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 59274. 1.284 -0.305 -0.968 aji 59275. 1.482 -1.405 -1.403 aji 59276. 1.211 -2.022 -0.799 aji 59277. 1.360 -3.905 -1.003 Ajisai ITT - JAX Ajisai JAX - SGF Beacon-C SGF - ITT bec 59274. -0.138 -2.896 -1.525 bec 59275. -1.610 -8.647 -1.222 bec 59276. -1.865 -20.328 -1.437 bec 59277. -1.451 -37.884 -2.966 Cyrosat-2 ESA - ITT Etalon-1 SGF - ITT eta 59274. 4.639 2.281 -2.185 eta 59275. 3.920 2.228 -0.450 eta 59276. 3.077 2.489 0.229 Etalon-1 SGF - DGF eta 59274. 0.019 0.533 -0.322 eta 59275. -0.040 0.388 -0.554 eta 59276. 0.034 0.444 -0.805 Etalon-1 ITT - DGF eta 59274. -4.620 -1.748 1.863 eta 59275. -3.960 -1.840 -0.105 eta 59276. -3.068 -1.774 -1.302 eta 59277. -3.262 -2.277 -1.424 Etalon-2 SGF - ITT etb 59274. 4.836 0.634 -2.051 etb 59275. 5.238 1.338 -2.367 etb 59276. 5.020 2.484 -2.506 Etalon-2 SGF - DGF etb 59274. 0.066 -0.019 0.032 etb 59275. 0.153 0.003 -0.001 etb 59276. 0.145 0.062 0.034 Etalon-2 ITT - DGF etb 59274. -4.770 -0.653 2.083 etb 59275. -5.085 -1.335 2.367 etb 59276. -4.875 -2.423 2.540 etb 59277. -4.102 -3.200 2.324 Larets SGF - ITT lar 59274. 1.516 -2.765 -1.781 lar 59275. 2.192 -3.703 -2.506 lar 59276. 1.369 -4.561 -2.164 lar 59277. 2.575 -5.007 -3.223 LARES SGF - ITT las 59274. 0.951 -1.297 -0.050 las 59275. 1.279 -2.417 -0.144 las 59276. 0.676 -3.543 0.241 las 59277. 1.322 -5.643 -0.250 LAGEOS-1 SGF - ITT lga 59274. 2.430 0.249 -0.584 lga 59275. 2.959 0.180 -1.059 lga 59276. 2.855 0.597 -0.988 lga 59277. 2.606 0.243 -0.590 LAGEOS-1 ITT - JAX LAGEOS-1 JAX - SGF LAGEOS-1 SGF - DGF lga 59274. 0.005 -0.054 0.034 lga 59275. -0.012 -0.070 0.053 lga 59276. -0.020 -0.104 0.062 lga 59277. 0.009 -0.114 0.070 LAGEOS-2 SGF - ITT lgb 59274. 1.615 0.742 -1.105 lgb 59275. 1.952 0.824 -1.433 lgb 59276. 1.506 0.121 -1.415 lgb 59277. 2.068 0.351 -1.525 LAGEOS-2 ITT - JAX LAGEOS-2 JAX - SGF LAGEOS-2 SGF - DGF lgb 59274. -0.001 -0.011 0.095 lgb 59275. 0.096 -0.108 -0.002 lgb 59276. -0.024 -0.550 0.070 lgb 59277. 0.179 -0.636 -0.016 Stella SGF - ITT ste 59274. 1.672 -0.291 -1.506 ste 59275. 1.367 -1.234 -1.385 ste 59276. 1.127 -3.409 -1.278 ste 59277. 1.604 -5.013 -1.843 Starlette SGF - ITT str 59274. 1.214 -1.038 -2.279 str 59275. 1.183 -3.291 -2.457 str 59276. 2.022 -5.863 -3.452 str 59277. 0.440 -10.010 -1.828