MODELLING THE EARTH'S ROTATION 
Tabulated models for the Earth orientation / rotation parameters variations  
Useful constants  IERS Conventions
 Models and Softwares  Tidal variations in LOD Compilation done by Ch. Bizouard (Observatoire de Paris) and Laura Fernandez (Facultad de Ciencias Astronomicas y Geofisicas La Plata Argentina). Send your comments to christian.bizouard[at]obspm.fr. Permanent improvements and adds


Useful constants  geodesy, gravimetry, physics, astronomy : click here  
IERS CONVENTIONS  
IERS CONVENTIONS CENTER IERS CONVENTIONS 1996 IERS CONVENTIONS 2003 
Models, constants related to Earth's rotation and adopted by IERS (conventions 2003 is an update of conventions 1996).  
Astronomical and geophysical models with associated softwares  
SOFA: Standards of Fundamental Astronomy (Astronomical Sofware packages recommanded by IAU)  
MODELS  CORRESPONDING SOFTWARE OR SOURCE  
Earth orientation matrix based on Nutation model IAU 2000  Coordinate transformation from the terrestrial reference system (TRS) to the celestial reference system (CRS) using the IAU 2000 precessionnutation model  Non Rotating Origin algorithm Partial derivatives with respect x,y, UT1, X,Y : nro_partialderiv.f 

Nutation model IAU 1980  
Conversion celestial pole offsets UAI 1980  UAI 2000  Package of subroutines in order to convert the IAU 1980 celestial pole offsets (dpsi,deps) into the IAU 2000 celestial pole offsets (dpsi,deps,dX,dY) and reciprocally, based upon SOFA matrix transformation.  uai2000.package readme Contact : christian.bizouard[at]obspm.fr 

Correction for the effect of zonal tides in UT1, LOD and angular velocity,
consistent with the IERS Conventions 2000. 
tver2000.f Contact: christian.bizouard[at]obspm.fr 

Diurnal and semidiurnal
polar motion/UT1  IERS conventions 2000 : PM
caused by oceanic tides (71 waves) and lunisolar
torque (10 waves) 
Interpolation of IERS polar motion and UT1 time series, with restoration of diurnal and semi diurnal variations (developped by Observatoire de Paris/NEOS)  interp.f, interp.readme Contact: christian.bizouard[at]obspm.fr 

TAI  UTC  Computation of the difference TAIUTC from 1 January 1961 untill now. Very usefull for converting UT1UTC into UT1TAI. 
mjd_to_TAIUTC.f 

Compute the civil date from the (modified) Julian Date and reciprocally  caldat.f Contact: gérard.francou@obspm.fr 