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 58287. 2.925 -7.145 -3.743
aji 58288. 3.997 -12.846 -4.353
aji 58289. 2.237 -20.090 -3.511
aji 58290. 4.596 -28.175 -3.547
Ajisai ITT - JAX
aji 58287. -2.778 4.212 3.826
aji 58288. -3.508 7.710 4.243
aji 58289. -3.356 11.831 4.294
Ajisai JAX - SGF
aji 58287. -0.146 2.933 -0.084
aji 58288. -0.490 5.136 0.110
aji 58289. -0.416 8.039 0.221
Beacon-C SGF - ITT
bec 58287. 2.534 13.797 -4.138
bec 58288. 3.984 41.858 -4.856
bec 58289. -6.936 88.940 -0.523
bec 58290. -5.492 165.608 -1.699
Cyrosat-2 ESA - ITT
cyb 58287. 6.384 -8.440 -8.648
cyb 58288. 4.302 -12.489 -9.076
cyb 58289. 13.126 -19.277 -17.498
cyb 58290. 16.547 -24.332 -24.769
Etalon-1 SGF - ITT
eta 58287. 10.720 -5.267 -10.416
eta 58288. 9.273 -4.532 -6.064
eta 58289. 11.892 -3.547 -11.171
eta 58290. 12.865 -1.927 -14.408
Etalon-2 SGF - ITT
etb 58287. 10.148 -1.381 1.786
etb 58288. 8.723 -1.227 3.413
etb 58289. 8.914 -2.356 5.076
etb 58290. 10.429 -2.371 5.528
Jason-2 SGF - ITT
Jason-2 ITT - CNES
jsb 58287. -0.406 -4.308 0.627
jsb 58288. -2.050 -10.833 2.306
jsb 58289. -14.768 -100.383 15.606
jsb 58290. -19.584 -195.521 18.840
Jason-2 CNES - SGF
Larets SGF - ITT
lar 58287. 1.980 3.596 -1.099
lar 58288. -2.042 12.752 2.391
lar 58289. 0.339 30.643 -0.438
lar 58290. -13.471 51.900 11.669
LARES SGF - ITT
las 58287. 2.950 0.295 0.428
las 58288. 2.130 0.815 1.684
las 58289. 2.539 2.154 2.162
las 58290. 1.650 2.391 3.360
LAGEOS-1 SGF - ITT
lga 58287. 5.213 -3.663 -1.187
lga 58288. 5.463 -5.563 -1.998
lga 58289. 7.077 -6.738 -1.702
lga 58290. 6.272 -7.774 0.039
LAGEOS-1 ITT - JAX
lga 58287. -5.239 3.593 1.319
lga 58288. -5.489 5.417 2.069
lga 58289. -7.141 6.597 2.782
LAGEOS-1 JAX - SGF
lga 58287. 0.026 0.069 -0.132
lga 58288. 0.026 0.146 -0.072
lga 58289. -0.039 0.213 -0.056
LAGEOS-2 SGF - ITT
lgb 58287. 4.251 1.859 -3.054
lgb 58288. 5.758 5.536 -4.386
lgb 58289. 3.012 7.639 -2.395
lgb 58290. 7.962 13.929 -5.622
LAGEOS-2 ITT - JAX
lgb 58287. -4.254 -2.013 3.109
lgb 58288. -5.833 -5.842 4.481
lgb 58289. -2.951 -8.038 2.415
LAGEOS-2 JAX - SGF
lgb 58287. 0.003 0.155 -0.056
lgb 58288. 0.075 0.306 -0.095
lgb 58289. -0.061 0.399 -0.020
Stella SGF - ITT
ste 58287. 4.872 1.536 -2.390
ste 58288. 4.867 3.939 -1.879
ste 58289. 5.284 7.138 -1.849
ste 58290. 5.577 11.199 -1.782
Starlette SGF - ITT
str 58287. 2.600 -6.923 -3.246
str 58288. 1.922 -10.720 -2.512
str 58289. 2.393 -15.798 -3.232
str 58290. 2.198 -21.713 -3.363