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 58720. 5.298 -7.196 -6.039
aji 58721. 4.853 -11.303 -4.716
aji 58722. 6.135 -13.924 -5.609
aji 58723. 5.353 -16.857 -5.486
Ajisai ITT - JAX
aji 58720. -5.400 7.212 6.244
aji 58721. -4.966 11.542 4.880
aji 58722. -6.255 14.229 5.836
Ajisai JAX - SGF
aji 58720. 0.103 -0.015 -0.205
aji 58721. 0.113 -0.240 -0.164
aji 58722. 0.119 -0.305 -0.228
Beacon-C SGF - ITT
bec 58720. 5.963 24.358 3.705
bec 58721. 10.920 52.648 7.615
bec 58722. 7.245 95.567 15.829
bec 58723. 4.857 148.620 26.590
Cyrosat-2 ESA - ITT
Etalon-1 SGF - ITT
eta 58720. 16.185 0.837 -11.285
eta 58721. 15.389 2.931 -15.872
eta 58722. 11.610 4.615 -19.125
eta 58723. 15.460 1.968 -17.277
Etalon-2 SGF - ITT
etb 58720. 13.292 -4.870 -6.291
etb 58721. 13.119 -6.005 -6.484
etb 58722. 12.744 -7.337 -7.450
etb 58723. 13.111 -8.838 -7.899
Jason-2 SGF - ITT
Jason-2 ITT - CNES
jsb 58720. -8.101 3.278 2.167
jsb 58721. -9.404 7.039 -1.259
jsb 58722. -10.752 13.182 -6.384
jsb 58723. -12.248 21.873 -12.431
Jason-2 CNES - SGF
Larets SGF - ITT
lar 58720. 8.124 -5.792 -5.642
lar 58721. 7.176 -8.193 -5.267
lar 58722. 7.712 -9.761 -5.506
lar 58723. 9.005 -10.825 -6.970
LARES SGF - ITT
las 58720. 8.149 -6.311 -6.771
las 58721. 8.119 -7.912 -7.448
las 58722. 9.472 -10.856 -7.654
las 58723. 9.693 -12.914 -8.293
LAGEOS-1 SGF - ITT
lga 58720. 8.741 -1.850 -5.954
lga 58721. 9.936 -1.103 -7.083
lga 58722. 9.334 -1.855 -6.708
lga 58723. 10.020 -3.120 -8.503
LAGEOS-1 ITT - JAX
lga 58720. -8.734 1.794 5.841
lga 58721. -9.909 1.097 6.942
lga 58722. -9.626 1.205 7.343
LAGEOS-1 JAX - SGF
lga 58720. -0.007 0.056 0.113
lga 58721. -0.027 0.006 0.140
lga 58722. -0.015 0.023 0.144
LAGEOS-2 SGF - ITT
lgb 58720. 9.109 8.190 -10.382
lgb 58721. 8.043 13.203 -9.638
lgb 58722. 11.122 21.812 -12.034
lgb 58723. 6.589 30.839 -9.740
LAGEOS-2 ITT - JAX
lgb 58720. -9.261 -9.543 10.501
lgb 58721. -8.013 -14.871 9.639
lgb 58722. -11.444 -24.200 12.278
LAGEOS-2 JAX - SGF
lgb 58720. 0.153 1.352 -0.119
lgb 58721. -0.030 1.667 -0.001
lgb 58722. 0.321 2.388 -0.243
Stella SGF - ITT
ste 58720. 5.757 -0.105 -4.192
ste 58721. 5.767 -0.709 -4.539
ste 58722. 5.856 -1.343 -5.113
ste 58723. 5.892 -1.823 -5.541
Starlette SGF - ITT
str 58720. 4.391 -3.351 -4.515
str 58721. 4.179 -2.828 -3.840
str 58722. 4.716 -1.992 -3.651
str 58723. 4.385 -0.280 -3.131