In celestial mechanics, the relative angular momentum (
where:
For a body in an unperturbed orbit about a central body, the orbital plane is stationary, and the relative angular momentum (
For perturbed orbits where the orbital plane is in motion, the relative angular momentum vector is perpendicular to the (osculating) orbital plane at only two points in the orbit.
Uses
In astrodynamics relative angular momentum is usually used to derive specific relative angular momentum (
where: