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White House wants Moon to have its own time zone, Coordinated Lunar Time (CLT)
- xenospn 3y ago[flagged]
- linsomniac 3y ago[flagged]
- SketchySeaBeast 3y agoIs "time zone" even the correct term when we're looking at a different frame of reference? "Welcome to Hawaii, each day here is 23.4 hours." I thought the article would be about how the lunar day is 29.5 Terran days.
- philip1209 3y agoIt's a contraction rather than an offset. An interesting question is what the frame of reference for this time is - if the Moon's orbit changes significantly and the contraction factor changes, then this timezone shouldn't be adjusted - almost "de-pegging" it from Earth's time, right?
- ISL 3y agoIt isn't just the speed/shape of the orbit. The gravitational potential difference is a major factor.
- itishappy 3y agoFascinating question! I wonder if GPS satellites use their own special "time zones" too? Apparently so! https://www.ipses.com/eng/in-depth-analysis/standard-of-time-definition/ https://www.ipses.com/eng/in-depth-analysis/standard-of-time...
- onion2k 3y agoThat page is a bit out of date. The last GPS week reset was in April 2019, when it rolled over to 0 again.
- lxgr 3y agoThe GPS week is a calendar issue and not really relevant to this "time zone" (more accurately: time scale?) discussion, though. It's also a non-issue for most applications since it's usually possible to figure out the current year with a precision of at least 9.8 years.
- palmfacehn 3y agoWould it not be simpler for everyone involved to just use UTC?
- sp332 3y agoNo, you would have to calibrate the clocks to run slower to match earth seconds when they are in the moon's weaker gravity. Or constantly sync them to an Earth time source with over two seconds latency.
- queuebert 3y agoNTP has several methods for dealing with large latency that could possibly be adapted.
- masswerk 3y agoBut, using your own frame of reference, you now need to convert to and fro on each cross-access. I don't really see the advantage. Notably, there is no such thing as an ontological second, it's an abstract measurement unit (loosely) bound to the rotation and revolution of the Earth. Moreover, there is no provision for such a cross-reference of basic progression of time in any Date/Time system currently available. Wouldn't be adding a constant coefficient easier? (Notably, we have modified basic constants several times, already.)
- Jeff_Brown 3y agoThat was my thought. Who cares what time it feels like on the moon, if the people making plans and decisions about it are at, say, Cape Canaveral? Once we get humans on the moon, they'll probably want their own time zones -- but in that case this solution still won't be enough, because they'll probably want the time to depend on their lunar longitude, just like it does on Earth.
- baq 3y agoWhat an amazing problem to have, both as a bureaucrat somewhere in a dark office and as the whole humanity...!
- spacephysics 3y ago[flagged]
- joncrane 3y agoGreat. Yet another time zone I have to worry about when writing my scripts.
- skeeter2020 3y agomost important: What impact will this have on the timezone picker for my (yet to be widely used) SaaS app?
- qntty 3y agoWith daylight savings time too, I would hope
- danesparza 3y ago:-/
- junon 3y agoIf memory serves DST is mostly a historical thing for farming and other daylight-centric work due to the Earth's rotational tilt in relation to the sun, right? Unless we have farmers on the moon where this is a consideration I would hope not, given that it's a source of confusion and complexity in timekeeping software.
- aftbit 3y agoFarming? Where does this myth come from? Farmers hate DST. The cows want to be milked according to the sun, not to a clock. https://agamerica.com/blog/myth-vs-fact-daylight-saving-time-farming/ https://agamerica.com/blog/myth-vs-fact-daylight-saving-time...
- engineer_22 3y agoFrom https://en.wikipedia.org/wiki/Daylight_saving_time https://en.wikipedia.org/wiki/Daylight_saving_time : >It is a common myth in the United States that DST was first implemented for the benefit of farmers.[38][39][40] In reality, farmers have been one of the strongest lobbying groups against DST since it was first implemented.[38][39][40] The factors that influence farming schedules, such as morning dew and dairy cattle's readiness to be milked, are ultimately dictated by the sun, so the clock change introduces unnecessary challenges.[38][40][41] >DST was first implemented in the US with the Standard Time Act of 1918, a wartime measure for seven months during World War I in the interest of adding more daylight hours to conserve energy resources.[42][41] Year-round DST, or "War Time", was implemented again during World War II.[42] After the war, local jurisdictions were free to choose if and when to observe DST until the Uniform Time Act which standardized DST in 1966.[42][43] Permanent daylight saving time was enacted for the winter of 1974, but there were complaints of children going to school in the dark and working people commuting and starting their work day in pitch darkness during the winter, and it was repealed a year later.
