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Re: [Cbor] [dtn] [EXTERNAL] Re: [EXT] Re: LTC timescale (Re: Question regarding RFC 9171 - How to incorporate "Coordinated Lunar Time")

Carsten Bormann <cabo@tzi.org> Sat, 13 April 2024 06:14 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Sat, 13 Apr 2024 08:14:27 +0200
Cc: "Rieber, Richard R (US 347R)" <richard.r.rieber@jpl.nasa.gov>, "sburleig.sb@gmail.com" <sburleig.sb@gmail.com>, "EXTERNAL-Sipos, Brian J (US 9300-Affiliate)" <brian.sipos@jhuapl.edu>, John Dowdell <john.dowdell.ietf@gmail.com>, DTN WG <dtn@ietf.org>, "cbor@ietf.org" <cbor@ietf.org>
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To: Jorge Amodio <jmamodio@gmail.com>
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Subject: Re: [Cbor] [dtn] [EXTERNAL] Re: [EXT] Re: LTC timescale (Re: Question regarding RFC 9171 - How to incorporate "Coordinated Lunar Time")
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On 12. Apr 2024, at 19:34, Jorge Amodio <jmamodio@gmail.com> wrote:
> 
> Just one quick comment, I'm not buying 100% that spacecraft's internal clocks will have to run exclusively on LTC, that is a very "localized" concept.

Wikipedia tells me that the on-board clocks of the GPS satellites are faster than TAI (and thus GPS time) by 38 microseconds per day [1].  This is in the same ballpark as the ~ 58.7 µs/d that are widely reported for the moon surface (and thus LTC?) [2].  Clearly, we know how to manage these rate differences.

Grüße, Carsten


[1]: https://en.wikipedia.org/wiki/Satellite_navigation
[2]: https://en.wikipedia.org/wiki/Coordinated_Lunar_Time

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