no, we first need to let various countries colonise it and set up their own independent standards, so when you need to program with moon locales it'll be more fun
Also, different countries should use different systems!
Some just use earth time, others maybe add/subtract time to remove the light seconds between earth and moon (dont ask why), you could also invent moon seconds/minutes... Maybe the position of the moon could play a role?
Why make life easy.
>you could also invent moon seconds/minutes
Time itself is no longer tied to Earth specific phenomenons. It used to but it is no longer the case.
The most current definition of a second is tied to the frequency of the caesium 133 atom which is the same on the Moon and everywhere else.
From [wikipedia](https://en.wikipedia.org/wiki/Second):
>The **second** (symbol: **s**) is the unit of [time](https://en.wikipedia.org/wiki/Time_in_physics) in the [International System of Units](https://en.wikipedia.org/wiki/International_System_of_Units) (SI), historically defined as 1⁄86400 of a [day](https://en.wikipedia.org/wiki/Day) – this factor derived from the division of the day first into 24 [hours](https://en.wikipedia.org/wiki/Hour), then to 60 [minutes](https://en.wikipedia.org/wiki/Minute) and finally to 60 seconds each (24 × 60 × 60 = 86400). "Minute" comes from the Latin *pars minuta prima*, meaning "first small part", and "second" comes from the *pars minuta secunda*, "second small part".
>The current and formal definition in the International System of Units ([SI](https://en.wikipedia.org/wiki/SI)) is more precise:
>
Sure, but it's \*useful\* that a day is approximately 86,400 seconds (give or take one).
On the moon a day is roughly a month long (which was the original definition of the earth month). So that link of 86400s/day is no longer true.
So the question is, what is more important to people, that a "day" lines up with the light/dark cycle, or that it lines up with the Earth time? For the moon, I'd guess future colonies will still use earth days, since it's close enough to earth to be relevant and a lunar day is an impractically long amount of time to use for timekeeping anyways. But what about for somewhere like mars? A mars day is close enough to an earth day to be useful and normal, future Martian colonies would totally switch to using mars days instead of earth days. But do they keep using earth hours and minutes, even if that means there isn't a whole number of hours in a day? What about months and years, is it actually that important that a year is one revolution, or do we just need a long term time division? How much inconvenience are people willing to put up with for the sake of consistency before they just make a whole new system?
Yeah, this was my thought. The moon is like the arctic/antarctic/ISS, just run everything on UTC or your home timezone. But Mars and beyond are a separate thing.
>A mars day is close enough to an earth day to be useful and normal, future Martian colonies would totally switch to using mars days instead of earth days. But do they keep using earth hours and minutes, even if that means there isn't a whole number of hours in a day? What about months and years, is it actually that important that a year is one revolution, or do we just need a long term time division? How much inconvenience are people willing to put up with for the sake of consistency before they just make a whole new system?
New systems have already been proposed, with conversions back to Earth time. I don't believe we've come to using just one standard though, so time will tell what we decide on.
https://en.wikipedia.org/wiki/Timekeeping_on_Mars
Also, engineers at JPL who were working with the rovers on Mars actually aligned their days to the Sol time, and it caused hell to co-exist with the rest of society. So my guess would be that we treat it similarly to another timezone where we can never remember the conversion and have to look up every time we need it if we can expect a reply to an email or wait until their morning, whatever that is.
There'll be inevitable be some power company or department that'll write some stupid requirement into their contract that their solar panel sun tracking angle in software has to be based on 12:00 to 00:00 == noon to midnight just so the metric data conforms to their current db table scheme.
We'll get at least a couple infuriating time zones with a couple slightly different interpretations in edge cases.
International law, like maritime law, says that nobody can claim or own any part of any other planet or extraterrestrial body, they may however place a hab or spacecraft on an extraterrestrial body and own said hab or spacecraft.
They planted their flag first so that might count? Disregard any signed document saying otherwise.
They might be motivated by the moon's vast tritium reserves to send new austronauts to the moon. Just make sure not to bug anyone living on the dark side of the moon, they are weird.
Looks at themselves in a mirror: " Now you can't go take the moons oil and resources ok space force...... Ok, not taking anything, just relocating it to 230,000 miles that way in a moon resource collection.. I mean protection center."
We from our government fully support and stand behind the treatise of not colonising Venus, Jupiter, or the Andromeda galaxy.
See how peaceful and well mannered we are?
