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 60876. 4.246 1.383 -3.895
aji 60877. 4.270 1.983 -3.719
aji 60878. 4.457 2.768 -3.687
aji 60879. 4.519 3.576 -3.487
Ajisai SGF - DGF
aji 60876. 0.269 0.892 0.339
aji 60877. 0.318 1.460 0.563
aji 60878. 0.492 2.365 0.749
aji 60879. 0.503 3.307 0.937
aji 60880. 0.459 4.583 1.144
Ajisai ITT - DGF
aji 60876. -3.977 -0.491 4.234
aji 60877. -3.952 -0.523 4.281
aji 60878. -3.965 -0.403 4.436
aji 60879. -4.016 -0.269 4.424
Beacon-C SGF - ITT
bec 60876. 3.943 27.954 -15.996
bec 60877. 2.667 59.774 -21.306
bec 60878. -0.453 100.966 -26.005
bec 60879. 1.015 151.584 -32.329
Etalon-1 SGF - ITT
eta 60876. 14.818 -15.145 -16.155
eta 60877. 18.387 -16.791 -18.502
eta 60878. 15.850 -9.891 -22.558
eta 60879. 32.728 -17.064 -22.777
Etalon-1 SGF - DGF
eta 60876. 0.072 0.005 0.514
eta 60877. 0.094 0.023 0.620
eta 60878. 0.024 0.090 0.687
eta 60879. -0.224 0.100 0.901
eta 60880. -0.299 -0.239 1.010
Etalon-1 ITT - DGF
eta 60876. -14.747 15.149 16.669
eta 60877. -18.293 16.814 19.122
eta 60878. -15.826 9.981 23.246
eta 60879. -32.714 17.004 23.690
Etalon-2 SGF - ITT
etb 60876. 11.729 -3.154 2.741
etb 60877. 13.302 -4.789 4.404
etb 60878. 15.511 1.230 2.534
etb 60879. 16.126 3.547 2.243
Etalon-2 SGF - DGF
etb 60876. -0.152 0.011 0.327
etb 60877. -0.148 -0.082 0.057
etb 60878. 0.181 0.179 0.063
etb 60879. 0.237 0.366 0.029
etb 60880. 0.296 0.540 -0.042
Etalon-2 ITT - DGF
etb 60876. -11.881 3.165 -2.414
etb 60877. -13.449 4.708 -4.347
etb 60878. -15.330 -1.051 -2.471
etb 60879. -15.890 -3.181 -2.214
Larets SGF - ITT
lar 60876. 6.750 -7.323 -4.962
lar 60877. 6.418 -12.302 -4.850
lar 60878. 7.905 -17.181 -5.851
lar 60879. 7.770 -24.025 -7.603
Larets SGF - DGF
lar 60876. 2.163 -5.139 -2.000
lar 60877. 2.499 -12.324 -2.432
lar 60878. 4.324 -19.485 -3.389
lar 60879. 4.579 -29.546 -5.646
lar 60880. 4.859 -43.755 -5.988
Larets ITT - DGF
lar 60876. -4.587 2.184 2.962
lar 60877. -3.920 -0.022 2.418
lar 60878. -3.580 -2.304 2.462
lar 60879. -3.191 -5.521 1.957
LARES SGF - ITT
las 60876. 5.373 -6.534 -4.479
las 60877. 5.763 -10.176 -5.237
las 60878. 5.249 -14.632 -5.698
las 60879. 7.111 -20.242 -7.737
LARES SGF - DGF
las 60876. 0.080 0.108 -0.149
las 60877. 0.109 0.060 -0.161
las 60878. 0.080 -0.336 -0.211
las 60879. 0.294 -0.695 -0.382
las 60880. 0.060 -1.244 -0.325
LARES ITT - DGF
las 60876. -5.293 6.642 4.330
las 60877. -5.655 10.236 5.076
las 60878. -5.169 14.296 5.487
las 60879. -6.816 19.547 7.354
LARES-2 SGF - DGF
la2 60876. 0.019 0.060 0.016
la2 60877. 0.052 0.100 0.012
la2 60878. 0.043 0.204 0.025
la2 60879. 0.042 0.228 0.070
la2 60880. 0.113 0.354 0.003
LAGEOS-1 SGF - ITT
lga 60876. 8.502 -3.030 -2.316
lga 60877. 7.765 -3.441 -0.217
lga 60878. 10.877 -8.917 -2.595
lga 60879. 8.175 -5.436 0.450
LAGEOS-1 SGF - DGF
lga 60876. -0.028 -0.144 0.023
lga 60877. 0.009 -0.138 -0.014
lga 60878. -0.065 -0.029 0.027
lga 60879. 0.010 -0.111 -0.038
lga 60880. 0.028 -0.029 -0.099
LAGEOS-2 SGF - ITT
lgb 60876. 5.509 -2.781 -2.885
lgb 60877. 4.682 -4.117 -2.573
lgb 60878. 6.145 -7.468 -2.976
lgb 60879. 6.366 -9.938 -4.080
LAGEOS-2 SGF - DGF
lgb 60876. 0.036 -0.047 -0.058
lgb 60877. 0.013 -0.053 -0.012
lgb 60878. 0.057 -0.087 -0.083
lgb 60879. -0.001 -0.087 -0.024
lgb 60880. 0.069 -0.111 -0.046
Stella SGF - ITT
ste 60876. 6.513 1.568 -4.769
ste 60877. 6.554 5.104 -4.705
ste 60878. 5.630 8.662 -3.787
ste 60879. 5.858 11.085 -4.162
Stella SGF - DGF
ste 60876. -0.775 -1.626 0.404
ste 60877. -1.119 -4.052 0.456
ste 60878. -0.691 -7.068 -0.222
ste 60879. -0.749 -9.478 0.015
ste 60880. -1.520 -13.852 0.644
Stella ITT - DGF
ste 60876. -7.288 -3.194 5.173
ste 60877. -7.673 -9.156 5.160
ste 60878. -6.320 -15.730 3.564
ste 60879. -6.607 -20.563 4.177
Starlette SGF - ITT
str 60876. 3.319 7.232 -3.734
str 60877. 3.766 17.570 -4.034
str 60878. 5.362 32.835 -5.479
str 60879. 4.636 53.266 -4.859
Starlette SGF - DGF
str 60876. 0.052 1.215 -0.058
str 60877. 0.116 2.752 -0.199
str 60878. 0.321 4.828 -0.359
str 60879. 0.249 7.370 -0.367
str 60880. 0.422 10.077 -0.638
Starlette ITT - DGF
str 60876. -3.267 -6.017 3.676
str 60877. -3.649 -14.817 3.836
str 60878. -5.041 -28.007 5.120
str 60879. -4.387 -45.896 4.492