- SamBam 3y agoOdd to frame it as the "White House wants..." I know the White House is a metonym for the US government, but it usually refers to something at least slightly in the political wheelhouse, like foreign policy or taxes. Why not just say NASA here?
- dragonwriter 3y agoIts literally a directive from the White House Office of Science and Technology Policy; White House is not being used in a figurative sense for “the US government broadly” (which , incidentally, I’ve never seen any major Western media do; Washington, sure, but not the White House) but in a literal, institutional sense. https://www.whitehouse.gov/ostp/news-updates/2024/04/02/white-house-office-of-science-and-technology-policy-releases-celestial-time-standardization-policy/ https://www.whitehouse.gov/ostp/news-updates/2024/04/02/whit...
- SamBam 3y agoAh, fair enough, that wasn't anywhere in the article.
- tekla 3y agoIts literally the first line
- SamBam 3y agoIt absolutely isn't the first line that it's a directive from the White House Office of Science and Technology Policy. It just says "The White House wants..." Again, "The White House" is often a metonym for the US government. [1] I'm not sure why it didn't bother mentioning the Office of Science and Technology Policy. If I had realized that's where it came from, instead of from NASA, I wouldn't have mentioned it. 1. "Metonymy is a figure of speech where the name for one object or concept is substituted for another, related one (as in the White House for the US Government)" https://www.dictionary.com/compare-words/metonymy-vs-synecdoche https://www.dictionary.com/compare-words/metonymy-vs-synecdo...
- WillAdams 3y agoThis was actually discussed in Heinlein's _The Moon is a Harsh Mistress_ --- and dismissed as idiocy, since being in synch with earth for communications was more important, and anyone who needed to would check a table to determine if it was lunar day or night on the surface.
- oaththrowaway 3y agoI loved that book
- queuebert 3y agoWhatever time standard we settle on will need to be re-synchronized periodically, since, according to general relativity, time measured in Earth's gravity well will be running slightly slower than clocks on the moon with its lower gravity. GPS satellites already correct for this.
- queuebert 3y agoNo, I did not RTFA. Hangs head in shame. As an American, I did not expect my government to talk about relativity in a press release.
- yellow_lead 3y agoFuture bug report: App fails to run with clock set to Coordinated Lunar Time
- hackeraccount 3y agoNever wanted a bug reported so bad.
- willvarfar 3y agoThe U in UTC stands for Universal. If we can't use UTC for whole universe, or even for the nearby solar system, should we rename it Coordinated Global or Earth Time (GTC or ETC) instead?
- greggsy 3y agoGTC is easily confused with Galactic Time, which will likely cause mass havoc a rewrites in dead languages like Imperial C and Scala sometime after the year 48,000AD.
- kijin 3y agoA true visionary must plan for job security for millennia to come. Next on the todo list: code up a Kwisatz Haderach to do your all your data modeling work while you slack off. On a more serious note, Galactic Time probably won't be useful because relativity introduces too much irreconcilable error at that scale. We'll be back in the early days of the railroad when every station had their own clock, adjusted to local noon.
- randomdata 3y agoNot to mention that universal, by definition, refers to earth already. Universal does not relate to universe any more than carpet relates to car.
- zokier 3y agoTerrestrial Time is a thing: https://en.wikipedia.org/wiki/Terrestrial_Time https://en.wikipedia.org/wiki/Terrestrial_Time > TT is indirectly the basis of UTC, via International Atomic Time (TAI). Nobody is going to bother renaming UTC at this point, misnomer or not. Besides, if they stop adding leap seconds to UTC (as is planned) the whole point of UTC goes away anyways.