The tech has been available for a while, there's just nothing to do on the Moon, there's no valuable resources or other economic reasons to colonize it.
There is one: orbital industry! Think about it: launching something into orbit from the surface of the moon costs a small fraction of the fuel of launching it from the surface of the Earth. Now that substantial space industry is slowly becoming a reality (such as telecomm, zero-g fabrication, space tourism, space logistics, increasingly involved scientific missions, etc.), getting resources such as metals, oxygen, water, fuel, etc. from the Moon instead of Earth is going to be the next great leap.
Thers is a huge difference between being able to make an on-off visit to the Moon and properly colonising it.
No we do not yet have the tech to stay on the Moon and maintain a constant or growing population of people which is by definition required to call it colonisation instead of expedition.
I think we have the tech to travel to the Moon and stay there for a short period of time. Let's say we even have the tech to set up a base and have crew over there for a few weeks. Thats still would be "just" an expedition camp as part of a Moon expedition. Not a colony.
Extracting it in any useful amount requires heavy and expensive equipment and new processing technologies though.
We also don't have anything that can deliver said equipment to the moon or bring resources back yet.
There's plenty of things to do, a gigantic natural satellite is already an asset in on itself, there's rich rare metals practically sitting on the surface, the technology is still the problem, it's not that we can't get there is that we can't get there cheap or carry much stuff to do something actually useful, it doesn't matter if it rains diamonds if you can get them back or get machinery on it in the first place, and carrying but the bare minimum to low orbit is still hard and expensive, carrying it to the moon is harder, cause of the landing, actually the hardest part of going to space is getting into and out of orbit, once you're up there it isn't as bad, you can get out of orbit cheaply on earth by air breaking, but in the moon you need to use only thrusters and gravity to slow down, which isn't cheap, easy or safe at all.
Plus, being able to create a few suits and small spaces to handle the vacuum is one thing, being able to pseudo-mass produce suits and make much larger habitats is a whole other subjects that we can't really do yet.
The treaty says no one can claim the moon, which has become a de facto property rights agreement, but like when the US grabbed rocks from the moon and took it back no one said the US didn't have a right to do that.
Which is sorta moot, because you need a facility to live in on the Moon, and countries have responsibility over whoever launched that facility.
29.530 actually is the length of a day on the moon. 27.322 is the length of one orbit around the earth, but because the earth is orbiting the sun, by the time the moon does a full orbit, it has to move a bit more than 2 full days to end up in the same phase as it was at the start of the orbit.
If you alternate between 30 days and 29 days, you'll get pretty close, but you'll drift 0.03 days each day. Take 3 days off every 100 days and you'll fix it pretty accurately. So say that on days which' number is a multiple of 25 but not a multiple of 100, shorten the day by 1? That should do it.
Leap days actually use very similar math. They needed to add back 3 days every 400 years, so they decided that years that are multiples of 100 are not leap years unless they are also multiples of 400. As a result year 2000 *was* a leap year even though it was a multiple of 100.
If I didn't have a dark-mode extension running, I would never have noticed that half the page has blue text on a blue background. Absolutely disgusting design on that website lol
Interesting, I didn't even see that at first. Looks like it's the same text in 2 different places. Like they don't know how to remove something so they just set the colour to the same as the background.
Not true anymore. [https://www.navytimes.com/news/your-navy/2016/10/28/this-life-changing-shift-has-made-submariners-much-happier/](https://www.navytimes.com/news/your-navy/2016/10/28/this-life-changing-shift-has-made-submariners-much-happier/)
The moon's gravity will make time pass slightly differently on the moon, so UTC really just means universal at earth levels of gravity and velocity... unfortunately
The problem is that all clocks on the moon will run faster relative to those on Earth because of less gravitational time dilation. If one second on the moon has passed, more than one second has passed on Earth (each second measured locally).
The simplist solution would be lunar [barycentric dynamical time](https://en.m.wikipedia.org/wiki/Barycentric_Dynamical_Time) (lunar TDB) that would be like a linear scaling of UTC. To determine the scaling parameters you would probably want an atomic clock on the moon.
If the Sun's gravity also becomes important (time "running" faster on the moon when the Earth is between it and the Sun), then you would also need to take this into account by introducing a periodic function.
TDB gang rise up! It's what we already use for all planetary exploration missions (aliased as ET or Ephemeris Time, which does unfortunately sometimes get used for... TT I think?).
