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 60665. 3.928 -1.022 -4.696
aji 60666. 3.659 -2.415 -4.472
aji 60667. 3.924 -4.852 -5.227
aji 60668. 4.104 -6.495 -4.736
Ajisai SGF - DGF
aji 60665. -0.609 2.930 0.360
aji 60666. -0.683 6.780 0.209
aji 60667. -1.130 12.657 1.162
aji 60668. -1.951 18.723 0.740
aji 60669. -1.919 26.364 0.766
Ajisai ITT - DGF
aji 60665. -4.538 3.952 5.057
aji 60666. -4.342 9.195 4.681
aji 60667. -5.054 17.509 6.389
aji 60668. -6.055 25.218 5.476
Beacon-C SGF - ITT
bec 60665. -0.810 -18.476 -7.733
bec 60666. -2.128 -33.504 -9.220
bec 60667. -3.069 -52.965 -12.011
bec 60668. -5.856 -74.291 -13.295
Etalon-1 SGF - ITT
eta 60665. 12.668 2.032 -1.337
eta 60666. 15.703 2.578 7.126
eta 60667. 11.617 2.491 12.388
eta 60668. 9.593 -0.139 13.002
Etalon-1 SGF - DGF
eta 60665. 0.057 -0.317 1.145
eta 60666. 0.642 -0.417 2.160
eta 60667. 0.071 -0.531 2.923
eta 60668. -0.220 -1.035 3.160
eta 60669. -0.074 -1.221 3.380
Etalon-1 ITT - DGF
eta 60665. -12.611 -2.348 2.481
eta 60666. -15.061 -2.995 -4.966
eta 60667. -11.546 -3.022 -9.465
eta 60668. -9.900 -1.030 -9.943
Etalon-2 SGF - ITT
etb 60665. 11.911 -0.561 -4.295
etb 60666. 11.999 -0.315 -3.348
etb 60667. 12.979 1.956 -1.458
etb 60668. 13.284 3.753 -1.067
Etalon-2 SGF - DGF
etb 60665. -0.022 0.102 0.163
etb 60666. -0.084 0.158 0.130
etb 60667. -0.121 0.156 0.182
etb 60668. -0.138 0.166 0.271
etb 60669. -0.149 0.157 0.284
Etalon-2 ITT - DGF
etb 60665. -11.933 0.663 4.458
etb 60666. -12.084 0.474 3.478
etb 60667. -13.100 -1.800 1.641
etb 60668. -13.422 -3.586 1.338
Larets SGF - ITT
lar 60665. 0.156 24.929 0.851
lar 60666. -6.399 41.331 5.989
lar 60667. -5.579 69.927 6.122
lar 60668. -18.601 86.209 16.620
Larets SGF - DGF
lar 60665. 0.225 -4.993 0.899
lar 60666. 1.847 -10.051 0.743
lar 60667. 1.662 -18.527 1.808
lar 60668. 3.412 -25.969 2.765
lar 60669. 3.315 -38.473 1.845
Larets ITT - DGF
lar 60665. 0.068 -29.922 0.049
lar 60666. 8.246 -51.382 -5.246
lar 60667. 7.241 -88.454 -4.314
lar 60668. 23.596 -110.788 -16.583
LARES SGF - ITT
las 60665. 3.657 2.293 -3.982
las 60666. 3.584 2.910 -4.193
las 60667. 2.985 4.021 -4.328
las 60668. 2.904 5.481 -4.818
LARES SGF - DGF
las 60665. 0.054 0.660 0.027
las 60666. 0.053 0.845 0.051
las 60667. 0.029 1.142 0.088
las 60668. 0.099 1.382 0.101
las 60669. 0.101 1.753 0.134
LARES ITT - DGF
las 60665. -3.603 -1.633 4.009
las 60666. -3.531 -2.065 4.244
las 60667. -2.956 -2.879 4.416
las 60668. -2.806 -4.099 4.920
LARES-2 SGF - DGF
la2 60665. 0.033 0.074 -0.013
la2 60666. -0.009 0.070 0.005
la2 60667. 0.051 0.175 -0.021
la2 60668. -0.036 0.237 0.027
la2 60669. 0.018 0.223 -0.029
LAGEOS-1 SGF - ITT
lga 60665. 7.933 4.259 -3.242
lga 60666. 8.928 6.389 -3.263
lga 60667. 8.764 13.485 -4.616
lga 60668. 8.022 14.189 -4.268
LAGEOS-1 SGF - DGF
lga 60665. -0.020 -0.206 -0.042
lga 60666. -0.034 -0.273 -0.044
lga 60667. -0.050 -0.425 -0.047
lga 60668. -0.002 -0.319 -0.080
lga 60669. -0.128 -0.617 -0.034
LAGEOS-2 SGF - ITT
lgb 60665. 5.288 1.141 -6.543
lgb 60666. 5.275 2.147 -5.564
lgb 60667. 4.838 2.264 -7.307
lgb 60668. 5.166 3.050 -6.518
LAGEOS-2 SGF - DGF
lgb 60665. 0.022 0.153 0.018
lgb 60666. 0.041 0.208 0.045
lgb 60667. -0.008 0.357 0.052
lgb 60668. 0.064 0.383 0.065
lgb 60669. -0.033 0.586 0.084
Stella SGF - ITT
ste 60665. 5.723 6.281 -5.155
ste 60666. 6.714 8.261 -5.846
ste 60667. 6.907 13.884 -6.451
ste 60668. 6.529 19.773 -6.755
Stella SGF - DGF
ste 60665. 0.042 -0.742 0.629
ste 60666. 0.092 -0.494 0.556
ste 60667. 0.136 0.018 0.582
ste 60668. -0.072 0.409 0.696
ste 60669. -0.339 0.155 0.967
Stella ITT - DGF
ste 60665. -5.681 -7.023 5.784
ste 60666. -6.623 -8.754 6.402
ste 60667. -6.771 -13.866 7.032
ste 60668. -6.601 -19.364 7.451
Starlette SGF - ITT
str 60665. 3.598 -0.733 -6.110
str 60666. 3.445 1.437 -6.163
str 60667. 3.157 5.784 -6.288
str 60668. 3.119 11.926 -6.609
Starlette SGF - DGF
str 60665. -0.023 0.561 -0.023
str 60666. -0.014 2.512 -0.021
str 60667. -0.096 5.743 0.191
str 60668. -0.229 9.730 -0.195
str 60669. 0.250 15.433 -0.138
Starlette ITT - DGF
str 60665. -3.621 1.294 6.087
str 60666. -3.460 1.075 6.142
str 60667. -3.253 -0.041 6.479
str 60668. -3.348 -2.196 6.414