version 2
Source: IERS Bulletin A (2000_2000_2)

Orbits: to be used with the IGS Rapid Service Orbits (IGR)

  MJD      Xpole   Ypole  UT1-UTC    LOD  Xsig  Ysig   UTsig  LODsig  Nr Nf Nt
             (10**-6")       (0.1 usec)    (10**-6")    (0.1 usec)  
51647.50   81871  343369  2635056  10623    34    54     112       0   0  0  0
51648.50   82750  343592  2623894  11701  2117  2128    1556       0   0  0  0
51649.50   83567  343736  2611930  12227  4650  4650    4024       0   0  0  0