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 60104. 2.425 0.876 -1.841
aji 60105. 2.549 4.764 -2.069
aji 60106. 2.968 9.108 -2.384
aji 60107. 2.903 14.642 -2.140
Ajisai SGF - DGF
aji 60104. 0.201 1.292 -0.563
aji 60105. 0.244 3.619 -0.970
aji 60106. 0.464 6.760 -1.502
aji 60107. 0.383 11.139 -1.796
aji 60108. 0.506 17.629 -2.404
Ajisai ITT - DGF
aji 60104. -2.224 0.416 1.278
aji 60105. -2.305 -1.145 1.099
aji 60106. -2.503 -2.348 0.882
aji 60107. -2.520 -3.502 0.344
Beacon-C SGF - ITT
bec 60104. -0.459 -25.439 -1.304
bec 60105. -0.669 -44.293 -1.143
bec 60106. 0.735 -68.231 -2.038
bec 60107. -3.087 -94.536 0.117
Etalon-1 SGF - ITT
eta 60104. -33.989 -64.506 -35.229
eta 60105. 25.236 -92.005 52.589
eta 60106. 87.150 -101.270 -4.574
eta 60107. 99.501 -125.572 -101.400
Etalon-1 SGF - DGF
eta 60104. 0.487 1.091 -0.508
eta 60105. -0.111 1.806 -0.595
eta 60106. -0.575 1.889 -0.234
eta 60107. -0.571 1.977 0.284
Etalon-1 ITT - DGF
eta 60104. 34.476 65.597 34.721
eta 60105. -25.348 93.811 -53.184
eta 60106. -87.726 103.159 4.340
eta 60107. -100.073 127.549 101.685
Etalon-2 SGF - ITT
etb 60104. 12.220 8.567 16.197
etb 60105. 32.977 13.563 6.810
etb 60106. 44.112 49.397 1.572
etb 60107. 24.157 77.988 39.098
Etalon-2 SGF - DGF
etb 60104. -0.015 0.019 0.297
etb 60105. 0.021 0.058 0.203
etb 60106. -0.022 0.223 0.239
etb 60107. -0.065 0.283 0.285
Etalon-2 ITT - DGF
etb 60104. -12.235 -8.549 -15.900
etb 60105. -32.955 -13.505 -6.607
etb 60106. -44.133 -49.175 -1.333
etb 60107. -24.279 -77.686 -38.610
Larets SGF - ITT
lar 60104. 1.962 4.054 3.677
lar 60105. 3.183 8.047 3.964
lar 60106. 3.990 13.247 5.139
lar 60107. -0.412 18.206 9.847
Larets SGF - DGF
lar 60104. -2.886 7.476 1.814
lar 60105. -1.690 14.665 0.647
lar 60106. -0.454 25.069 0.007
lar 60107. -9.511 35.007 6.228
lar 60108. 0.071 52.261 -1.897
Larets ITT - DGF
lar 60104. -4.848 3.423 -1.863
lar 60105. -4.873 6.618 -3.317
lar 60106. -4.444 11.822 -5.132
lar 60107. -9.099 16.801 -3.619
LARES SGF - ITT
las 60104. 2.529 -2.050 -2.723
las 60105. 2.465 -1.376 -3.135
las 60106. 2.466 -0.130 -4.116
las 60107. 1.934 1.034 -4.814
LARES SGF - DGF
las 60104. 0.030 0.646 -0.103
las 60105. 0.002 0.944 -0.131
las 60106. 0.030 1.257 -0.157
las 60107. -0.080 1.600 -0.136
las 60108. 0.001 1.815 -0.185
LARES ITT - DGF
las 60104. -2.499 2.696 2.620
las 60105. -2.463 2.320 3.005
las 60106. -2.436 1.386 3.959
las 60107. -2.014 0.565 4.678
LARES-2 SGF - DGF
la2 60104. 0.015 0.082 -0.223
la2 60105. -0.027 0.116 -0.203
la2 60106. -0.018 0.133 -0.237
la2 60107. 0.000 0.184 -0.241
la2 60108. -0.046 0.190 -0.240
LAGEOS-1 SGF - ITT
lga 60104. 5.421 -2.821 -0.864
lga 60105. 5.221 -1.094 -1.197
lga 60106. 5.765 -2.876 -0.168
lga 60107. 6.495 1.428 -2.148
LAGEOS-1 SGF - DGF
lga 60104. -0.016 -0.080 -0.031
lga 60105. -0.017 -0.069 -0.032
lga 60106. -0.025 -0.109 -0.039
lga 60107. -0.021 -0.054 -0.066
lga 60108. -0.017 -0.020 -0.055
LAGEOS-2 SGF - ITT
lgb 60104. 3.005 -3.306 -3.680
lgb 60105. 4.131 -5.310 -2.979
lgb 60106. 2.711 -5.266 -3.224
lgb 60107. 3.965 -7.060 -5.004
LAGEOS-2 SGF - DGF
lgb 60104. -0.003 0.151 -0.034
lgb 60105. -0.048 0.215 -0.041
lgb 60106. -0.003 0.312 -0.030
lgb 60107. -0.096 0.430 -0.053
lgb 60108. 0.021 0.550 -0.066
Stella SGF - ITT
ste 60104. 3.759 -0.077 -0.668
ste 60105. 3.713 0.955 -0.481
ste 60106. 4.003 2.480 -0.439
ste 60107. 3.858 4.404 -0.180
Stella SGF - DGF
ste 60104. 0.579 0.694 -0.511
ste 60105. 0.999 2.307 -1.000
ste 60106. 1.319 5.158 -1.292
ste 60107. 0.919 8.142 -1.324
ste 60108. 1.222 9.613 -1.487
Stella ITT - DGF
ste 60104. -3.179 0.771 0.156
ste 60105. -2.714 1.352 -0.518
ste 60106. -2.684 2.677 -0.853
ste 60107. -2.939 3.738 -1.143
Starlette SGF - ITT
str 60104. 2.655 1.784 -0.650
str 60105. 3.177 3.197 0.316
str 60106. 3.302 2.403 1.353
str 60107. 4.047 -1.444 2.532
Starlette SGF - DGF
str 60104. 0.113 -1.672 -0.110
str 60105. 0.232 -4.227 -0.510
str 60106. 0.839 -8.388 -0.364
str 60107. -0.114 -14.264 0.326
str 60108. -0.263 -21.661 0.510
Starlette ITT - DGF
str 60104. -2.542 -3.456 0.540
str 60105. -2.945 -7.424 -0.827
str 60106. -2.463 -10.790 -1.717
str 60107. -4.161 -12.820 -2.206