- belter 3y agoYou should not because on Earth, where gravity is relatively strong compared to the Moon, time runs slightly slower due to the gravitational time dilation effect. This means that clocks on Earth tick slightly slower compared to identical clocks in a region of weaker gravity, such as on the Moon's surface. So the UTC is from Earth perspective. From rough calculations, the time experienced on the surface of the Moon is 0.99999999999848 times the experienced on Earth
- gglitch 3y agoAt some point will ISO-8601 have to be updated to include a field for difference in speed of time?
- layer8 3y agoThere is no difference in speed of time. Time always passes one second per second.
- achates 3y agoNot true, on Fridays after lunch time can sometimes pass as slowly as 3 seconds per second.
- aurizon 3y agoI know some bores so good that 100 seconds passes, and I shake my watch ~ 1 second has passed, so there is a subjective localised field around some people..
- seanhunter 3y agoI've been in some 15min standups but actually take 30mins wallclock time, during which interval years pass.
- c54 3y agoTo a local observer yes, but to someone moving at a different speed no! FloatHeadPhysics does a good job explaining some of this https://youtu.be/OpOER8Eec2A https://youtu.be/OpOER8Eec2A
- layer8 3y agoNo, time still passes at one second per second for any observer.
- lxgr 3y agoOnly if you disregard observers in different frames of reference interacting with each other, which you shouldn't when you need high precision and it comes to projects spanning Earth, Earth orbit, and the Moon. GPS wouldn't work without accounting for relativity, for example.
- elzbardico 3y agoWouldn't be easier to just calibrate the clocks and use UTC?
- rob74 3y agoMy thought exactly - the fact that time runs slightly faster on the Moon than on Earth is fascinating, but the pragmatic approach would be to just compensate for the deviation.
- lxgr 3y agoHow would you? Periodic leap seconds, or redefine the second (which would have impacts on many other units of measurements derived from it – are you prepared to also introduce lunar meters, for example)?
- rob74 3y agoThe compensation for the relativistic effects just makes sure that the second on the Moon is the same as the second on Earth. According to the article another commenter linked (https://www.ipses.com/eng/in-depth-analysis/standard-of-time-definition/ https://www.ipses.com/eng/in-depth-analysis/standard-of-time...) this is already routinely done on GPS satellites: > the only corrections made on atomic clocks located on satellites are very small adjustments to ensure that they remain perfectly synchronized with atomic clocks installed on the Earth (usually to correct drifts due to relativistic effects). this takes care of the effect mentioned in the article. However the more relevant (and debatable) question is if "Moon time" should also observe the leap seconds (which are introduced to account for variations in Earth's rotation, so have nothing to do with the Moon).
- lxgr 3y agoThis only works on the GPS satellites because they provide the GPS time for Earth's benefit, not their own. For all internal operations requiring high precision, they'd actually have to keep their own time reference (or calculate a dynamic offset from "GPS time") or they'd get unexpected results since the atomic clocks they carry run fast with regards to the SI definition of a second. (It could be the other way around, i.e. the clocks running correctly with regards to the satellite's frame of reference and an offset being applied to the signal, but I suspect skewing clocks to fit the Earth-based frame is easier.)
- throw0101b 3y agoSomewhat related: * https://en.wikipedia.org/wiki/Timekeeping_on_Mars https://en.wikipedia.org/wiki/Timekeeping_on_Mars
- dotnet00 3y agoJust another symbolic gesture from the White House to try to pretend that they're actually serious about achieving Artemis' goals as they continue to cut NASA's budget while raising the allocation to the waste of material that is SLS, doing nothing more than accomplishing their goal of killing science programs and purchasing votes and future 'advisor' roles at Boing.
- danesparza 3y agoI'm OK with this. Just remove daylight savings shifts here on Earth.
- pseingatl 3y agoSame for Mars, called a "sol." See, marslegalcode.org.
- DrFalkyn 3y agoCoordinate Lunar International Time or CLI-
- bradley13 3y agoWhy? Just use UTC, there is zero reason for anything else. ETA: There is a minor relativistic issue due to the reduced gravity. If the figures I found online are correct, we are talking about 0.02 seconds per year. Surely such a small difference can just be "smeared" away periodically?
- alexdns 3y agoTime dilation - the moon time runs at different pace due to gravity
- thfuran 3y ago0.02 seconds per year is about 55,000 nanoseconds per day, which is kind of a big deal as far as the high precision CPU timers are concerned.
