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List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-orgmode-bounces+larch=yhetil.org@gnu.org Sender: emacs-orgmode-bounces+larch=yhetil.org@gnu.org X-Migadu-Country: US X-Migadu-Flow: FLOW_IN ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1674776497; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references:list-id:list-help:list-unsubscribe: list-subscribe:list-post:dkim-signature; bh=joUu6UOqSUYfo7crsn4C8CcreRCdj8t42SCVriLE8ms=; b=V+mmAiC6Kc78k9cmvH7QsZD1BmYcWEzRFLellwLwLt0dup1VkttbtRuuZ2b+2D8IaHA5JL uoxeY6093uEjkK+AG2sU52Ea9ncaZowKe9kHFuSR09YTFXrzniSmWM6qQnR2glvyFxj1YF pHG7frBPWyzzTaUxeqGV0V2q6WyID2O0Ddsj1DkOBaApXeYAzLt4aJRkQiiQmdIGL/fV4N l3Zqk8O4QDAXkJxBNvJ0XkVcz9IssrLHW2WS37ChR6zCD571Dh3fOkvSOXyuwmwAztkKqh lkDEi2iWSkoPBmz2sVIMYUgeFCQv3j//IStnqN1WMogKAoF1UPg319OLqeyf5Q== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=pass header.d=gmail.com header.s=20210112 header.b="BP7Il/hc"; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (aspmx1.migadu.com: domain of "emacs-orgmode-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="emacs-orgmode-bounces+larch=yhetil.org@gnu.org" ARC-Seal: i=1; s=key1; d=yhetil.org; t=1674776497; a=rsa-sha256; cv=none; b=UwjD1jycQSTy7aFDGtK5l7gjHriUwDM7tCnyEW7r6c5m2oM1IPY+lineNkuBjaO5KxgWK8 oAl8hP5yXkNBIyqRkXWK6PMfAN8P9oRuF3bW1x0bgwlASlLoTrgT3Vd3Jk6MZmgMm6suPN BQu8KVJaOEembFd+LGsM8iV8f4fX7tEYl2AlMp5VtR406CELxMuE3YSYezA1poQ2oMfPVw fxZ//+a9W0MdeL9sJwtKFQWRGURgRnvZL9h63FSRNbwrcV/6OteAhMsKK2km+e4LLw1Jsq YzZJozyJVvig39+JSIIcSoAzmksDVfJ3GHHkuY+v9jDK6REpd5FQHcM14I1NRw== X-Spam-Score: -4.75 X-Migadu-Spam-Score: -4.75 Authentication-Results: aspmx1.migadu.com; dkim=pass header.d=gmail.com header.s=20210112 header.b="BP7Il/hc"; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (aspmx1.migadu.com: domain of "emacs-orgmode-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="emacs-orgmode-bounces+larch=yhetil.org@gnu.org" X-Migadu-Queue-Id: D001F312F2 X-Migadu-Scanner: scn1.migadu.com X-TUID: IeSyHId1W4d0 Oh boy. In short, I think we can only hope they come up with LTC and we already have a syntactic space to say whether our reference seconds are TAI/UTC/LTC/MTC/JTC etc. And being the privileged squats that we are if the time system is left out then it means UTC. The friendly thing to do would be to always include the time system code in our timestamps, but I don't think those have standard reference codes yet? > would gain about 56 microseconds over 24 hours And here I was naively hoping to avoid having to deal with relativistic effects. That would seem to be a pretty serious issue, but my assumption further down that comment is hopefully what they will do. Specifically: > let's just assume that clock synchonization will happen between earth and > mars so that the unix epoch could be synchronized between the frames The only generalized solution is to record the full location (see intro to http://naggum.no/lugm-time.html which I'm surprised hasn't been linked in this thread yet, but was linked on the same topic back in 2011 it seems) and let people sort out how to translate that local time from that reference frame in that particular gravity well. I don't think we want to force users to start embedding their gps coordinates, their current acceleration, etc. along with their timestamp. But it turns out that the unix epoch is only standard at 9.8m/s^2. So ... minutes should be ok right? Joking aside. Clocks run faster on the moon, slower on the ISS, so either clocks are synchronized back to earth seconds, or they use some alternate standard reference time. My expectation is that there will be some time keeping standard that will ensure uniformity and that what we will want to capture is whose seconds they are using to keep track of time, because unix epoch on the moon has a different integer value than on earth, and is likely off by multiple seconds. I guess as long as the moon can participate in earth NTP it will be ok? Otherwise I suspect that the NTP network standard for the celestial body will be what we want to go with/record. I think that will fit in the opening you have created for this in the syntax. So instead of UTC it would be LTC (lunar coordinated time). If you're getting logs from servers on the moon knowing that the system clock was running on LTC and not UTC will be critical. Some future engineer: "Leaving earth was a mistake."