Enumeration of reference frames of inertial, fixed, local vertical local horizontal (Gauss), normal tangential crosstrack (Frenet), ICRF, J2000

Member	Value	Description
eUtFrameInertial	0	Inertial frame of the central body.
eUtFrameFixed	1	Fixed frame of the central body.
eUtFrameLVLH	2	Local vertical, local horizontal frame [Gauss frame] (x along radial, y along intrack, z along crosstrack (position cross inertial velocity))
eUtFrameNTC	3	Normal Tangential CrossTrack frame [Frenet frame] (y along tangential (inertial velocity), z along crosstrack (position cross inertial velocity), x is normal completing the triad (radius-like))
eUtFrameICRF	4	ICRF frame of the central body (origin at central body with axes parallel to ICRF).
eUtFrameJ2000	5	J2000 frame of the central body (origin at central body with axes parallel to J2000).