Reference Frames Module¶

Reference frame transformations between inertial (ECI) and Earth-fixed (ECEF) coordinate systems.

Transformation Categories¶

Brahe provides three categories of reference frame transformations:

ECI ↔ ECEF¶

Generic transformations using common "Earth-Centered Inertial" and "Earth-Centered Earth-Fixed" naming convention. Currently maps to GCRF ↔ ITRF transformations.

GCRF ↔ ITRF¶

Explicit transformations between Geocentric Celestial Reference Frame (inertial) and International Terrestrial Reference Frame (Earth-fixed). Uses IAU 2006/2000A CIO-based theory with classical angles.

EME2000 ↔ GCRF¶

Constant frame bias transformations between Earth Mean Equator and Equinox of J2000.0 (classical inertial) and GCRF (modern inertial).