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 60804. 1.827 0.799 -3.826
aji 60805. 1.709 2.028 -3.860
aji 60806. 1.713 3.555 -4.006
aji 60807. 1.884 5.031 -4.118
Ajisai SGF - DGF
aji 60804. 0.167 0.041 -0.104
aji 60805. 0.116 1.105 -0.179
aji 60806. 0.096 2.338 -0.317
aji 60807. 0.133 3.558 -0.490
aji 60808. -0.071 5.026 -0.625
Ajisai ITT - DGF
aji 60804. -1.660 -0.758 3.722
aji 60805. -1.592 -0.923 3.681
aji 60806. -1.617 -1.218 3.689
aji 60807. -1.751 -1.473 3.628
Beacon-C SGF - ITT
bec 60804. 2.397 4.233 -2.400
bec 60805. 3.146 10.402 -1.953
bec 60806. 3.066 18.219 -0.725
bec 60807. 3.149 27.501 1.114
Etalon-1 SGF - ITT
eta 60804. 36.490 119.056 78.953
eta 60805. -9.839 166.043 150.195
eta 60806. -13.245 209.341 263.803
eta 60807. -73.728 227.325 342.616
Etalon-1 SGF - DGF
eta 60804. 0.217 -10.027 -2.605
eta 60805. 3.565 -11.590 -1.820
eta 60806. 3.482 -12.111 -3.995
eta 60807. 5.027 -12.420 -5.251
eta 60808. 5.881 -11.512 -5.611
Etalon-1 ITT - DGF
eta 60804. -36.272 -129.083 -81.558
eta 60805. 13.404 -177.633 -152.015
eta 60806. 16.727 -221.451 -267.798
eta 60807. 78.755 -239.745 -347.868
Etalon-2 SGF - ITT
etb 60804. -6.092 -55.995 -38.926
etb 60805. -5.247 -80.338 -45.704
etb 60806. 1.019 -110.802 -57.302
etb 60807. 17.680 -144.001 -70.963
Etalon-2 SGF - DGF
etb 60804. 0.079 4.844 -12.443
etb 60805. -0.936 0.646 -11.548
etb 60806. -0.155 -5.069 -11.639
etb 60807. 1.941 -6.927 -17.461
etb 60808. 4.413 -17.006 -13.737
Etalon-2 ITT - DGF
etb 60804. 6.172 60.839 26.483
etb 60805. 4.311 80.985 34.156
etb 60806. -1.174 105.733 45.663
etb 60807. -15.433 133.007 58.187
Larets SGF - ITT
lar 60804. 1.193 3.048 -1.859
lar 60805. 0.926 10.109 -1.924
lar 60806. -1.500 17.488 0.515
lar 60807. -3.696 28.651 0.656
Larets SGF - DGF
lar 60804. -8.246 28.914 7.761
lar 60805. -11.041 62.888 9.131
lar 60806. -25.429 98.910 22.696
lar 60807. -23.611 169.436 18.905
lar 60808. -49.375 198.766 41.783
Larets ITT - DGF
lar 60804. -9.439 25.866 9.620
lar 60805. -11.967 52.779 11.055
lar 60806. -23.929 81.422 22.181
lar 60807. -33.002 126.668 22.664
LARES SGF - ITT
las 60804. 3.621 -0.112 -5.646
las 60805. 3.284 -1.333 -5.015
las 60806. 2.817 -3.643 -4.776
las 60807. 3.103 -6.293 -4.253
LARES SGF - DGF
las 60804. 1.544 -0.410 -3.821
las 60805. 1.562 -1.540 -3.977
las 60806. 1.110 -4.687 -3.691
las 60807. 1.570 -6.991 -3.685
las 60808. 0.132 -12.486 -2.804
LARES ITT - DGF
las 60804. -2.078 -0.298 1.825
las 60805. -1.722 -0.207 1.038
las 60806. -1.707 -1.044 1.086
las 60807. -1.533 -0.697 0.569
LARES-2 SGF - DGF
la2 60804. -0.004 0.152 0.114
la2 60805. 0.007 0.206 0.165
la2 60806. -0.016 0.253 0.204
la2 60807. 0.033 0.262 0.236
la2 60808. -0.024 0.343 0.298
LAGEOS-1 SGF - ITT
lga 60804. 4.099 -1.761 -1.912
lga 60805. 4.325 -1.986 -1.599
lga 60806. 4.014 -1.346 -2.592
lga 60807. 3.912 -1.525 -1.306
LAGEOS-1 SGF - DGF
lga 60804. -0.002 -0.066 0.034
lga 60805. -0.004 -0.077 0.027
lga 60806. 0.005 -0.136 0.006
lga 60807. -0.010 -0.120 0.001
lga 60808. 0.019 -0.159 -0.008
LAGEOS-2 SGF - ITT
lgb 60804. 3.369 -1.125 -3.983
lgb 60805. 3.502 -2.305 -4.350
lgb 60806. 3.458 -2.260 -4.080
lgb 60807. 3.195 -3.233 -5.196
LAGEOS-2 SGF - DGF
lgb 60804. 0.035 0.067 0.062
lgb 60805. 0.090 -0.209 0.000
lgb 60806. 0.043 -0.256 0.106
lgb 60807. 0.141 -0.754 -0.068
lgb 60808. 0.061 -0.854 0.199
Stella SGF - ITT
ste 60804. 2.865 -1.816 -2.961
ste 60805. 3.229 -0.732 -3.196
ste 60806. 3.004 0.504 -3.104
ste 60807. 2.597 1.146 -2.598
Stella SGF - DGF
ste 60804. 0.897 3.661 -0.578
ste 60805. 2.452 6.165 -2.113
ste 60806. 2.035 12.264 -1.767
ste 60807. 1.490 18.948 -0.931
ste 60808. 2.130 25.898 -2.027
Stella ITT - DGF
ste 60804. -1.968 5.477 2.383
ste 60805. -0.777 6.897 1.084
ste 60806. -0.969 11.760 1.337
ste 60807. -1.108 17.802 1.667
Starlette SGF - ITT
str 60804. 1.465 -3.022 -2.705
str 60805. 1.665 -3.892 -2.914
str 60806. 1.715 -5.487 -3.061
str 60807. 1.900 -6.660 -3.214
Starlette SGF - DGF
str 60804. -0.123 -3.920 -0.037
str 60805. -0.307 -8.609 0.083
str 60806. 0.297 -15.173 -0.512
str 60807. 0.261 -22.561 -0.507
str 60808. 1.611 -30.775 -1.381
Starlette ITT - DGF
str 60804. -1.588 -0.898 2.668
str 60805. -1.972 -4.716 2.998
str 60806. -1.418 -9.686 2.550
str 60807. -1.638 -15.900 2.707