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 58769. 4.960 7.336 -5.697
aji 58770. 5.227 12.069 -5.778
aji 58771. 4.990 18.267 -5.642
aji 58772. 5.336 26.690 -5.704
Ajisai ITT - JAX
aji 58769. -5.059 -7.342 5.758
aji 58770. -5.327 -12.170 5.845
aji 58771. -5.103 -18.432 5.704
Ajisai JAX - SGF
aji 58769. 0.100 0.007 -0.061
aji 58770. 0.100 0.101 -0.067
aji 58771. 0.113 0.164 -0.062
Beacon-C SGF - ITT
bec 58769. 3.256 -7.365 -1.480
bec 58770. 3.901 -15.094 -0.627
bec 58771. 9.213 -19.306 0.047
bec 58772. 5.373 -22.561 4.270
Cyrosat-2 ESA - ITT
Etalon-1 SGF - ITT
Etalon-2 SGF - ITT
Jason-2 SGF - ITT
Jason-2 ITT - CNES
Jason-2 CNES - SGF
Larets SGF - ITT
lar 58769. 5.456 -6.277 -5.803
lar 58770. 6.386 -8.611 -6.780
lar 58771. 6.721 -11.341 -8.386
lar 58772. 8.654 -14.055 -9.332
LARES SGF - ITT
LAGEOS-1 SGF - ITT
lga 58769. 7.508 2.372 -0.767
lga 58770. 8.110 1.886 -0.717
lga 58771. 8.260 1.527 -0.202
lga 58772. 7.957 0.299 0.680
LAGEOS-1 ITT - JAX
lga 58769. -7.501 -2.375 0.675
lga 58770. -8.094 -1.910 0.601
lga 58771. -8.645 -1.850 0.736
LAGEOS-1 JAX - SGF
lga 58769. -0.007 0.002 0.092
lga 58770. -0.016 0.023 0.117
lga 58771. -0.034 0.044 0.148
LAGEOS-2 SGF - ITT
lgb 58769. 5.209 0.819 -5.079
lgb 58770. 7.051 -0.705 -5.931
lgb 58771. 4.615 -1.873 -5.025
lgb 58772. 6.587 -4.320 -7.980
LAGEOS-2 ITT - JAX
lgb 58769. -5.157 -0.656 5.032
lgb 58770. -7.093 0.985 5.872
lgb 58771. -4.846 2.143 4.088
LAGEOS-2 JAX - SGF
lgb 58769. -0.052 -0.163 0.047
lgb 58770. 0.041 -0.280 0.059
lgb 58771. -0.093 -0.368 0.166
Stella SGF - ITT
ste 58769. 5.947 5.411 -2.074
ste 58770. 5.952 7.626 -1.863
ste 58771. 6.000 10.629 -2.078
ste 58772. 6.133 14.527 -2.088
Starlette SGF - ITT
str 58769. 5.685 0.701 0.186
str 58770. 6.151 -0.433 2.293
str 58771. 7.126 -2.249 4.844
str 58772. 7.013 -2.018 6.196