| UTC minus TAI | The differences between UTC function and TAI. NB: UTC is NOT time, but a non-differentiable function of time. Units: secobds |
| UT1 minus TAI | Parameter UT1 describes orientation of the Earth with respect to the axis of its rotation. It is defined as a prturbational ngle with respect to a uniform rotation with nominal angular velocity 7.292115146706979 · 10-5 rad/sec. Units: seconds. |
| X pole coordinate | Parameter X pole coordinate describes the offset of the Earth's pole in the crust-fixed coordinate system along the Greenwich meridian towards axis X. Units: arcseconds. |
| Y pole coordinate | Parameter Y pole coordinate describes the offset of the Earth's pole in the crust-fixed coordinate system along the meridian 90° west, opposite to axis Y. Units: arcseconds. |
| Nutation offset Δψ | |
| Nutation offset Δε | |
| Euler angle 1 | Euler angle with respect to axis 1. Does not take into account harmonic terms. Units: rad. |
| Euler angle 2 | Euler angle with respect to axis 2. Does not take into account harmonic terms. Units: rad. |
| Euler angle 3 | Perturbation of the Euler angle with respect to axis 3 after subtraction a linear trend with angular velocity 7.292115146706979 · 10-5 rad/sec. Does not take into account harmonic terms with periods less than 4 days. Units: rad. |
| Length of day | |
| UT1 rate | |
| X pole rate | Rate of change of X pole coordinate. Units: arcsec/day. |
| Y pole rate | Rate of change of Y pole coordinate. Units: arcsec/day. |
| Rotation matrix | 3 × 3 rotation matrix that tranforms a vector in the crust-rfixed coordinate system in to the inertial coordinate system for accounting the Earth rotation. The order of nine terms: (1,1), (2,1), (3,1), (1,2), (2,2), (3,2), (1,3), (2,3), (3,3) Units: dimensionless. |
| Rotation matrix rate | Time derivative of the 3 × 3 rotation matrix that transforms a vector in the crust-rfixed coordinate system in to the inertial coordinate system for accounting the Earth rotation. The order of nine terms: (1,1), (2,1), (3,1), (1,2), (2,2), (3,2), (1,3), (2,3), (3,3) Units: 1/s. |
| Rotation matrix acceleration | Second time derivative of the 3 × 3 rotation matrix that transforms a vector in the crust-rfixed coordinate system in to the inertial coordinate system for accounting the Earth rotation. The order of nine terms: (1,1), (2,1), (3,1), (1,2), (2,2), (3,2), (1,3), (2,3), (3,3) Units: 1/s2. |