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 58595. 1.184 1.662 -1.434
aji 58596. 1.341 2.762 -1.580
aji 58597. 1.290 4.019 -1.706
aji 58598. 1.131 5.466 -1.819
Ajisai ITT - JAX
aji 58595. -1.243 -1.378 1.581
aji 58596. -1.397 -2.313 1.763
aji 58597. -1.343 -3.412 1.902
Ajisai JAX - SGF
aji 58595. 0.060 -0.285 -0.147
aji 58596. 0.056 -0.449 -0.182
aji 58597. 0.053 -0.607 -0.195
Beacon-C SGF - ITT
bec 58595. 1.433 -9.913 -0.396
bec 58596. 0.967 -15.524 0.078
bec 58597. 0.152 -21.721 0.936
bec 58598. 1.342 -28.697 -0.949
Cyrosat-2 ESA - ITT
cyb 58595. 1.797 -0.693 0.458
cyb 58596. 1.224 -1.206 0.703
cyb 58597. 2.688 -1.802 -0.925
cyb 58598. 1.811 -2.161 -1.011
Etalon-1 SGF - ITT
eta 58595. 5.170 -1.701 -5.008
eta 58596. 5.056 -0.656 -6.200
eta 58597. 5.765 0.341 -8.346
eta 58598. 3.462 -0.912 -3.933
Etalon-2 SGF - ITT
etb 58595. 5.624 3.161 -1.856
etb 58596. 5.967 1.950 -2.254
etb 58597. 5.969 3.861 -2.269
etb 58598. 6.327 5.608 -2.580
Jason-2 SGF - ITT
Jason-2 ITT - CNES
Jason-2 CNES - SGF
Larets SGF - ITT
lar 58595. 1.729 -0.269 -1.032
lar 58596. 1.865 -0.204 -1.142
lar 58597. 1.890 -0.187 -1.210
lar 58598. 1.983 -0.484 -1.442
LARES SGF - ITT
las 58595. 1.845 -1.648 -0.954
las 58596. 1.940 -2.259 -1.143
las 58597. 1.783 -3.048 -1.203
las 58598. 2.275 -4.031 -1.629
LAGEOS-1 SGF - ITT
lga 58595. 2.656 0.345 -0.152
lga 58596. 3.315 0.643 -0.666
lga 58597. 2.541 1.110 -0.177
lga 58598. 2.573 1.039 0.128
LAGEOS-1 ITT - JAX
lga 58595. -2.663 -0.316 0.218
lga 58596. -3.347 -0.577 0.750
lga 58597. -2.548 -1.029 0.263
LAGEOS-1 JAX - SGF
lga 58595. 0.007 -0.029 -0.066
lga 58596. 0.032 -0.066 -0.084
lga 58597. 0.007 -0.081 -0.086
LAGEOS-2 SGF - ITT
lgb 58595. 1.760 2.301 -1.311
lgb 58596. 1.517 3.755 -1.557
lgb 58597. 1.872 4.525 -1.432
lgb 58598. 1.278 5.851 -1.505
LAGEOS-2 ITT - JAX
lgb 58595. -1.665 -2.967 1.285
lgb 58596. -1.339 -4.771 1.472
lgb 58597. -2.055 -6.047 1.471
LAGEOS-2 JAX - SGF
lgb 58595. -0.096 0.666 0.026
lgb 58596. -0.177 1.016 0.085
lgb 58597. -0.035 1.505 0.059
Stella SGF - ITT
ste 58595. 1.226 -2.869 -1.641
ste 58596. 1.618 -4.150 -2.252
ste 58597. 1.425 -4.650 -2.193
ste 58598. 1.379 -5.991 -2.538
Starlette SGF - ITT