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 60774. 1.319 -0.449 -2.755
aji 60775. 1.516 -1.387 -3.138
aji 60776. 1.320 -1.696 -2.836
aji 60777. 1.563 -3.242 -3.283
Ajisai SGF - DGF
aji 60774. 0.164 0.959 0.738
aji 60775. 0.084 2.379 1.272
aji 60776. 0.447 3.538 1.530
aji 60777. 0.432 5.855 2.086
aji 60778. 0.485 7.959 2.647
Ajisai ITT - DGF
aji 60774. -1.155 1.408 3.493
aji 60775. -1.432 3.766 4.410
aji 60776. -0.873 5.233 4.366
aji 60777. -1.130 9.097 5.369
Beacon-C SGF - ITT
bec 60774. 0.338 -1.790 10.720
bec 60775. 0.939 -5.697 11.891
bec 60776. 1.462 -10.031 15.752
bec 60777. 1.669 -11.176 17.358
Etalon-1 SGF - ITT
eta 60774. -5.762 11.331 34.004
eta 60775. 5.557 20.383 39.551
eta 60776. 3.128 30.704 45.944
eta 60777. -3.593 37.185 48.535
Etalon-1 SGF - DGF
eta 60774. -12.722 13.753 -3.143
eta 60775. -11.195 14.732 6.674
eta 60776. -11.285 15.495 8.022
eta 60777. -9.336 16.703 4.635
eta 60778. -4.631 19.106 -3.896
Etalon-1 ITT - DGF
eta 60774. -6.960 2.422 -37.147
eta 60775. -16.752 -5.651 -32.877
eta 60776. -14.412 -15.208 -37.922
eta 60777. -5.743 -20.483 -43.899
Etalon-2 SGF - ITT
etb 60774. 7.958 -70.272 -114.177
etb 60775. 8.740 -89.524 -140.361
etb 60776. 16.734 -116.730 -163.008
etb 60777. 43.161 -141.997 -184.354
Etalon-2 SGF - DGF
etb 60774. -2.770 -10.788 0.897
etb 60775. -0.369 -17.622 -0.501
etb 60776. 3.770 -24.598 -2.525
etb 60777. 7.297 -22.222 -10.128
etb 60778. 11.924 -30.164 -11.513
Etalon-2 ITT - DGF
etb 60774. -10.728 59.483 115.074
etb 60775. -9.109 71.902 139.860
etb 60776. -12.965 92.132 160.483
etb 60777. -33.168 111.133 178.898
Larets SGF - ITT
lar 60774. -6.922 37.618 4.351
lar 60775. -8.700 51.267 5.565
lar 60776. -16.251 61.749 10.067
lar 60777. -11.243 90.413 6.764
Larets SGF - DGF
lar 60774. 4.948 -36.020 -0.759
lar 60775. 8.122 -70.058 -1.401
lar 60776. 23.425 -105.548 -10.368
lar 60777. 14.177 -172.697 -3.005
lar 60778. 43.104 -210.895 -14.611
Larets ITT - DGF
lar 60774. 11.871 -73.638 -5.110
lar 60775. 16.822 -121.326 -6.966
lar 60776. 39.676 -167.298 -20.435
lar 60777. 25.420 -263.111 -9.769
LARES SGF - ITT
las 60774. 1.765 1.311 -3.241
las 60775. 1.876 2.945 -3.970
las 60776. 1.791 5.475 -4.902
las 60777. 1.585 7.594 -5.577
LARES SGF - DGF
las 60774. 0.141 0.621 -0.163
las 60775. 0.163 1.135 -0.235
las 60776. 0.259 1.926 -0.314
las 60777. 0.204 2.871 -0.330
las 60778. 0.444 4.251 -0.518
LARES ITT - DGF
las 60774. -1.624 -0.690 3.079
las 60775. -1.712 -1.810 3.735
las 60776. -1.531 -3.550 4.588
las 60777. -1.381 -4.723 5.247
LARES-2 SGF - DGF
la2 60774. -0.012 0.066 0.030
la2 60775. 0.005 0.117 0.045
la2 60776. 0.005 0.131 0.045
la2 60777. -0.032 0.146 0.086
la2 60778. 0.001 0.196 0.081
LAGEOS-1 SGF - ITT
lga 60774. 3.157 -0.091 -1.696
lga 60775. 2.905 0.408 -2.197
lga 60776. 3.030 0.238 -1.837
lga 60777. 3.270 0.125 -1.579
LAGEOS-1 SGF - DGF
lga 60774. 0.001 -0.110 -0.071
lga 60775. -0.002 -0.203 -0.118
lga 60776. -0.040 -0.248 -0.131
lga 60777. 0.063 -0.324 -0.214
lga 60778. -0.075 -0.402 -0.206
LAGEOS-2 SGF - ITT
lgb 60774. 2.560 0.323 -3.999
lgb 60775. 2.598 -0.196 -5.307
lgb 60776. 2.775 -1.468 -4.482
lgb 60777. 2.067 -2.336 -4.285
LAGEOS-2 SGF - DGF
lgb 60774. -0.010 0.053 0.167
lgb 60775. 0.003 0.115 0.113
lgb 60776. -0.015 0.087 0.204
lgb 60777. 0.005 0.192 0.172
lgb 60778. -0.027 0.179 0.230
Stella SGF - ITT
ste 60774. 4.105 6.068 -4.328
ste 60775. 6.535 11.104 -6.371
ste 60776. 6.248 22.151 -6.902
ste 60777. 4.708 32.579 -5.864
Stella SGF - DGF
ste 60774. -0.214 -0.367 -0.009
ste 60775. -0.489 -1.204 0.139
ste 60776. -0.492 -2.787 0.036
ste 60777. 0.001 -3.872 -0.529
ste 60778. 0.148 -4.281 -0.821
Stella ITT - DGF
ste 60774. -4.319 -6.436 4.320
ste 60775. -7.024 -12.309 6.510
ste 60776. -6.740 -24.939 6.938
ste 60777. -4.707 -36.450 5.334
Starlette SGF - ITT
str 60774. 1.417 -10.763 -0.362
str 60775. -0.096 -19.659 1.318
str 60776. 0.701 -31.867 0.852
str 60777. 1.677 -45.114 0.805
Starlette SGF - DGF
str 60774. 0.028 0.993 -0.064
str 60775. 0.227 1.817 -0.161
str 60776. 0.239 3.084 -0.285
str 60777. 0.363 4.990 -0.468
str 60778. 0.249 8.016 -0.577
Starlette ITT - DGF
str 60774. -1.388 11.756 0.298
str 60775. 0.322 21.476 -1.479
str 60776. -0.461 34.951 -1.137
str 60777. -1.464 50.162 -1.173