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 58409. 4.671 5.750 -6.534
aji 58410. 4.882 8.804 -6.557
aji 58411. 4.734 12.809 -6.512
aji 58412. 4.830 18.301 -6.639
Ajisai ITT - JAX
aji 58409. -4.682 -6.178 6.624
aji 58410. -4.928 -9.480 6.687
aji 58411. -4.804 -13.709 6.651
Ajisai JAX - SGF
aji 58409. 0.011 0.428 -0.090
aji 58410. 0.046 0.675 -0.130
aji 58411. 0.071 0.901 -0.139
Beacon-C SGF - ITT
bec 58409. 6.841 3.428 -1.579
bec 58410. 9.360 5.138 2.994
bec 58411. 12.143 3.755 8.611
bec 58412. 16.733 1.682 14.812
Cyrosat-2 ESA - ITT
cyb 58409. 11.411 2.912 -8.173
cyb 58410. 15.391 7.144 -12.257
cyb 58411. 18.277 16.049 -14.143
cyb 58412. 24.327 25.561 -18.859
Etalon-1 SGF - ITT
eta 58409. 15.020 8.800 -3.990
eta 58410. 13.366 8.883 -5.781
eta 58411. 11.749 7.609 -8.630
eta 58412. 12.623 7.049 -11.807
Etalon-2 SGF - ITT
etb 58409. 15.636 6.489 -18.995
etb 58410. 14.842 7.754 -21.159
etb 58411. 14.496 8.021 -23.385
etb 58412. 15.663 8.403 -25.538
Jason-2 SGF - ITT
jsb 58409. 4.580 -1.599 -5.194
jsb 58410. 4.687 -3.622 -7.042
jsb 58411. 4.572 -5.755 -8.384
jsb 58412. 5.071 -9.806 -11.038
Jason-2 ITT - CNES
jsb 58409. -2.885 6.333 2.940
jsb 58410. -2.221 14.772 4.161
jsb 58411. -0.535 24.318 4.479
jsb 58412. -1.775 40.949 8.504
Jason-2 CNES - SGF
jsb 58409. -1.695 -4.735 2.254
jsb 58410. -2.466 -11.150 2.881
jsb 58411. -4.037 -18.563 3.905
jsb 58412. -5.696 -28.386 4.637
Larets SGF - ITT
lar 58409. 6.771 1.120 -3.010
lar 58410. 7.804 2.265 -3.629
lar 58411. 7.603 2.396 -3.479
lar 58412. 8.454 4.923 -4.316
LARES SGF - ITT
las 58409. 6.324 3.089 -3.135
las 58410. 6.136 4.459 -3.906
las 58411. 7.362 6.361 -5.518
las 58412. 8.477 8.238 -7.201
LAGEOS-1 SGF - ITT
lga 58409. 9.764 4.207 -1.511
lga 58410. 10.105 9.358 -3.058
lga 58411. 8.718 14.272 -2.534
lga 58412. 11.501 11.933 -4.547
LAGEOS-1 ITT - JAX
lga 58409. -9.829 -4.259 1.614
lga 58410. -10.213 -9.657 3.191
lga 58411. -8.755 -14.754 2.615
LAGEOS-1 JAX - SGF
lga 58409. 0.066 0.052 -0.103
lga 58410. 0.108 0.299 -0.133
lga 58411. 0.037 0.482 -0.081
LAGEOS-2 SGF - ITT
lgb 58409. 5.673 0.236 -4.207
lgb 58410. 5.896 -1.773 -5.046
lgb 58411. 5.251 -3.869 -5.194
lgb 58412. 5.978 -6.678 -4.624
LAGEOS-2 ITT - JAX
lgb 58409. -5.676 -0.584 4.043
lgb 58410. -5.788 1.298 4.879
lgb 58411. -6.091 3.289 5.304
LAGEOS-2 JAX - SGF
lgb 58409. 0.002 0.348 0.165
lgb 58410. -0.108 0.475 0.168
lgb 58411. -0.029 0.582 0.227
Stella SGF - ITT
ste 58409. 5.930 2.726 -3.059
ste 58410. 6.137 3.920 -3.552
ste 58411. 6.961 6.837 -4.663
ste 58412. 6.585 9.820 -5.040
Starlette SGF - ITT
str 58409. 3.339 1.628 -4.122
str 58410. 3.394 2.028 -4.291
str 58411. 3.267 2.465 -4.517
str 58412. 3.126 3.818 -4.497