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<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier">Dan:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier">Good points, but what you describe seems to me to reflect a
<b>dependence</b> on accurate measurement of time, but not the responsibility for
<b>determining</b> UTC-UT1, TDT, leap seconds, etc. attributes of the time scales. Pages 12 and 13 at the following link (source = CCSDS Time Management WG) define the relevant terms:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier"><a href="https://cwe.ccsds.org/sea/docs/SEA-TIME/Meeting%20Materials/2020/2020-01-09%20teleconference/TimeDef_v2.3.pptx?Web=1">https://cwe.ccsds.org/sea/docs/SEA-TIME/Meeting%20Materials/2020/2020-01-09%20teleconference/TimeDef_v2.3.pptx?Web=1</a>
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier">I guess part of my question about lumping these timing functions with navigation in CCSDS relates to the following questions: If timing (i.e., time transfer, time correlation, time synchronization/distribution)
is within the responsibility of navigation, why has no one in the Navigation Working Group or the CESG ever argued that we are professionally derelict by neglecting to ever propose standards for these functions? Why is a working group in the System Engineering
Area assigned to create standards in these areas?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier">To me the answer is that these timing functions are fundamental for all areas of space missions, not just navigation. The "Rationale" on the definition of "Time Correlation" on p.12 of
the link reflects this.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier">David<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt;font-family:Courier"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">"Oltrogge, Daniel" <doltrogge@agi.com><br>
<b>Date: </b>Sunday, January 12, 2020 at 4:17 AM<br>
<b>To: </b>"Berry, David S (US 3920)" <david.s.berry@jpl.nasa.gov><br>
<b>Subject: </b>[EXTERNAL] RE: "Navigation & Timing"<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">David – </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt">For AGI, if you mean distribution of timing such as UTC-UT1, TDT, leap seconds, etc., then yes absolutely we deal with that. The AGI product line needs those to run properly.</span><o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Segoe UI";color:#1F497D">__________________________</span><o:p></o:p></p>
<p class="MsoNormal">Dan Oltrogge<o:p></o:p></p>
<p class="MsoNormal">Director, Center for Space Standards and Innovation<o:p></o:p></p>
<p class="MsoNormal">Analytical Graphics, Incorporated<o:p></o:p></p>
<p class="MsoNormal">Voice: 719-482-4552 <span style="font-size:13.5pt">҉</span> E-mail:
<a href="mailto:oltrogge@agi.com">oltrogge@agi.com</a><o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"> </span><o:p></o:p></p>
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<p class="MsoNormal"><b>From:</b> MOIMS-NAV-EXEC <moims-nav-exec-bounces@mailman.ccsds.org>
<b>On Behalf Of </b>Berry, David S (US 3920) via MOIMS-NAV-EXEC<br>
<b>Sent:</b> Saturday, January 11, 2020 6:45 PM<br>
<b>To:</b> moims-nav-exec@mailman.ccsds.org<br>
<b>Subject:</b> [MOIMS-NAV-EXEC] "Navigation & Timing"<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif">All:</span><o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif"> </span><o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif">I've been assigned to review a document produced by the CCSDS System Engineering Area called the "Application Support Layer Architectural Description Document" (hereafter, ASL/ADD). This
book abstracts at a high level functions of the MOIMS (Mission Operations & Information Management Services) and SOIS (Spacecraft Onboard Interface Services). Recall that the Navigation Working Group is organized under MOIMS.</span><o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif"> </span><o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif">Within the ASL/ADD, there is a MOIMS function labelled "Navigation and Timing". In my limited experience, the "timing" function is not within the purview of the navigation function; while
navigation is obviously concerned with timing and depends upon its accurate measurement, so is nearly every other space mission function (I can't really think of one that doesn't depend at some level on accurate measurement of time).</span><o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif"> </span><o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif;background:yellow;mso-highlight:yellow">So my question to the members of the Navigation WG: Is "Navigation and Timing" a function in your navigation organization, i.e., is your organization
responsible for time correlation, time distribution, time synchronization, etc.</span><o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif"> </span><o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif">Thanks</span><o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif">David</span><o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif"> </span><o:p></o:p></p>
<p class="MsoPlainText"><span style="font-family:"Calibri",sans-serif"> </span><o:p></o:p></p>
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