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<p class="MsoNormal"><span style="font-family:Courier;color:black">Classification: UNCLASSIFIED<br>
======================================================<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Dear Colleagues,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The NGA Office of Geomatics, GNSS Division has recently published an open-access paper on the WGS 84 Terrestrial Reference Frame (TRF) in the NAVIGATION Journal of the Institute of Navigation (ION). This paper provides information about
historical and current realizations of the WGS 84 TRF, details on current alignment methodology, and an analysis of the accuracy of WGS 84 alignment with respect to ITRF over time. Please see the paper linked below.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><a href="https://navi.ion.org/content/72/2/navi.693">https://navi.ion.org/content/72/2/navi.693</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Precise ephemerides of GPS in the WGS 84 TRF are available under the GNSS tab here:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><a href="https://earth-info.nga.mil/index.php?dir=gnss&action=gnss">https://earth-info.nga.mil/index.php?dir=gnss&action=gnss</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">For more information regarding WGS 84, please visit the NGA Office of Geomatics website linked above.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Best regards,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Office of Geomatics<o:p></o:p></p>
<p class="MsoNormal">GNSS Division, National Geospatial-Intelligence Agency<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Approved for public release, NGA-U-2025-01500<o:p></o:p></p>
<p class="MsoNormal"><span style="font-family:Courier;color:black">======================================================<br>
Classification: UNCLASSIFIED<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Courier;color:black"><o:p> </o:p></span></p>
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