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 60734. 1.617 -0.081 -3.224
aji 60735. 1.377 -0.686 -3.601
aji 60736. 1.628 -1.374 -4.149
Ajisai SGF - DGF
aji 60734. -0.050 4.145 -0.752
aji 60735. 0.342 8.864 -1.396
aji 60736. -1.385 15.179 -1.398
aji 60737. 0.265 23.576 -2.851
aji 60738. -3.098 32.569 -0.892
Ajisai ITT - DGF
aji 60734. -1.667 4.226 2.472
aji 60735. -1.036 9.550 2.205
aji 60736. -2.270 16.869 2.541
Beacon-C SGF - ITT
bec 60734. -4.365 112.917 -38.736
bec 60735. -4.813 183.764 -56.825
bec 60736. -16.069 270.112 -71.912
Etalon-1 SGF - ITT
eta 60734. 5.197 0.858 -10.105
eta 60735. 8.604 -2.330 -7.946
eta 60736. 12.489 9.394 -14.989
Etalon-1 SGF - DGF
eta 60734. -1.543 -1.777 -3.842
eta 60735. 2.374 -5.815 -1.982
eta 60736. 7.585 -3.711 -2.351
eta 60737. 7.699 -0.047 -4.235
eta 60738. 4.367 1.750 -2.620
Etalon-1 ITT - DGF
eta 60734. -6.740 -2.635 6.262
eta 60735. -6.230 -3.485 5.963
eta 60736. -8.058 -9.136 7.782
Etalon-2 SGF - ITT
etb 60734. 7.625 7.923 -5.821
etb 60735. 4.410 11.162 -7.195
etb 60736. 6.764 10.250 -2.230
Etalon-2 SGF - DGF
etb 60734. 0.079 0.245 0.624
etb 60735. 0.035 0.242 0.806
etb 60736. 0.189 0.323 1.215
etb 60737. 0.229 0.517 1.488
etb 60738. 0.095 0.710 1.784
Etalon-2 ITT - DGF
etb 60734. -7.546 -7.678 6.445
etb 60735. -4.375 -10.920 8.001
etb 60736. -6.488 -9.913 3.633
Larets SGF - ITT
lar 60734. 12.842 -49.677 -8.304
lar 60735. 13.450 -76.892 -5.875
lar 60736. 24.418 -106.583 -16.331
Larets SGF - DGF
lar 60734. 7.695 -27.250 -5.526
lar 60735. 10.957 -62.106 -6.745
lar 60736. 24.875 -107.276 -19.607
lar 60737. 23.695 -174.633 -16.415
lar 60738. 54.200 -223.197 -44.668
Larets ITT - DGF
lar 60734. -5.147 22.427 2.777
lar 60735. -2.493 14.786 -0.870
lar 60736. 0.457 -0.693 -3.276
LARES SGF - ITT
las 60734. 1.542 -4.704 -1.783
las 60735. 2.141 -7.800 -3.510
las 60736. 2.123 -12.640 -3.685
LARES SGF - DGF
las 60734. 0.044 0.606 -0.100
las 60735. 0.061 0.963 -0.072
las 60736. 0.003 1.489 -0.139
las 60737. 0.133 1.958 -0.105
las 60738. -0.151 2.557 -0.105
LARES ITT - DGF
las 60734. -1.498 5.310 1.683
las 60735. -2.080 8.764 3.438
las 60736. -2.120 14.129 3.545
LARES-2 SGF - DGF
la2 60734. 0.065 0.134 0.012
la2 60735. 0.103 0.138 -0.023
la2 60736. 0.097 0.130 -0.001
la2 60737. 0.093 0.147 -0.010
la2 60738. 0.125 0.131 -0.025
LAGEOS-1 SGF - ITT
lga 60734. 3.694 3.163 -2.166
lga 60735. 3.866 3.491 -2.574
lga 60736. 3.500 4.802 -2.584
LAGEOS-1 SGF - DGF
lga 60734. -0.002 -0.135 0.021
lga 60735. -0.016 -0.253 0.077
lga 60736. 0.075 -0.503 -0.060
lga 60737. -0.092 -0.677 0.098
lga 60738. 0.045 -0.725 0.156
LAGEOS-2 SGF - ITT
lgb 60734. 2.477 2.343 -2.913
lgb 60735. 2.291 2.152 -3.844
lgb 60736. 2.387 2.286 -3.355
LAGEOS-2 SGF - DGF
lgb 60734. -0.055 -0.204 0.211
lgb 60735. 0.108 -0.370 0.037
lgb 60736. -0.180 -0.902 0.395
lgb 60737. 0.126 -1.111 0.013
lgb 60738. -0.161 -1.940 0.544
Stella SGF - ITT
ste 60734. -0.703 -6.763 0.152
ste 60735. -0.115 -14.004 -0.304
ste 60736. 0.951 -21.974 -1.433
Stella SGF - DGF
ste 60734. -2.444 -4.321 1.993
ste 60735. -3.110 -11.934 2.683
ste 60736. -2.194 -21.598 1.681
ste 60737. -4.709 -28.797 3.945
ste 60738. -9.063 -42.341 5.838
Stella ITT - DGF
ste 60734. -1.741 2.441 1.841
ste 60735. -2.994 2.071 2.987
ste 60736. -3.145 0.377 3.114
Starlette SGF - ITT
str 60734. 1.290 -0.240 -3.401
str 60735. 1.303 -1.183 -3.607
str 60736. 1.484 -1.129 -4.071
Starlette SGF - DGF
str 60734. 0.275 2.310 0.036
str 60735. 0.393 5.510 -0.066
str 60736. 0.195 10.067 0.138
str 60737. -0.511 16.406 0.789
str 60738. 2.858 24.209 -1.013
Starlette ITT - DGF
str 60734. -1.016 2.550 3.437
str 60735. -0.911 6.693 3.541
str 60736. -1.289 11.196 4.209