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 59473. 5.738 5.902 -6.715
aji 59474. 5.965 10.405 -6.768
aji 59475. 5.874 15.996 -6.828
aji 59476. 5.658 23.330 -6.899
Ajisai ITT - JAX
Ajisai JAX - SGF
Ajisai SGF - DGF
aji 59473. 0.152 0.573 -0.098
aji 59474. 0.228 2.122 -0.227
aji 59475. 0.224 4.370 -0.390
aji 59476. 0.121 7.684 -0.560
Ajisai ITT - DGF
aji 59473. -5.586 -5.329 6.617
aji 59474. -5.738 -8.283 6.541
aji 59475. -5.650 -11.626 6.438
aji 59476. -5.537 -15.646 6.339
Beacon-C SGF - ITT
bec 59473. 1.952 -6.937 -4.746
bec 59474. 1.862 -16.701 -7.342
bec 59475. -1.740 -34.909 -9.089
bec 59476. 1.068 -65.521 -13.223
Cyrosat-2 ESA - ITT
Etalon-1 SGF - ITT
eta 59473. 3.355 17.423 7.078
eta 59474. 1.720 1.730 25.434
eta 59475. 8.365 -14.768 5.739
Etalon-1 SGF - DGF
eta 59473. 0.564 0.208 0.340
eta 59474. 0.590 0.805 0.028
eta 59475. 0.219 1.306 0.706
Etalon-1 ITT - DGF
eta 59473. -2.790 -17.215 -6.738
eta 59474. -1.131 -0.924 -25.406
eta 59475. -11.842 20.528 -21.796
eta 59476. -10.432 20.859 18.843
Etalon-2 SGF - ITT
etb 59473. 10.413 -5.817 -11.148
etb 59474. 18.390 -5.172 -13.445
etb 59475. 17.046 -4.275 -3.973
Etalon-2 SGF - DGF
etb 59473. 0.076 0.068 -0.221
etb 59474. 0.178 0.033 -0.400
etb 59475. 0.191 0.058 -0.464
Etalon-2 ITT - DGF
etb 59473. -10.337 5.885 10.927
etb 59474. -18.213 5.205 13.044
etb 59475. -25.821 0.129 5.429
etb 59476. -3.216 12.471 -3.767
Larets SGF - ITT
lar 59473. 6.474 -1.066 -6.027
lar 59474. 6.263 -0.061 -6.387
lar 59475. 6.148 2.795 -7.155
lar 59476. 5.185 4.939 -6.738
Larets SGF - DGF
lar 59473. 0.762 -6.381 -0.963
lar 59474. 2.827 -11.864 -2.816
lar 59475. 0.345 -21.275 -0.105
lar 59476. 7.043 -29.028 -6.922
Larets ITT - DGF
lar 59473. -5.711 -5.314 5.064
lar 59474. -3.436 -11.803 3.570
lar 59475. -5.803 -24.070 7.050
lar 59476. 1.858 -33.967 -0.184
LARES SGF - ITT
las 59473. 6.641 3.444 -4.127
las 59474. 7.347 4.119 -4.616
las 59475. 7.282 3.920 -5.159
las 59476. 7.992 2.978 -5.555
LARES SGF - DGF
las 59473. 0.146 0.685 -0.517
las 59474. 0.228 1.114 -0.684
las 59475. 0.152 1.594 -0.767
las 59476. 0.416 2.190 -1.044
LARES ITT - DGF
las 59473. -6.495 -2.759 3.610
las 59474. -7.118 -3.005 3.932
las 59475. -7.130 -2.326 4.392
las 59476. -7.576 -0.788 4.512
LAGEOS-1 SGF - ITT
lga 59473. 9.185 2.483 -1.151
lga 59474. 10.257 3.662 -1.067
lga 59475. 9.243 5.032 -1.158
lga 59476. 8.757 6.653 -1.639
LAGEOS-1 ITT - JAX
LAGEOS-1 JAX - SGF
LAGEOS-1 SGF - DGF
lga 59473. 0.031 -0.047 -0.032
lga 59474. 0.058 -0.087 0.000
lga 59475. 0.041 -0.103 0.044
lga 59476. 0.017 -0.166 0.038
LAGEOS-2 SGF - ITT
lgb 59473. 7.002 0.637 -4.623
lgb 59474. 7.129 -0.510 -5.338
lgb 59475. 7.225 -1.706 -4.620
lgb 59476. 6.919 -1.998 -4.326
LAGEOS-2 ITT - JAX
LAGEOS-2 JAX - SGF
LAGEOS-2 SGF - DGF
lgb 59473. 0.101 -0.167 -0.007
lgb 59474. 0.124 -0.474 -0.122
lgb 59475. 0.187 -0.777 0.027
lgb 59476. 0.059 -1.005 -0.217
Stella SGF - ITT
ste 59473. 6.764 3.078 -3.029
ste 59474. 7.085 4.443 -3.440
ste 59475. 7.284 6.771 -3.534
ste 59476. 7.499 8.595 -3.628
Stella SGF - DGF
ste 59473. 0.688 1.768 -0.539
ste 59474. 0.689 3.511 -0.645
ste 59475. 0.441 4.893 -0.483
ste 59476. 0.650 5.482 -0.746
Stella ITT - DGF
ste 59473. -6.076 -1.310 2.491
ste 59474. -6.396 -0.932 2.795
ste 59475. -6.843 -1.878 3.051
ste 59476. -6.849 -3.113 2.882
Starlette SGF - ITT
str 59473. 4.244 -1.351 -6.309
str 59474. 4.313 -1.286 -6.378
str 59475. 4.306 -0.401 -6.340
str 59476. 4.270 1.954 -6.409
Starlette SGF - DGF
str 59473. -0.001 -0.519 -0.003
str 59474. 0.020 -0.289 -0.034
str 59475. -0.003 0.224 -0.011
str 59476. -0.074 1.088 0.026
Starlette ITT - DGF
str 59473. -4.245 0.832 6.306
str 59474. -4.292 0.997 6.344
str 59475. -4.309 0.625 6.330
str 59476. -4.344 -0.866 6.435