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 60631. 5.060 5.885 -5.538
aji 60632. 5.383 12.188 -5.351
aji 60633. 5.945 19.480 -5.186
aji 60634. 5.498 28.812 -4.479
Ajisai SGF - DGF
aji 60631. 0.181 3.374 -0.753
aji 60632. 0.230 7.351 -1.188
aji 60633. 0.543 12.018 -1.816
aji 60634. 0.143 17.911 -2.052
aji 60635. 0.071 26.132 -2.762
Ajisai ITT - DGF
aji 60631. -4.879 -2.511 4.784
aji 60632. -5.154 -4.837 4.163
aji 60633. -5.402 -7.463 3.370
aji 60634. -5.356 -10.901 2.427
Beacon-C SGF - ITT
bec 60631. -10.614 47.761 -3.425
bec 60632. -8.634 91.109 -8.169
bec 60633. -15.623 134.673 -7.641
bec 60634. -25.424 183.448 -6.259
Etalon-1 SGF - ITT
eta 60631. 13.943 -0.323 -1.468
eta 60632. 15.300 3.270 -2.196
eta 60633. 13.877 10.073 0.219
eta 60634. 17.857 10.837 -8.958
Etalon-1 SGF - DGF
eta 60631. 0.061 0.058 0.107
eta 60632. 0.099 0.177 0.170
eta 60633. 0.062 0.406 0.317
eta 60634. -0.001 0.483 0.338
Etalon-1 ITT - DGF
eta 60631. -13.882 0.381 1.575
eta 60632. -15.202 -3.093 2.367
eta 60633. -13.815 -9.667 0.098
eta 60634. -17.743 -10.415 9.164
Etalon-2 SGF - ITT
etb 60631. 22.337 2.310 20.969
etb 60632. 22.939 2.602 25.859
etb 60633. 13.091 -1.402 -1.404
etb 60634. 10.764 14.578 39.215
Etalon-2 SGF - DGF
etb 60631. 0.103 -0.033 -0.008
etb 60632. 0.022 0.034 -0.020
etb 60633. -0.119 -0.080 -0.157
etb 60634. -0.112 -0.129 -0.058
Etalon-2 ITT - DGF
etb 60631. -22.234 -2.343 -20.977
etb 60632. -22.917 -2.568 -25.879
etb 60633. -13.211 1.321 1.246
etb 60634. -10.903 -14.548 -39.117
Larets SGF - ITT
lar 60631. 7.005 -1.188 -2.109
lar 60632. 7.210 -2.699 -1.258
lar 60633. 7.399 -4.139 -0.140
lar 60634. 8.541 -6.934 -1.054
Larets SGF - DGF
lar 60631. -5.519 13.098 5.750
lar 60632. -5.964 26.454 6.856
lar 60633. -7.735 41.324 6.530
lar 60634. -12.591 64.676 15.218
lar 60635. -9.082 90.272 11.499
Larets ITT - DGF
lar 60631. -12.524 14.285 7.858
lar 60632. -13.174 29.153 8.114
lar 60633. -15.134 45.463 6.671
lar 60634. -21.132 71.611 16.272
LARES SGF - ITT
las 60631. 4.208 4.355 -0.968
las 60632. 3.417 6.204 -0.903
las 60633. 3.423 8.360 -0.691
las 60634. 2.565 11.182 -0.951
LARES SGF - DGF
las 60631. 0.066 0.597 -0.132
las 60632. -0.006 0.763 -0.123
las 60633. 0.051 0.868 -0.197
las 60634. 0.033 1.137 -0.221
las 60635. 0.069 1.395 -0.290
LARES ITT - DGF
las 60631. -4.142 -3.758 0.836
las 60632. -3.423 -5.441 0.780
las 60633. -3.372 -7.492 0.494
las 60634. -2.532 -10.045 0.730
LARES-2 SGF - DGF
la2 60631. 0.019 0.140 -0.018
la2 60632. -0.003 0.205 -0.014
la2 60633. 0.043 0.239 -0.039
la2 60634. 0.025 0.422 -0.027
la2 60635. -0.008 0.415 0.000
LAGEOS-1 SGF - ITT
lga 60631. 9.646 3.851 -3.114
lga 60632. 11.420 5.024 -2.879
lga 60633. 9.549 13.476 -2.326
lga 60634. 8.752 17.179 -1.896
LAGEOS-1 SGF - DGF
lga 60631. -0.013 -0.142 0.060
lga 60632. -0.029 -0.164 0.069
lga 60633. -0.010 -0.183 0.097
lga 60634. -0.077 -0.212 0.086
lga 60635. -0.049 -0.301 0.118
LAGEOS-2 SGF - ITT
lgb 60631. 8.250 -5.076 -6.989
lgb 60632. 6.181 -9.712 -6.110
lgb 60633. 10.753 -16.965 -6.018
lgb 60634. 10.192 -22.184 -6.664
LAGEOS-2 SGF - DGF
lgb 60631. -0.012 0.185 -0.038
lgb 60632. 0.037 0.236 -0.049
lgb 60633. -0.040 0.355 -0.050
lgb 60634. 0.070 0.355 -0.085
lgb 60635. -0.045 0.497 -0.072
Stella SGF - ITT
ste 60631. 5.176 -0.456 0.176
ste 60632. 4.999 -0.344 1.098
ste 60633. 5.036 -0.245 1.721
ste 60634. 4.855 -0.023 2.434
Stella SGF - DGF
ste 60631. 0.892 2.778 -0.641
ste 60632. 1.451 4.907 -1.036
ste 60633. 1.812 8.346 -1.275
ste 60634. 1.294 12.422 -1.105
ste 60635. 1.131 17.071 -0.746
Stella ITT - DGF
ste 60631. -4.284 3.234 -0.817
ste 60632. -3.548 5.251 -2.134
ste 60633. -3.224 8.591 -2.997
ste 60634. -3.561 12.445 -3.540
Starlette SGF - ITT
str 60631. 4.189 -7.316 -5.275
str 60632. 4.072 -13.687 -5.155
str 60633. 3.433 -19.371 -3.834
str 60634. 4.684 -25.925 -4.995
Starlette SGF - DGF
str 60631. 0.120 0.004 0.012
str 60632. 0.303 0.649 -0.096
str 60633. 0.536 2.610 -0.298
str 60634. 0.513 5.972 -0.403
str 60635. 1.165 11.231 -0.886
Starlette ITT - DGF
str 60631. -4.069 7.320 5.287
str 60632. -3.769 14.337 5.059
str 60633. -2.897 21.982 3.536
str 60634. -4.170 31.897 4.591