In astrodynamics relative angular momentum () of orbiting body () relative to central body () is the moment (physics) of ()'s relative linear momentum:

where:

• is orbital position vector of the orbiting body relative to the central body,
• is orbital velocity vector of the orbiting body relative to the central body,
• is mass of the orbiting body.

For body orbiting a central body is always perpendicular to the osculating orbital plane determined by orbital position and velocity vectors.

Uses

In astrodynamics relative angular momentum is usually used to derive specific relative angular momentum ():

where:

• is mass of the orbiting body.

See also

• Specific relative angular momentum
• Linear momentum
• Momentum (physics)