- AdamH12113 3y agoI'm not sure about the larger issues surrounding the lunar time standard, but 55 microseconds per day is about 0.64 ppb. Even good OCXOs drift more than that. A standard crystal oscillator like the kind used in computers drifts by multiple seconds per day. Unless your oscillator costs more than your computer, that kind of accuracy is going to be beneath the noise floor.
- thfuran 3y agoYou're right that CPUs probably weren't the best example. My point was more that there are everyday things that operate at timescales where nanoseconds matter. 55 us per day is larger than the effects of either special or general relativity on GPS, but both need to be accounted for in order for the system to be useful.
- MeImCounting 3y agoThe issues arent arising from cellphones and personal computers. Precise time may not be necessary for building web services but it is the basis of precise navigation systems and other scientific endeavors such as astronomy and quantum computing. Since navigation and science will probably be way up on the todo list above twitter I think nanosecond accuracy lunar time is clearly justified.
- faitswulff 3y ago> But Nasa is not the only one trying to make lunar time a reality. The European Space Agency has also been developing a new time system for a while. Great, lunar time hasn’t even been established and we already have two time zones.
- kayge 3y agoJust wait until one of them pushes for Moonlight Savings Time...
- jh00ker 3y ago[flagged]
- ajaimk 3y agoLet's get rid of DST first; then we can talk about moon time...
- deleted 3y ago[deleted]
- beanjuiceII 3y agoCoordinated Lunar International Time ackshulally
- NovemberWhiskey 3y agoIs it just me, or is the headline terrible? They don't want the moon to have its own timezone; they want it to have its own time standard. i.e. CLT (which will probably end up being LTC for the same reason that UTC is neither TUC or CUT) replaces UTC for lunar operations and any putative lunar timezones would be offsets from that.
- mywittyname 3y agoI hope this prompts Tom Scott to do a follow up on his brilliant video on the complexities of timezone.
- ordu 3y ago> Because of the different gravitational field strength on the Moon, time moves quicker there relative to Earth - 58.7 microseconds every day. So it is beneficial to move computers there because they would make more computation per year. Though 58.7us/day is ~21ms/year which is 6.8e-10, one needs a really big scale to make it meaningful.
- icapybara 3y agoDownloading the result of your multi-year computation would take a long time too, so that needs to be factored in.
- KboPAacDA3 3y agoThe key reason is the Coordinated part. By letting the Moon handle it's own timekeeping, it reduces the hassle of getting regular updates from Earth clocks. Earth-based atomic clocks will continue to measure its own precise second lengths and take measurements of quasars to get accurate wall-clock time. Moon-based atomic clocks can have their own separate network of atomic clocks and measure the same quasars to get the same wall-clock time.
- jenny91 3y agoDo we have any atomic clocks on the moon at the moment?
- mikeyouse 3y agoLooks like "no" but a few years ago they launched / tested the "deep space atomic clock" which seems like it'll be the basis for future space-based clocks. https://en.wikipedia.org/wiki/Deep_Space_Atomic_Clock https://en.wikipedia.org/wiki/Deep_Space_Atomic_Clock
- zokier 3y agoLN-1 that landed recently might have an atomic clock onboard. But the details are scarce so I'm not completely sure.
- kspacewalk2 3y agoStep 1 of N for Lunar Independence. Free Luna!
- deleted 3y ago[deleted]
- euroderf 3y agoCertainly lunar clocks should feature on the first series of lunar postage stamps.
- ivan_gammel 3y ago
- chias 3y agoThere's a typo in the headline here on HN: the initialism for Coordinated Lunar Time is LCT, not CLT. (this isn't my opinion on whether we'll end up following suit with UTC and so on, the article itself calls it "LCT", and "CLT" does not appear on the page at all)
- fullstop 3y agoYes, I searched for the CLT but could not find it.
- j-j-j-j 3y agoThat would be a big improvement in the remote work economy.
- timetraveller26 3y agoOh great, hopefully I will be retired before I have to worry about inter planetary timezone on my django app.
- mikhailfranco 3y agoDoes the IRS claim jurisdiction on the Moon or Mars? (asking for an American friend) Elon - renounce citizenship before blast-off!
- CuriousCosmic 3y agoIn all seriousness, it'd be the same as with antarctic stations where which station you are at determines the rules.
