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 60766. 1.527 -0.942 -2.361
aji 60767. 1.229 -2.147 -1.990
aji 60768. 1.738 -4.064 -2.620
aji 60769. 2.030 -5.807 -2.872
Ajisai SGF - DGF
aji 60766. -0.093 1.087 0.814
aji 60767. -0.020 2.481 1.180
aji 60768. -0.238 4.732 1.899
aji 60769. 0.216 6.979 2.164
aji 60770. -0.431 10.079 2.965
Ajisai ITT - DGF
aji 60766. -1.619 2.029 3.175
aji 60767. -1.249 4.628 3.169
aji 60768. -1.976 8.796 4.520
aji 60769. -2.447 12.687 5.401
Beacon-C SGF - ITT
bec 60766. -11.326 62.312 -21.912
bec 60767. -19.279 91.065 -32.411
bec 60768. -13.464 131.035 -45.514
bec 60769. -25.191 167.559 -64.101
Etalon-1 SGF - ITT
eta 60766. -29.168 54.305 28.080
eta 60767. 6.863 60.580 45.134
eta 60768. 16.531 84.253 57.846
eta 60769. 0.976 98.879 57.826
Etalon-1 SGF - DGF
eta 60766. -3.132 1.796 2.332
eta 60767. -0.282 1.624 2.506
eta 60768. 1.021 2.885 3.021
eta 60769. 0.931 4.311 2.841
eta 60770. 0.301 5.247 2.312
Etalon-1 ITT - DGF
eta 60766. 26.035 -52.509 -25.748
eta 60767. -7.145 -58.956 -42.628
eta 60768. -15.510 -81.368 -54.825
eta 60769. -0.045 -94.568 -54.985
Etalon-2 SGF - ITT
etb 60766. 4.016 1.861 -0.567
etb 60767. 3.940 2.006 0.408
etb 60768. 3.927 2.315 0.769
etb 60769. 3.764 2.728 0.928
Etalon-2 SGF - DGF
etb 60766. 0.010 0.057 0.226
etb 60767. 0.017 0.047 0.321
etb 60768. -0.001 0.040 0.424
etb 60769. -0.032 0.017 0.498
etb 60770. -0.047 -0.018 0.523
Etalon-2 ITT - DGF
etb 60766. -4.006 -1.804 0.793
etb 60767. -3.923 -1.959 -0.087
etb 60768. -3.928 -2.275 -0.346
etb 60769. -3.796 -2.711 -0.430
Larets SGF - ITT
lar 60766. -7.313 36.302 -0.906
lar 60767. -9.889 71.146 -0.729
lar 60768. -27.299 104.499 10.312
lar 60769. -20.114 178.827 6.297
Larets SGF - DGF
lar 60766. 4.294 -12.203 -4.017
lar 60767. 5.270 -27.360 -5.403
lar 60768. 12.058 -42.083 -11.058
lar 60769. 8.885 -71.122 -10.177
lar 60770. 20.975 -84.579 -19.913
Larets ITT - DGF
lar 60766. 11.607 -48.505 -3.111
lar 60767. 15.159 -98.506 -4.673
lar 60768. 39.357 -146.582 -21.369
lar 60769. 29.000 -249.949 -16.473
LARES SGF - ITT
las 60766. 2.179 1.336 -3.666
las 60767. 2.602 2.197 -4.388
las 60768. 2.316 3.498 -4.957
las 60769. 2.706 4.567 -5.732
LARES SGF - DGF
las 60766. 0.085 1.150 -0.265
las 60767. 0.252 1.581 -0.348
las 60768. 0.039 2.346 -0.299
las 60769. 0.192 2.853 -0.370
las 60770. 0.009 3.671 -0.320
LARES ITT - DGF
las 60766. -2.094 -0.186 3.401
las 60767. -2.350 -0.617 4.040
las 60768. -2.277 -1.151 4.658
las 60769. -2.514 -1.714 5.362
LARES-2 SGF - DGF
la2 60766. 0.017 0.096 -0.011
la2 60767. -0.033 0.136 0.044
la2 60768. -0.012 0.176 0.027
la2 60769. -0.056 0.161 0.057
la2 60770. -0.035 0.233 0.064
LAGEOS-1 SGF - ITT
lga 60766. 2.969 0.890 -1.724
lga 60767. 2.624 1.908 -1.502
lga 60768. 3.680 3.017 -2.391
lga 60769. 4.096 4.130 -2.726
LAGEOS-1 SGF - DGF
lga 60766. -0.007 -0.105 -0.091
lga 60767. -0.010 -0.160 -0.059
lga 60768. 0.020 -0.097 -0.186
lga 60769. -0.077 -0.159 -0.177
lga 60770. 0.029 -0.175 -0.222
LAGEOS-2 SGF - ITT
lgb 60766. 2.314 1.417 -2.515
lgb 60767. 1.765 2.280 -2.887
lgb 60768. 2.520 2.832 -2.741
lgb 60769. 1.975 4.159 -3.204
LAGEOS-2 SGF - DGF
lgb 60766. 0.003 0.129 -0.110
lgb 60767. 0.000 0.152 -0.193
lgb 60768. 0.005 0.155 -0.147
lgb 60769. -0.001 0.193 -0.251
lgb 60770. 0.004 0.225 -0.179
Stella SGF - ITT
ste 60766. 4.236 8.804 -5.951
ste 60767. 5.204 13.751 -7.835
ste 60768. 8.210 20.809 -10.013
ste 60769. 6.276 32.982 -8.067
Stella SGF - DGF
ste 60766. 0.375 0.654 -0.300
ste 60767. 0.820 2.103 -0.832
ste 60768. 1.817 4.734 -1.551
ste 60769. 1.305 9.065 -1.097
ste 60770. 0.633 13.646 -0.641
Stella ITT - DGF
ste 60766. -3.861 -8.150 5.651
ste 60767. -4.384 -11.648 7.003
ste 60768. -6.393 -16.075 8.461
ste 60769. -4.971 -23.917 6.969
Starlette SGF - ITT
str 60766. 1.316 -0.342 -2.136
str 60767. 1.475 1.253 -1.980
str 60768. 1.048 4.224 -1.808
str 60769. 1.593 7.659 -1.839
Starlette SGF - DGF
str 60766. -0.084 4.199 0.130
str 60767. 0.225 7.599 0.096
str 60768. -1.035 12.010 0.421
str 60769. 0.417 16.924 -0.336
str 60770. 0.742 23.292 -0.603
Starlette ITT - DGF
str 60766. -1.399 4.540 2.267
str 60767. -1.251 6.346 2.076
str 60768. -2.083 7.786 2.229
str 60769. -1.177 9.265 1.503