sc_to_j2000

gdt.missions.fermi.gbm.localization.dol.legacy_functions.sc_to_j2000(scx, scy, scz, pos)[source]

Convert Cartesian source position from space craft frame to right ascension and declination in Earth-centered frame.

NOTE: Based on sc direction cosines derived from quaternion, and a given X,Y,Z in space craft frame

Parameters:

  • scx (np.ndarray(3, float64)) – Space craft X direction cosines

  • scy (np.ndarray(3, float64)) – Space craft Y direction cosines

  • scz (np.ndarray(3, float64)) – Space craft Z direction cosines

  • pos (np.ndarray(3, float32)) – (az, zen) position in cartesian (x,y,z)

Returns:

  • ra (float32) – Right ascension in radians

  • dec (float32) – Declination in radians