version 2
Source: Xpole,Ypole,Xrt,Yrt,LOD: weighted average of centres;
        UT1-UTC: integrated from the 5th day prior to Bull. A
                 last non-predicted value.

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

  MJD      Xpole   Ypole  UT1-UTC    LOD  Xsig  Ysig   UTsig  LODsig  Nr Nf Nt    Xrt    Yrt  Xrtsig  Yrtsig
             (10**-6")       (0.1 usec)    (10**-6")     (0.1 usec)              (10**-6"/d)    (10**-6"/d)
51881.50  -81097  341558  1147602   9993   138   245     543     154   0  0  0   -318   1537     67    175
51882.50  -81319  342853  1136983  11245   136   240     552     117   0  0  0   -285   1668     39    124