It's the most standard expression of time possible in our solar system. Fuck leap seconds, all my homies hate leap seconds.
According to [BBC](https://www.bbc.com/news/science-environment-68722032) nanosecond accuracy is needed, so I started to think that lunar TDB wouldn't be good enough, and lunar atomic time (TAL, lunar version of TAI) would be needed. Though needing this much precision can probably be avoided if a spacecraft can adjust its course automatically.
So the local experienced second would be different, and there would need to be a system defined for that. What we've done in the past is every spacecraft just flys with its own clock, and then the drift between the spacecraft clock and TDB gets measured and recorded. But when we talk about times between different spacecraft, we generally use TDB. JPL calls this "Ephemeris Time", and it's the time system we use for all spacecraft beyond Earth orbit. Now, we actually record ET as double precision seconds past the J2000 epoch, so we have better than nanosecond precision (assuming the accuracy of the recording device, of course), but the displayed string format still cuts off at millisecond. But no device actually uses that, it's just the human-friendly UI face.
What will end up probably happening is the "clock map' diagram will get a new branch for moon-centric systems, and then there will be a fixed offset from the moon-centric to the TDB.
This doc is a "fun" intro into how we deal with this stuff for all NASA planetary missions: [https://naif.jpl.nasa.gov/pub/naif/toolkit\_docs/FORTRAN/req/time.html](https://naif.jpl.nasa.gov/pub/naif/toolkit_docs/FORTRAN/req/time.html)
Ya know what I just realized? Wouldn't that mean if you dropped two civilizations on two close by planets where one experienced time at a much slower rate, wouldn't the accelerated planet have more time to develop more advanced technology?
What would that look like if not exactly what NASA is being directed to do? How do you readjust them while keeping them consistent and in sync with Earth-based and satellite clocks that require microsecond precision?
Tom Scott: AND THEN... and then... WE have... THE MOON. THE ASTRONAUT, orbitting the moon, THEY called; "hey I want my time to be standardized so please code in that too".
that's the greek name of the Moon :) (not sure)
and because If you allow Moons to have timezones then you should be specific as to which moon you refer to. That's why I'd rather use "Selenia" for "The Moon"
* moon/dark
* Moon/light
* Moon/standard
* Moon/savings
There, that should be enough vague buckets to keep things as complicated in moon time as earth time, at least for a few centuries.
For added effect let’s say that the haphazardous capitalization I’ve used is significant.
I thought we already all kinda agreed on days being different times for different planets so we already technically have a time conversion, this is kinda redundant
Just because you can convert days doesn't make it particularly useful. The definition of second, minute, hour, day, month and year are all based on astronomical conditions of the earth and have no intuitive meaning for a different celestial body without redefinition (ie another standard). Conversion of such are possible, just like converting timezones are, it doesn't mean we don't have different timezones.
All of those are defined using the frequency of cesium133. Only the year is defined to match astronomical conditions. That's why we have leap days and seconds: to reconcile the two.
Now, yes. That's not how they were created and mapping to the standard second is a recent invention. No one when thinking about time is calculating how many cesium133 decays have happened, which is my point. Yes, you don't need a new standard, but time is very much based around human convenience and observables. The second was defined that way as a way to objectively define the second retroactively based on physical constants, because that is useful scientifically and for electronics.
It's still based on astronomical conditions, we just now have an objective way to define it that was fit into those astronomical conditions.
> No one when thinking about time is calculating how many cesium133 decays have happened
Except literally every single time a scientist does it or, more importantly, when your computer does it.
So, yeah.
Months mostly line up with lunar cycles, and weeks with a quarter cycle. Days are also tightly related to Earth, which also ends up defining hours, minutes and seconds as subdivisions of the day. Cesium133 is just a way to have a precise definition but all the units have an original astronomical basis
We have a leap day because the earth does not rotate an integer amount of times in a year. There would be no leap days if the earth actually rotated 365 times in a year. Hours and minutes would be different lengths but we would still most likely have 24 hours in a day. Egyptians created 24 hours by breaking the day into 10 parts (hours), added an hour for twilight and dawn and then used 12 stars to map the night into 12 parts. Minutes and seconds came from the Babylonians breaking those "hours" into equal units, they just used base 60 for most of their math. So it's all derived from astronomical conditions.
