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White House directs NASA to create time standard for the moon
- docdeek 3y agoHaving just gone through the daylight savings change here in Europe, I found this really fascinating: how __do__ you set up time for the moon where time, at least as we understand it, doesn't really exist? I'm sure that, starting from scratch on Earth, we'd probably come up with a system of time zones that is broadly similar to what we have today but with some new zones and some adapted zones. Then again, maybe we'd find a way to change things up altogether - is there any value to GMT being based on Greenwich if the UK is not the global power it once was?
- euroderf 3y agoWould time zones even be necessary on the Moon ? Sunrise and sunset occur on a scale of Earth days, not Earth hours.
- jfengel 3y agoNope, no time zones. Just one time zone that is "the moon". But somebody somewhere needs to make a standard for that, and this is it.
- euroderf 3y agoStill tho, how about a prime meridian centered on where Neil Armstrong first set foot ?
- jfengel 3y agoThey don't need any meridians. The entire place will be one zone. The time will be the same everywhere. The problem is that the time there will move very slightly differently than here on earth, because of the lower gravity, to the tune of 60 ms per day. That's almost a second every two weeks. So the question isn't "what time do we set the clocks to?" but "what time will it be an hour from now?" Have a leap-second every few weeks?
- psd1 3y agoGMT is a time zone used in Britain. It is no more special than any other. The standard is UTC. If engineers were in charge, there would be no time zones. Brits would get up at 08:00, Indians at 04:00, and Americans at 12:00/13:00/14:00 depending on location. Shops would set their opening hours relative to local sunrise. It's already the case that work-shifts span calendar days for many people, and that franchise locations have differing hours of business, and that fuckwits telephone you when you're trying to sleep.
- srveale 3y agoPeople's eyes glaze over when I rant about this. But yes, I fantasize about a world where you could say "let's set up a video call at 6" and there's no mental math when there's geographic distance involved. Biggest downside I can think of, apart from the entire population groaning about making the switch, would be the confusion from reading literature from the before times. Oh, and all blood, sweat, and tears of all the devs who created timezone code going down the drain.
- t0mas88 3y agoSome industries do this using UTC. For example flight departure and arrival times are in UTC on all paperwork. And also the meteo reports and forecasts, and airspace restrictions, and airport opening times etc. Mostly out of a necessity that fights tend to cross timezones and planes come and go from all over the world and they don't want to have to figure out everywhere what the local time is. Really only passenger info screens convert to local time.
- psd1 3y agoThe biggest downside would be the date rolling over during a record-keeping period. But this is already a problem and people handle it just fine. I mean, we say "tonight" for 02:30 on the following day, so meh.
- rightbyte 3y agoNo no no. We can't make the world adjust to our crappy code. 24:00 is "mid night". 02:30 is not less 'tonight' than 21:30, assuming no DST.
- autoexec 3y agoIf they're going to bother creating a time measurement system for the moon they might as well just invent the Stardate already and use that for everything we do in space from now on regardless of where we are.
- thecosmicfrog 3y agoTime to add a `--stardate` flag to the `date` command then?
- evanb 3y agoMaybe just --star
- JumpCrisscross 3y ago> might as well just invent the Stardate already and use that for everything we do in space from now on regardless of where we are Until we have FTL, that isn't physically possible. If we do, GMT comes with backwards compatibility.
- rkeene2 3y agoTcl is once again ahead of the curve with a stardate format option (%Q)
- euroderf 3y ago> Coordinated Lunar Time (LTC) Ah yes. It appears that the French have already seized control of the appellation process. Except that French media are reporting it as "le temps lunaire coordonné" (TLC?). So the White House seems to be (somewhat blindly?) reproducing the oddity of how "UTC" (with the letters in that order) isn't quite "Universal Coordinated Time".
- euroderf 3y agoAccuracy counts. "... a moon-centric time reference system that accounts for its differing gravitational forces. In a memo on Tuesday, OSTP chief Arati Prabhakar noted that Earth-based clocks would appear to lose 58.7 microseconds per Earth-day as a result of these factors."
- barryrandall 3y agoIt's probably time to start the Falsehoods Programmers Believe About Lunar Time article.
- TrueDuality 3y ago> ... that accounts for its differing gravitational forces ... I salute maintainers of timezone libraries. This is going to be a fun one. You are now responsible for space and time.
- Qqqwxs 3y agoThis comment made me curious. Apparently, TAI specifically defines the second (in terms of cesium transitions) at sea level (where gravitational potential is equal). I never knew that second part.
- Xorathena 3y ago...and one level of language-precision further, these articles get into how "sea level" differs from "where gravitational potential is equal": https://en.wikipedia.org/wiki/Ocean_surface_topography https://en.wikipedia.org/wiki/Ocean_surface_topography https://en.wikipedia.org/wiki/Geoid https://en.wikipedia.org/wiki/Geoid
- torstenvl 3y agoI just know this is going to take weeks or months of planning meetings, stakeholder sensing sessions, and arguments over minutiae. Not a good use of official time and taxpayer resources. It's all arbitrary anyway. Just pick something that makes sense. UTC, UTC+1 (ESA), UTC-6 (Houston), whatever.
- t0mas88 3y agoIt's not about a "timezone", the article is about high precision time keeping and how to set a standard for it on the moon. Because (according to the article) an earth clock when moved to the moon wold be a few micro seconds per day slower then it was on earth, causing drift. So just setting UTC or UTC+1 isn't the ting they're trying to decide. It's more about a scientific method to derive highly accurate time on the moon, which can't just be earth type atomic clocks because they would drift.
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- eek2121 3y agoWouldn't the solution be to use microseconds? Maybe I'm just being naive, I love science, but as I get older it gets hard to keep all the whims of tech in my head.
- lsllc 3y agoSee discussion on BBC version of this story here: https://news.ycombinator.com/item?id=39916102 https://news.ycombinator.com/item?id=39916102
- speedylight 3y agoWatch them try to integrate it into earths time and calendar system somehow
- averageRoyalty 3y ago"U.S. leadership in defining a suitable standard - one that achieves the accuracy and resilience required for operating in the challenging lunar environment - will benefit all spacefaring nations," - some American who believes the US should be the authority for this, shockingly. Why would anyone bother following the US standard for lunar time? They can't even work out the metric system.