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<p class="MsoNormal">Dear IGS Colleagues,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I noticed in our rapid processing that the biases from GPS-51/G20 have jumped.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Digging into this I noticed that we all of a sudden have C2L and C2X data although this is an old BLOCK IIR-A satellite!? These are incapable to transmit these signals. Nevertheless there are at least 40 IGS stations reporting C2L/C2X data
from this satellite. So it seems pretty real. The satellite is flagged as unhealthy and according to the NAGU 2026006 from January 8, 2026, it is officially decommissioning. So no clue what is happening to this satellite. Scientifically it may be interesting
to see if the old satellites can somehow transmit C2L/C2X signals…. The data of the satellite looks fine both 2W and 2L/2X.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">If anybody knows what is going on with the satellite I am very interested to learn about it.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Cheers,<o:p></o:p></p>
<p class="MsoNormal">Tim<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:12.0pt"><b><span style="font-family:"Calibri",sans-serif;mso-ligatures:none;mso-fareast-language:EN-GB">Dr. Tim Springer</span></b><span style="font-family:"Calibri",sans-serif;mso-ligatures:none;mso-fareast-language:EN-GB"><br>
Navigation Engineer<o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-family:"Calibri",sans-serif;mso-ligatures:none;mso-fareast-language:EN-GB">PosiTim UG (haftungsbeschraenkt)
<br>
Navigation Concepts (NSD), OPS-GN <br>
ESOC - European Space Operations Centre <br>
Robert-Bosch-Straße 5, Room S521<br>
64293 Darmstadt, Germany <br>
Tel.: +49 6151 90 2029<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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