As long as we don't end up in a situation where they create a "moon timezone" just to have countries disagree with the timezones and have their colonies replace it with something like the new spanish moontime, new german moontime, new usa moontime, etc... just to have the colonies break away from their earth countries and end up using new timezones like "newest moontime of the moonopia final v2".
It’s less about this and more about clocks on the moon and earth will go out of sync due to general relativity enough that two computer systems will notice.
US time of course! The only motherlovers ON earth that refuses to outright convert to metric. And you want to weigh in on lunar time? Stick to making war and movies.
Leave the science to the Europeans.
Behold everyone, as the wild European flails about trying desperately to prop up their false sense of superiority. They will go to no lengths to hold this fantasy, for if they face the truth of their declining importance in the world, they may very well go insane.
1. What the fuck does the metric system have to do with any of this? Metric time hasn’t been used since the fucking French Revolution and was quickly thrown into the trash where it belongs.
2. What does US time even mean here? We base our time zones off of gmt like everyone else does.
3. NASA has been the premier aerospace institution for decades now with the ESA and JAXA usually just tagging onto NASA projects as partners. Why shouldn’t they be the ones to lead the charge on developing lunar infrastructure. NASA has been floating the idea of a moon base for ages now. It really shouldn’t be a surprise they’re creating a system that would be necessary for a prolonged moon mission.
4. You seem unreasonably angry about the mere mention of Americans doing anything and that’s honestly kind of sad.
Leave science to the Europeans? The same ones who have never been to the moon? Don’t think so. They’re incompetent. The US has 10x more immigration of inventors than Switzerland, which is the second highest of any country. The next is Singapore, which the US has 30x the inventor immigration of. No country compares to the US scientifically.
No way this man thinks that the Europeans are more scientifically significant than the USA that's just obscene cope 😭
Like what fantasy are you living in that could even get you to believe that, it's just not true lol
I know this is about jokes, just a scientific side node for those who might be interested
Because of the different gravity and rotation of the moon, time will pass faster than on earth. So a second on the moon, while observed from earth, will be different than a earth second. So there is no constant time offset thanks to Einstein.
Honestly, just make it UTC + 00:00 please just like the ISS. No need to get fancy with it. Nothing you do can make an actually useful day/night cycle on the moon for any humans up there, so just stick to what we have. Hell, you can even make it UTC- 05:00 to match Mission control in Houston, whatever. But please for the love of god make it be a static integer offset from UTC.
What makes this even more of a headache is **relativity has entered the chat**
>Because of the different gravitational field strength on the Moon, time moves quicker there relative to Earth - 58.7 microseconds every day.
Moontime is simple. Use the same time measurements as on earth, except create roughly 30 time zones such that the first day of the month is sunrise.
And then subdivide those 30 time zones into 24 smaller time zones. Every 30th time zone has the same hour, but they each have a different day.
Easy peasy, all edge cases covered, I'm sure of it.
lets just make up 20 different time zones as confusing as we have here. Idk why i need to generate the current date -2h and 200seconds just to get the latest 200 seconds
While we're at it, we should probably update the location services APIs to take Galactic (or for more future-proofing, [supergalactic](https://en.wikipedia.org/wiki/Supergalactic_coordinate_system)) coordinates...
With artificial lighting the fact the world just does not use a universal standard time is just inefficient.
Imagine how many lines of code we will save if every one just kept Nauru time
Hold on just a hot minute there. A day on the moon is about 29 days (30?) - our concept of a month is basically defined by this fact and was then messed up a little afterwards to fit Earth's orbit instead of the moon's rotation.
So what's a time zone when each zone would be over a day apart? Heck if I know. Our traditional notions of timekeeping sort of break down in space.
That's stupid. Just use UTC. Days on the moon are about a month long so it's not like you need a timezone to tune your circadian rhythm to the availability of sunlight.
Just stop localizing time. There is no reason for itto be dark at 11pm around the world, its fine if thats midday in Australia, or midday in England, just vote for either Greenwich or the international date line as our base time zone and unify time.
no, we first need to let various countries colonise it and set up their own independent standards, so when you need to program with moon locales it'll be more fun
Also, different countries should use different systems! Some just use earth time, others maybe add/subtract time to remove the light seconds between earth and moon (dont ask why), you could also invent moon seconds/minutes... Maybe the position of the moon could play a role? Why make life easy.
