The planetary navigation system consists of a collection of programs that are used to perform or support navigation operations. The inputs to this system are tracking data, science instrument data, spacecraft telemetry data, and an a prior description of the solar system in terms of constant parameters. Tracking data include Doppler, range, and very long baseline interferometric signals from spacecraft and quasars. The tracking data also include troposphere, ionosphere, and solar plasma data. Science instrument data include optical images and laser range finding. Spacecraft telemetry data include attitude control and propulsion system telemetry. Solar system a prior constant parameters include initial states of the spacecraft, planets, planet attitude and rotation, gravity harmonics, inertia tensors, shape models, location of landmarks, Earth plate tectonics, and solid earth tides. The outputs from the navigation software system include spacecraft and planetary ephemerides, planet attitude as a function of time, gravity harmonics, shape models, landmark locations, inertia tensors, mass, solar pressure parameters, and propulsion maneuver parameters.