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 60518. 3.536 -10.362 -4.444
aji 60519. 3.680 -15.455 -4.622
aji 60520. 3.043 -21.290 -3.775
aji 60521. 3.859 -30.271 -4.051
Ajisai SGF - DGF
aji 60518. 0.461 3.708 0.226
aji 60519. 0.496 6.929 0.529
aji 60520. 0.854 10.635 0.406
aji 60521. 0.631 16.184 0.676
aji 60522. 1.368 21.738 0.545
Ajisai ITT - DGF
aji 60518. -3.075 14.069 4.670
aji 60519. -3.184 22.384 5.151
aji 60520. -2.189 31.926 4.180
aji 60521. -3.228 46.455 4.727
Beacon-C SGF - ITT
bec 60518. -10.663 -211.984 1.123
bec 60519. -24.744 -343.996 8.781
bec 60520. -18.557 -499.496 6.504
Etalon-1 SGF - ITT
eta 60518. 35.130 -133.330 -88.356
eta 60519. 59.997 -157.354 -107.803
eta 60520. 92.543 -161.897 -131.322
eta 60521. 110.641 -133.995 -156.228
Etalon-1 SGF - DGF
eta 60518. -0.891 4.804 0.861
eta 60519. -1.852 5.809 1.810
eta 60520. -3.160 6.241 2.958
eta 60521. -3.618 5.198 4.541
Etalon-1 ITT - DGF
eta 60518. -36.021 138.134 89.217
eta 60519. -61.849 163.163 109.613
eta 60520. -95.703 168.139 134.279
eta 60521. -114.718 139.508 160.469
Etalon-2 SGF - ITT
etb 60518. 19.486 5.575 -12.385
etb 60519. 12.420 23.466 -8.782
etb 60520. 1.850 25.358 -0.686
etb 60521. 10.916 3.729 6.690
Etalon-2 SGF - DGF
etb 60518. 4.741 2.693 0.291
etb 60519. -0.841 5.862 5.961
etb 60520. -10.255 2.662 1.600
etb 60521. 0.144 6.567 -6.887
Etalon-2 ITT - DGF
etb 60518. -14.744 -2.882 12.677
etb 60519. -13.261 -17.604 14.743
etb 60520. -12.105 -22.697 2.286
etb 60521. 4.689 20.540 -22.969
Larets SGF - ITT
lar 60518. 0.487 9.541 -0.475
lar 60519. 1.364 22.393 -0.382
lar 60520. 3.134 38.687 -2.157
lar 60521. -7.727 54.118 5.715
Larets SGF - DGF
lar 60518. 10.553 -28.306 -9.533
lar 60519. 12.031 -63.645 -12.288
lar 60520. 9.574 -113.342 -9.577
lar 60521. 41.841 -162.200 -35.518
lar 60522. 18.659 -254.067 -20.840
Larets ITT - DGF
lar 60518. 10.066 -37.847 -9.057
lar 60519. 10.668 -86.038 -11.906
lar 60520. 6.440 -152.029 -7.420
lar 60521. 49.567 -216.318 -41.233
LARES SGF - ITT
las 60518. 4.605 -3.518 0.903
las 60519. 4.565 -4.738 3.165
las 60520. 4.835 -6.717 5.696
las 60521. 4.654 -8.937 8.772
LARES SGF - DGF
las 60518. 0.086 0.783 -0.069
las 60519. 0.053 1.078 -0.078
las 60520. 0.162 1.649 -0.126
las 60521. 0.096 2.238 -0.102
las 60522. 0.242 3.136 -0.193
LARES ITT - DGF
las 60518. -4.520 4.301 -0.972
las 60519. -4.513 5.816 -3.244
las 60520. -4.673 8.366 -5.822
las 60521. -4.558 11.174 -8.875
LARES-2 SGF - DGF
la2 60518. 0.017 0.128 0.001
la2 60519. 0.018 0.142 0.018
la2 60520. -0.022 0.167 0.049
la2 60521. 0.025 0.185 0.047
la2 60522. 0.001 0.182 0.067
LAGEOS-1 SGF - ITT
lga 60518. 5.918 -4.974 1.296
lga 60519. 7.167 -6.760 1.600
lga 60520. 4.140 -8.127 5.646
lga 60521. 7.431 -12.536 2.649
LAGEOS-1 SGF - DGF
lga 60518. -0.002 -0.064 0.049
lga 60519. -0.004 -0.124 0.078
lga 60520. -0.039 -0.218 0.138
lga 60521. -0.002 -0.296 0.137
lga 60522. 0.033 -0.384 0.153
LAGEOS-2 SGF - ITT
lgb 60518. 3.316 4.994 -2.033
lgb 60519. 9.484 14.916 -6.837
lgb 60520. 1.476 18.635 -0.405
lgb 60521. 9.270 35.930 -6.160
LAGEOS-2 SGF - DGF
lgb 60518. 0.016 -0.017 -0.050
lgb 60519. -0.053 -0.178 0.088
lgb 60520. 0.050 -0.129 -0.102
lgb 60521. -0.043 -0.317 0.036
lgb 60522. -0.010 -0.265 -0.096
Stella SGF - ITT
ste 60518. 5.446 2.110 -3.749
ste 60519. 5.096 5.321 -3.197
ste 60520. 6.324 6.235 -3.944
ste 60521. 6.814 12.029 -4.433
Stella SGF - DGF
ste 60518. -1.297 -3.180 1.867
ste 60519. -1.184 -6.464 1.494
ste 60520. -2.233 -8.315 2.176
ste 60521. -3.133 -15.047 2.737
ste 60522. -2.504 -21.982 2.072
Stella ITT - DGF
ste 60518. -6.742 -5.289 5.617
ste 60519. -6.280 -11.785 4.691
ste 60520. -8.556 -14.550 6.120
ste 60521. -9.946 -27.076 7.170
Starlette SGF - ITT
str 60518. 3.749 3.940 -4.178
str 60519. 3.299 6.055 -3.573
str 60520. 2.684 9.585 -3.014
str 60521. 3.308 11.724 -3.127
Starlette SGF - DGF
str 60518. 0.346 1.471 -0.145
str 60519. 0.182 3.845 -0.172
str 60520. -0.296 7.561 0.127
str 60521. 0.009 12.129 -0.064
str 60522. -0.561 17.334 0.421
Starlette ITT - DGF
str 60518. -3.403 -2.469 4.033
str 60519. -3.117 -2.210 3.401
str 60520. -2.980 -2.024 3.141
str 60521. -3.298 0.405 3.063