Satellite CPF Predictions
The ILRS network uses CPF orbit predictions provided by mission operators and analysis centres.
The SGF calculates precise satellite orbit predictions daily for most of the ILRS targets and makes these orbits available to other SLR stations internationally. These predictions can be compared in advance to those from other CPF providers so that stations and providers can be confident in their accuracy.
The Consolidated Prediction Format (CPF) is the official format used by the ILRS. It consists of geocentric X, Y, and Z positions at different epochs that can be interpolated for very accurate predictions. Accurate prediction of the positions of the full range of laser-tracked satellites is possible in a single, simple format.
The plots below compare the CPFs when there is more than one provider by taking the differences in metres between the orbital X, Y and Z values at zero hours for today and for the next three or four days.
Full residual plot comparisons are plotted here.

Difference between CPF Providers JD X Y Z Ajisai SGF - ITT aji 60817. 1.763 0.312 -1.999 aji 60818. 1.869 1.821 -2.130 aji 60819. 2.044 3.461 -2.107 aji 60820. 1.721 5.345 -1.895 Ajisai SGF - DGF aji 60817. 0.071 3.081 -0.555 aji 60818. 0.418 7.239 -1.266 aji 60819. 0.526 11.776 -1.760 aji 60820. -0.741 16.995 -1.507 aji 60821. 1.313 26.162 -3.471 Ajisai ITT - DGF aji 60817. -1.692 2.769 1.445 aji 60818. -1.450 5.418 0.864 aji 60819. -1.518 8.315 0.347 aji 60820. -2.335 11.729 0.329 Beacon-C SGF - ITT bec 60817. -2.663 -67.586 1.908 bec 60818. 5.359 -134.017 -2.678 bec 60819. -12.949 -226.894 15.290 bec 60820. -17.648 -335.126 15.258 Etalon-1 SGF - ITT eta 60817. 9.992 4.828 -40.775 eta 60818. 6.865 13.451 -53.081 eta 60819. 0.775 23.666 -74.859 eta 60820. -0.296 3.033 -84.839 Etalon-1 SGF - DGF eta 60817. -0.039 -0.061 0.170 eta 60818. -0.087 -0.090 0.231 eta 60819. -0.084 -0.207 0.305 eta 60820. 0.025 -0.264 0.379 eta 60821. -0.003 -0.170 0.397 Etalon-1 ITT - DGF eta 60817. -10.032 -4.890 40.945 eta 60818. -6.952 -13.542 53.311 eta 60819. -0.859 -23.873 75.165 eta 60820. 0.246 -3.233 85.122 Etalon-2 SGF - ITT etb 60817. 8.824 19.086 53.702 etb 60818. 6.123 -15.343 36.430 etb 60819. 2.715 -18.100 34.654 etb 60820. -9.137 -28.767 32.334 Etalon-2 SGF - DGF etb 60817. -0.042 0.046 -0.010 etb 60818. -0.096 -0.037 -0.029 etb 60819. -0.148 -0.164 -0.012 etb 60820. -0.079 -0.320 -0.012 etb 60821. 0.088 -0.373 -0.036 Etalon-2 ITT - DGF etb 60817. -8.866 -19.041 -53.712 etb 60818. -6.219 15.306 -36.459 etb 60819. -2.863 17.936 -34.666 etb 60820. 9.058 28.447 -32.347 Larets SGF - ITT lar 60817. 2.581 -0.393 0.356 lar 60818. 2.628 2.487 1.146 lar 60819. 1.248 4.850 2.749 lar 60820. 3.108 10.372 2.167 Larets SGF - DGF lar 60817. 0.935 -4.241 -1.272 lar 60818. 1.721 -9.086 -1.749 lar 60819. 3.954 -14.108 -3.910 lar 60820. 2.721 -26.859 -2.565 lar 60821. 7.866 -35.730 -6.061 Larets ITT - DGF lar 60817. -1.646 -3.848 -1.628 lar 60818. -0.907 -11.573 -2.895 lar 60819. 2.706 -18.958 -6.660 lar 60820. -0.386 -37.230 -4.733 LARES SGF - ITT las 60817. 3.292 0.474 -2.396 las 60818. 3.390 0.932 -2.397 las 60819. 3.840 2.070 -2.823 las 60820. 4.252 2.821 -3.205 LARES SGF - DGF las 60817. 0.016 0.260 0.085 las 60818. 0.059 0.275 0.120 las 60819. 0.085 0.268 0.088 las 60820. 0.054 0.261 0.227 las 60821. 0.080 0.314 0.170 LARES ITT - DGF las 60817. -3.276 -0.214 2.481 las 60818. -3.331 -0.658 2.517 las 60819. -3.755 -1.802 2.911 las 60820. -4.197 -2.560 3.432 LARES-2 SGF - DGF la2 60817. -0.010 0.046 -0.008 la2 60818. -0.012 0.036 0.015 la2 60819. -0.014 0.041 0.013 la2 60820. -0.034 0.017 0.002 la2 60821. -0.021 0.038 0.079 LAGEOS-1 SGF - ITT lga 60817. 4.675 -0.287 -0.835 lga 60818. 3.634 1.277 -1.598 lga 60819. 4.226 4.452 0.556 lga 60820. 6.308 4.590 -1.931 LAGEOS-1 SGF - DGF lga 60817. 0.002 -0.187 -0.003 lga 60818. -0.019 -0.232 -0.004 lga 60819. -0.031 -0.351 -0.033 lga 60820. -0.043 -0.327 -0.031 lga 60821. -0.011 -0.426 -0.041 LAGEOS-2 SGF - ITT lgb 60817. 3.626 -5.060 -2.868 lgb 60818. 4.700 -10.231 -2.038 lgb 60819. 4.045 -13.436 -2.378 lgb 60820. 3.495 -20.290 -5.160 LAGEOS-2 SGF - DGF lgb 60817. 0.021 -0.015 -0.041 lgb 60818. 0.024 -0.172 -0.006 lgb 60819. 0.011 -0.240 0.018 lgb 60820. 0.026 -0.540 -0.003 lgb 60821. 0.087 -0.769 -0.049 Stella SGF - ITT ste 60817. 3.866 1.327 -2.146 ste 60818. 3.514 3.189 -1.864 ste 60819. 3.693 5.098 -1.816 ste 60820. 3.726 8.220 -1.898 Stella SGF - DGF ste 60817. 0.235 0.002 -0.302 ste 60818. 0.429 1.173 -0.633 ste 60819. 0.487 2.832 -0.701 ste 60820. 1.043 3.683 -1.353 ste 60821. 0.553 5.934 -1.022 Stella ITT - DGF ste 60817. -3.631 -1.324 1.843 ste 60818. -3.085 -2.015 1.231 ste 60819. -3.205 -2.267 1.115 ste 60820. -3.485 -3.638 1.220 Starlette SGF - ITT str 60817. 1.449 1.099 -2.047 str 60818. 1.222 1.204 -2.012 str 60819. 1.335 3.203 -1.921 str 60820. 1.220 5.180 -1.702 Starlette SGF - DGF str 60817. -0.125 0.963 0.028 str 60818. -0.251 2.124 0.144 str 60819. -0.405 3.879 0.264 str 60820. -0.899 6.578 0.608 str 60821. -0.537 9.975 0.861 Starlette ITT - DGF str 60817. -1.574 -0.136 2.075 str 60818. -1.473 0.919 2.156 str 60819. -1.740 0.676 2.186 str 60820. -1.689 1.297 2.307