astroforge.force_models.F_mp#

astroforge.force_models.F_mp(t, y)[source]#

A built-in medium-fidelity force model for propagating a satellite. This model includes:

  • Two body + J2 perturbation Earth gravity

  • Third body gravitational perturbation from the Sun

  • Third body gravitational perturbation from the Moon

Parameters:
  • t (float) – Time at which the force model is to be evaluated, expressed as a Modified Julian Date (MJD) in the UT1 time system.

  • y (NDArray[np.float64]) – State vector; should have shape (6, ) with the first three parameters corresponding the 3D position, and the last three parameters corresponding to the 3D velocity of the satellite. Units are km and km/s.

Returns:

ydot – Derivate of the state vector.

Return type:

NDArray[np.float64]