- jgtor 3y agoCan't wait for a 2026 manned moon mission. Get to watch a live moon landing like my grandparents generation!
- idlewords 3y agoNo one is landing on the moon in 2026. SpaceX is two years behind schedule building the lander, and there's not enough room in the calendar to develop and then operationalize the necessary refueling technology. The earliest feasible landing date is probably in 2028.
- withinboredom 3y ago> is two years behind schedule building the ladder I initially read it as that, and didn't even blink. Elon's promises are so ridiculous and inept that being two years behind on building a ladder seems entirely plausible.
- tgsovlerkhgsel 3y ago> over 50 years they would be running one second faster. That's even less than leap seconds on earth, so for practical purposes, I suspect the two will be kept in sync somehow.
- saghm 3y agoGiven that "UTC" means "coordinated universal time" due to a compromise (https://en.wikipedia.org/wiki/Coordinated_Universal_Time#Etymology https://en.wikipedia.org/wiki/Coordinated_Universal_Time#Ety...), would this end up being "LTC" rather than "CLT"?
- lainga 3y agoWhen the French get someone up there, we can consider it.
- pulvinar 3y agoI can see NIST setting up station WWVM: "At the tone, 693 hours, 21 minutes, Coordinated Lunar Time."
- breakingrules 3y ago[dead]
- breakingrules 3y ago[dead]
- gumby 3y agoSo UTC ("Coordinated Universal Time") isn't in fact universal after all? Not even solar-system wide much less galactic. Some marketing department must have been involved.
- benced 3y agoSo what would the prefix for the IANA code be? Right now, it's continent (Asia/Kolkata, America/Chicago etc). Would it just be "Space/Moon"? One can imagine the standard would have to be revised many many times if humans became interplanetary.
- joering2 3y agoSolar_System/The_Moon
- simcop2387 3y agoI'd suggest Sol/Luna or Sol/Terra/Luna, that way it's easier to do Sol/Jupiter/Europa
- ivan_gammel 3y agoIf we will standardize time on solar system level, we’ll probably have another component of time, rather than a flat list of time zones. E.g. Mars should have its own set of zones. Maybe that means having an identifier of coordinate system, which can be omitted in local use cases.
- akira2501 3y ago> So what would the prefix for the IANA code be? I would prefer if IANA/Eggert were not involved on this one. They've already made an absolute mess of the Earth based timezone database. > Would it just be "Space/Moon"? More problematically, how would you define it's coordinates and country code, which are fields in the tzdb for each timezone?
- anticensor 3y agoEarth/Satellites/Moon/Nearside and Earth/Satellites/Moon/Farside preferrably
- fullstop 3y agoThey need to run this stuff past a panel of 14 year old boys.
- daviddever23box 3y agoMight be an excellent opportunity to re-think how we handle timekeeping in general, especially as Local Solar Time will vary wildly by dint of the moon's orbital patterns.
- swader999 3y agoThe article title cracks me up. As if anyone in the Whitehouse even thinks about this. Why don't they just say NASA.
- yencabulator 3y ago> Locating and directing this mission requires extreme precision down to the nanosecond, errors in navigation which could risk spacecraft entering the wrong orbits. I don't see how time on the lunar surface helps with that any more than time on Earth surface does...
- OhNoNotAgain_99 3y ago[dead]
- MasterYoda 3y agoFun fact!? TIL: UTC = Coordinated Universal Time but the abbreviation is not CUT that would be "logical", but UTC. "It came about as a compromise between English and French speakers. - Coordinated Universal Time in English would normally be abbreviated CUT. - Temps Universel Coordonné in French would normally be abbreviated TUC. The International Telecommunication Union (ITU) and the International Astronomical Union wished to minimize confusion and designated one single abbreviation for use in all languages. UTC does not favor any particular language. In addition, the advantage of choosing UTC is that it is consistent with the abbreviation for Universal Time, UT" So the reason it's called UTC is because the French and British couldn't agree, who could have guessed? :)
- tmaly 3y agoI hope they don't plan on a Moon Light Savings time.
- diebeforei485 3y agoIs this dominated by gravitation or relative motion?
- ktosobcy 3y agolet's just adopt stardates ;-)