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 60695. 3.183 5.321 -5.434
aji 60696. 3.326 7.857 -5.600
aji 60697. 3.181 11.143 -5.913
aji 60698. 3.243 15.717 -6.189
Ajisai SGF - DGF
aji 60695. 0.545 1.951 0.295
aji 60696. 0.838 5.031 0.516
aji 60697. 0.908 9.328 0.706
aji 60698. 1.440 15.880 0.798
aji 60699. 1.969 22.263 0.883
Ajisai ITT - DGF
aji 60695. -2.639 -3.370 5.729
aji 60696. -2.488 -2.826 6.116
aji 60697. -2.273 -1.814 6.620
aji 60698. -1.803 0.163 6.987
Beacon-C SGF - ITT
bec 60695. -8.651 26.005 -3.438
bec 60696. -12.892 41.736 -6.854
bec 60697. -22.815 61.646 -10.385
bec 60698. -18.340 83.642 -16.436
Etalon-1 SGF - ITT
eta 60695. 4.187 -51.371 3.395
eta 60696. 34.318 -56.354 19.213
eta 60697. 45.352 -29.551 38.259
eta 60698. -11.545 3.118 3.260
Etalon-1 SGF - DGF
eta 60695. 0.581 16.037 5.919
eta 60696. -16.564 26.149 1.445
eta 60697. -31.975 20.345 -18.598
eta 60698. -7.054 14.583 -11.071
eta 60699. 3.290 20.302 -22.062
Etalon-1 ITT - DGF
eta 60695. -3.606 67.407 2.524
eta 60696. -50.882 82.503 -17.769
eta 60697. -77.327 49.896 -56.857
eta 60698. 30.245 21.478 0.066
Etalon-2 SGF - ITT
etb 60695. -41.961 -104.457 -82.667
etb 60696. -5.812 -148.872 -56.874
etb 60697. 58.223 -142.813 -50.726
etb 60698. 27.262 -132.804 -165.941
Etalon-2 SGF - DGF
etb 60695. 3.789 12.695 6.205
etb 60696. 1.827 24.191 -2.341
etb 60697. -13.311 28.971 -12.023
etb 60698. -18.138 33.122 3.800
etb 60699. -24.940 32.438 9.700
Etalon-2 ITT - DGF
etb 60695. 45.750 117.152 88.872
etb 60696. 7.639 173.064 54.533
etb 60697. -71.533 171.784 38.703
etb 60698. -40.638 166.664 182.811
Larets SGF - ITT
lar 60695. 10.815 -19.923 -11.859
lar 60696. 10.886 -39.653 -13.669
lar 60697. 10.529 -66.287 -14.064
lar 60698. 22.239 -86.397 -25.675
Larets SGF - DGF
lar 60695. -13.953 31.254 11.713
lar 60696. -18.682 77.972 17.474
lar 60697. -20.249 150.867 18.106
lar 60698. -52.280 213.533 45.388
lar 60699. -46.342 361.178 44.125
Larets ITT - DGF
lar 60695. -24.768 51.177 23.572
lar 60696. -29.568 117.625 31.143
lar 60697. -30.778 217.154 32.170
lar 60698. -74.520 299.931 71.063
LARES SGF - ITT
las 60695. 3.531 1.087 -3.167
las 60696. 3.484 0.764 -3.113
las 60697. 3.300 -0.334 -3.268
las 60698. 3.139 -0.970 -3.205
LARES SGF - DGF
las 60695. 0.013 0.956 -0.254
las 60696. 0.093 1.314 -0.264
las 60697. 0.059 1.591 -0.214
las 60698. 0.115 1.949 -0.227
las 60699. -0.002 2.302 -0.162
LARES ITT - DGF
las 60695. -3.518 -0.131 2.913
las 60696. -3.391 0.550 2.849
las 60697. -3.241 1.926 3.054
las 60698. -3.036 2.906 2.962
LARES-2 SGF - DGF
la2 60695. 0.072 0.092 -0.303
la2 60696. 0.088 0.070 -0.423
la2 60697. 0.149 0.068 -0.466
la2 60698. 0.090 0.046 -0.531
la2 60699. 0.129 0.023 -0.708
LAGEOS-1 SGF - ITT
lga 60695. 6.822 4.778 -3.087
lga 60696. 6.829 7.116 -3.544
lga 60697. 5.086 6.628 -0.572
lga 60698. 9.582 13.835 -4.744
LAGEOS-1 SGF - DGF
lga 60695. 0.024 -0.210 -0.273
lga 60696. 0.042 -0.288 -0.346
lga 60697. 0.140 -0.308 -0.430
lga 60698. 0.010 -0.473 -0.490
lga 60699. 0.079 -0.521 -0.558
LAGEOS-2 SGF - ITT
lgb 60695. 3.517 3.076 -4.114
lgb 60696. 4.039 4.042 -3.486
lgb 60697. 3.631 5.541 -4.145
lgb 60698. 3.971 6.525 -3.712
LAGEOS-2 SGF - DGF
lgb 60695. 0.032 -0.096 0.045
lgb 60696. 0.016 -0.174 0.093
lgb 60697. 0.018 -0.429 0.083
lgb 60698. -0.002 -0.551 0.136
lgb 60699. -0.042 -1.025 0.173
Stella SGF - ITT
ste 60695. 3.569 3.196 -2.215
ste 60696. 3.612 3.205 -1.767
ste 60697. 3.299 2.996 -1.406
ste 60698. 3.446 3.089 -1.281
Stella SGF - DGF
ste 60695. 1.648 5.946 -0.958
ste 60696. 3.848 10.010 -2.571
ste 60697. 4.740 22.434 -3.360
ste 60698. 4.290 35.354 -3.200
ste 60699. 1.965 48.486 -0.172
Stella ITT - DGF
ste 60695. -1.922 2.750 1.257
ste 60696. 0.236 6.805 -0.804
ste 60697. 1.440 19.438 -1.955
ste 60698. 0.845 32.265 -1.918
Starlette SGF - ITT
str 60695. 3.007 4.899 -6.579
str 60696. 2.480 6.811 -6.929
str 60697. 2.997 8.380 -7.443
str 60698. 2.522 11.634 -7.959
Starlette SGF - DGF
str 60695. 0.245 -4.504 -0.784
str 60696. 1.071 -8.430 -1.328
str 60697. 0.323 -12.822 -0.847
str 60698. 0.729 -19.338 -1.043
str 60699. -0.403 -26.845 -0.311
Starlette ITT - DGF
str 60695. -2.762 -9.404 5.795
str 60696. -1.408 -15.241 5.601
str 60697. -2.674 -21.202 6.596
str 60698. -1.793 -30.971 6.917