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 57929. 2.382 -2.591 -1.989
aji 57930. 3.103 -4.452 -2.298
aji 57931. 2.332 -7.168 -1.470
aji 57932. 3.525 -11.090 -2.232
Ajisai ITT - JAX
aji 57929. -2.291 3.102 2.039
aji 57930. -3.175 5.440 2.569
aji 57931. -2.236 9.049 1.731
Ajisai JAX - SGF
aji 57929. -0.091 -0.511 -0.050
aji 57930. 0.072 -0.988 -0.271
aji 57931. -0.096 -1.881 -0.261
Beacon-C SGF - ITT
bec 57929. 3.369 -2.972 -3.004
bec 57930. 3.811 -13.671 -2.221
bec 57931. 4.172 -33.112 -0.907
bec 57932. 6.368 -61.856 -0.568
Cyrosat-2 ESA - ITT
cyb 57929. 9.460 -1.693 -6.671
cyb 57930. 14.323 2.914 -12.941
cyb 57931. 22.056 15.945 -20.042
cyb 57932. 32.982 25.314 -26.838
Etalon-1 SGF - ITT
eta 57929. 10.074 -7.182 -10.175
eta 57930. 10.759 -9.429 -5.248
eta 57931. 11.911 -7.693 0.665
eta 57932. 14.685 -3.544 -10.641
Etalon-2 SGF - ITT
etb 57929. 12.249 -6.736 -6.215
etb 57930. 9.236 -4.005 -7.435
etb 57931. 7.719 -3.043 -5.639
etb 57932. 14.806 -6.940 -12.824
Jason-2 SGF - ITT
jsb 57929. 4.653 -14.981 -2.332
jsb 57930. 4.504 -32.151 -4.102
jsb 57931. 11.777 -61.303 -6.432
jsb 57932. 2.634 -91.407 -0.898
Jason-2 ITT - CNES
jsb 57929. -0.573 9.955 -4.361
jsb 57930. 0.873 21.235 -5.903
jsb 57931. -2.573 42.199 -6.688
jsb 57932. 3.742 63.396 -12.931
Jason-2 CNES - SGF
jsb 57929. -4.081 5.025 6.693
jsb 57930. -5.377 10.917 10.005
jsb 57931. -9.203 19.104 13.120
jsb 57932. -6.376 28.011 13.829
Larets SGF - ITT
lar 57929. 2.894 -2.340 -1.176
lar 57930. 4.164 -2.492 -2.014
lar 57931. 3.213 -0.412 -1.168
lar 57932. 1.527 3.038 0.505
LARES SGF - ITT
las 57929. 6.771 -10.094 -6.954
las 57930. 8.584 -19.439 -8.804
las 57931. 7.214 -31.753 -12.661
las 57932. 14.904 -47.425 -16.497
LAGEOS-1 SGF - ITT
lga 57929. 7.959 -1.111 -2.111
lga 57930. 6.518 -0.016 -1.977
lga 57931. 8.278 6.999 -0.552
lga 57932. 13.762 12.714 -7.094
LAGEOS-1 ITT - JAX
lga 57929. -7.937 1.159 2.136
lga 57930. -6.529 0.055 2.011
lga 57931. -8.256 -6.900 0.613
LAGEOS-1 JAX - SGF
lga 57929. -0.021 -0.048 -0.025
lga 57930. 0.011 -0.038 -0.034
lga 57931. -0.022 -0.099 -0.061
LAGEOS-2 SGF - ITT
lgb 57929. 4.050 -2.124 -1.919
lgb 57930. 4.366 -4.088 -4.220
lgb 57931. 4.879 -6.637 -2.129
lgb 57932. 5.001 -10.431 -4.577
LAGEOS-2 ITT - JAX
lgb 57929. -3.779 1.113 1.875
lgb 57930. -4.481 2.538 4.044
lgb 57931. -4.525 4.620 2.193
LAGEOS-2 JAX - SGF
lgb 57929. -0.271 1.010 0.044
lgb 57930. 0.115 1.549 0.176
lgb 57931. -0.354 2.017 -0.064
Stella SGF - ITT
ste 57929. 4.676 -0.181 -2.398
ste 57930. 5.826 2.635 -3.574
ste 57931. 7.508 8.428 -5.086
ste 57932. 7.580 15.969 -5.946
Starlette SGF - ITT
str 57929. 2.193 -0.499 -1.746
str 57930. 2.622 2.186 -1.706
str 57931. 2.838 6.646 -1.996
str 57932. 3.360 13.127 -2.312