Frame Transforms¶
The satkit.frametransform module includes functions to rotate between multiple inertial and Earth-fixed coordinate frames.
Frame transforms are generally output as Quaternions. See related documentation here.
Coordinate Frames¶
The satkit.frametransform module supports transforms between the following frames:
GCRF— Geocentric Celestial Reference FrameITRF— International Terrestrial Reference FrameTEME— True Equator, Mean Equinox FrameMOD— Mean of Date FrameTIRS— Terrestrial Intermediate Reference SystemCIRS— Celestial Intermediate Reference System
Calculation Notes¶
Transformation between the GCRF and the ITRF is performed via the detailed calculations described by the International Earth Rotation and Reference System Service in their Technical Note 36: https://www.iers.org/IERS/EN/Publications/TechnicalNotes/tn36.html. This is a computationally expensive calculation.