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 58350. 3.849 4.353 -3.249
aji 58351. 3.628 6.629 -3.167
aji 58352. 3.784 9.468 -3.058
aji 58353. 3.922 12.171 -2.910
Ajisai ITT - JAX
aji 58350. -3.834 -4.155 3.279
aji 58351. -3.660 -6.491 3.278
aji 58352. -3.719 -9.480 3.096
Ajisai JAX - SGF
aji 58350. -0.015 -0.197 -0.031
aji 58351. 0.032 -0.138 -0.111
aji 58352. -0.065 0.012 -0.038
Beacon-C SGF - ITT
bec 58350. 4.019 7.171 5.567
bec 58351. 4.622 12.366 10.155
bec 58352. 4.827 18.226 15.256
bec 58353. 5.188 23.017 20.143
Cyrosat-2 ESA - ITT
cyb 58350. 6.608 -1.526 -13.281
cyb 58351. 9.305 -1.521 -19.704
cyb 58352. 7.992 -1.694 -23.769
cyb 58353. 9.475 -2.743 -31.952
Etalon-1 SGF - ITT
eta 58350. 14.499 -4.780 -7.709
eta 58351. 17.347 -4.446 -7.529
eta 58352. 18.281 -2.800 -7.171
eta 58353. 17.530 -0.432 -6.991
Etalon-2 SGF - ITT
etb 58350. 14.365 4.081 -4.479
etb 58351. 13.499 6.241 -5.050
etb 58352. 11.512 7.424 -4.781
etb 58353. 12.832 7.633 -2.947
Jason-2 SGF - ITT
jsb 58350. 2.678 5.713 -0.958
jsb 58351. 2.420 12.208 -1.486
jsb 58352. 3.237 19.781 -3.480
jsb 58353. 1.037 28.100 -4.000
Jason-2 ITT - CNES
jsb 58350. -3.727 -5.748 -0.455
jsb 58351. -4.176 -9.685 -0.499
jsb 58352. -5.422 -13.432 0.315
jsb 58353. -4.786 -17.474 0.527
Jason-2 CNES - SGF
jsb 58350. 1.049 0.035 1.413
jsb 58351. 1.756 -2.523 1.986
jsb 58352. 2.185 -6.350 3.165
jsb 58353. 3.749 -10.625 3.473
Larets SGF - ITT
lar 58350. 7.371 -0.587 -8.045
lar 58351. 7.514 2.550 -9.455
lar 58352. 8.034 6.199 -9.946
lar 58353. 6.720 10.614 -10.212
LARES SGF - ITT
las 58350. 5.402 -1.097 -3.658
las 58351. 5.351 -0.980 -4.217
las 58352. 5.748 -0.780 -4.749
las 58353. 5.805 -0.281 -5.554
LAGEOS-1 SGF - ITT
lga 58350. 8.030 -0.485 -2.224
lga 58351. 8.152 -1.121 -2.423
lga 58352. 7.545 0.236 -1.126
lga 58353. 7.924 -1.768 -2.828
LAGEOS-1 ITT - JAX
lga 58350. -8.130 0.274 2.223
lga 58351. -8.152 0.687 2.383
lga 58352. -7.855 -0.230 1.500
LAGEOS-1 JAX - SGF
lga 58350. 0.099 0.211 0.000
lga 58351. 0.000 0.434 0.040
lga 58352. 0.183 0.441 -0.249
LAGEOS-2 SGF - ITT
lgb 58350. 5.777 2.193 -4.728
lgb 58351. 5.705 3.824 -2.982
lgb 58352. 5.983 4.706 -4.130
lgb 58353. 5.519 5.920 -2.137
LAGEOS-2 ITT - JAX
lgb 58350. -5.605 -3.399 4.767
lgb 58351. -5.661 -5.002 3.153
lgb 58352. -6.018 -6.937 4.267
LAGEOS-2 JAX - SGF
lgb 58350. -0.173 1.206 -0.039
lgb 58351. -0.044 1.178 -0.171
lgb 58352. -0.065 1.935 0.109
Stella SGF - ITT
ste 58350. 6.823 3.322 -3.663
ste 58351. 8.077 8.154 -4.922
ste 58352. 7.814 13.049 -4.898
ste 58353. 8.159 16.732 -5.083
Starlette SGF - ITT
str 58350. 3.803 -1.809 -4.135
str 58351. 3.862 -6.971 -4.603
str 58352. 3.302 -14.512 -4.889
str 58353. 5.549 -24.205 -4.967