver.