Function lupnt::MoonCiToOp(Real, const Vec6&)

Function Documentation

Vec6 lupnt::MoonCiToOp(Real t_tdb, const Vec6 &rv_ci)

Converts a state vector from MoonCi (Moon-centered inertial) to MoonOp (Moon orbit-plane frame: z-axis along the Earth-Moon orbit-normal, x-axis toward the lunar north pole projected into the orbit plane) at epoch t_tdb.

Used by ConvertFrame to express lunar-orbiter states in the frozen-orbit “orbit plane” frame of Ely (2005), e.g. for designing/analyzing stable frozen elliptical inclined lunar orbits. Internally applies the transpose of RotMoonOpToCi.

Note

T. A. Ely, ‘Stable Constellations of Frozen Elliptical Inclined Lunar Orbits’, J of Astronaut Sci, vol. 53, no. 3, pp. 301–316, Sep. 2005, doi: 10.1007/BF03546355.

Parameters:

  • t_tdb –

  • rv_ci –

  • t_tdb – Epoch [s, TDB since J2000]

  • rv_ci – Position+velocity in MoonCi (Moon-centered inertial) [m, m/s]

Returns:

Vec6

Returns:

Position+velocity in MoonOp (Moon orbit-plane frame) [m, m/s]