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

Function Documentation

Vec6 lupnt::GcrfToIcrf(Real t_tdb, const Vec6 &rv_gcrf)

Converts a state vector from GCRF (Earth-centered) to ICRF (solar-system-barycenter-centered), by adding the Earth’s barycentric position/velocity at t_tdb.

Used by ConvertFrame to bridge between the Earth-centered GCRF hub frame and the barycentric ICRF frame, e.g. when an agent’s state must be expressed relative to the solar-system barycenter for high-fidelity N-body dynamics or SPICE-based ephemeris comparisons.

Note

Astrodynamics Convention & Modeling Reference, Version 1.1, Page 39

Parameters:

  • t_tdb – Epoch [s, TDB since J2000]

  • rv_gcrf – Position+velocity in GCRF (Earth-centered) [m, m/s]

Returns:

Position+velocity in ICRF (solar-system-barycenter-centered) [m, m/s]