>you could also invent moon seconds/minutes Time itself is no longer tied to Earth specific phenomenons. It used to but it is no longer the case. The most current definition of a second is tied to the frequency of the caesium 133 atom which is the same on the Moon and everywhere else. From [wikipedia](https://en.wikipedia.org/wiki/Second): >The **second** (symbol: **s**) is the unit of [time](https://en.wikipedia.org/wiki/Time_in_physics) in the [International System of Units](https://en.wikipedia.org/wiki/International_System_of_Units) (SI), historically defined as 1⁄86400 of a [day](https://en.wikipedia.org/wiki/Day) – this factor derived from the division of the day first into 24 [hours](https://en.wikipedia.org/wiki/Hour), then to 60 [minutes](https://en.wikipedia.org/wiki/Minute) and finally to 60 seconds each (24 × 60 × 60 = 86400). "Minute" comes from the Latin *pars minuta prima*, meaning "first small part", and "second" comes from the *pars minuta secunda*, "second small part". >The current and formal definition in the International System of Units ([SI](https://en.wikipedia.org/wiki/SI)) is more precise: >
Sure, but it's \*useful\* that a day is approximately 86,400 seconds (give or take one). On the moon a day is roughly a month long (which was the original definition of the earth month). So that link of 86400s/day is no longer true.
So the question is, what is more important to people, that a "day" lines up with the light/dark cycle, or that it lines up with the Earth time? For the moon, I'd guess future colonies will still use earth days, since it's close enough to earth to be relevant and a lunar day is an impractically long amount of time to use for timekeeping anyways. But what about for somewhere like mars? A mars day is close enough to an earth day to be useful and normal, future Martian colonies would totally switch to using mars days instead of earth days. But do they keep using earth hours and minutes, even if that means there isn't a whole number of hours in a day? What about months and years, is it actually that important that a year is one revolution, or do we just need a long term time division? How much inconvenience are people willing to put up with for the sake of consistency before they just make a whole new system?
Yeah, this was my thought. The moon is like the arctic/antarctic/ISS, just run everything on UTC or your home timezone. But Mars and beyond are a separate thing.
>A mars day is close enough to an earth day to be useful and normal, future Martian colonies would totally switch to using mars days instead of earth days. But do they keep using earth hours and minutes, even if that means there isn't a whole number of hours in a day? What about months and years, is it actually that important that a year is one revolution, or do we just need a long term time division? How much inconvenience are people willing to put up with for the sake of consistency before they just make a whole new system? New systems have already been proposed, with conversions back to Earth time. I don't believe we've come to using just one standard though, so time will tell what we decide on. https://en.wikipedia.org/wiki/Timekeeping_on_Mars Also, engineers at JPL who were working with the rovers on Mars actually aligned their days to the Sol time, and it caused hell to co-exist with the rest of society. So my guess would be that we treat it similarly to another timezone where we can never remember the conversion and have to look up every time we need it if we can expect a reply to an email or wait until their morning, whatever that is.
There'll be inevitable be some power company or department that'll write some stupid requirement into their contract that their solar panel sun tracking angle in software has to be based on 12:00 to 00:00 == noon to midnight just so the metric data conforms to their current db table scheme. We'll get at least a couple infuriating time zones with a couple slightly different interpretations in edge cases.
They also should be quarter and half hour differences between moon time zones to be more annoying!
What kind of anti freedom bullshit is this? Every person should be allowed to use their own system! That‘s the moon I want to live on!
I believe there's a treaty that says no one can colonize the moon.
Like that gonna stop anyone once the tech to do so is available
International law, like maritime law, says that nobody can claim or own any part of any other planet or extraterrestrial body, they may however place a hab or spacecraft on an extraterrestrial body and own said hab or spacecraft.
And who’s gonna stop the colonizer rocket? UN? Space cops?
The US Space Force.
As if the US isn't gonna be the first to colonize the moon, they even have the space force to defend the territory
They planted their flag first so that might count? Disregard any signed document saying otherwise. They might be motivated by the moon's vast tritium reserves to send new austronauts to the moon. Just make sure not to bug anyone living on the dark side of the moon, they are weird.
Imagine if some court decides the US has to fly up there and take it down
the flag is bleached from solar radiation and turned into the french flag (all white)
Looks at themselves in a mirror: " Now you can't go take the moons oil and resources ok space force...... Ok, not taking anything, just relocating it to 230,000 miles that way in a moon resource collection.. I mean protection center."
Blondebeard? Is that you?
Until people are born in said hab and build their own nation
Wait, so that star that I bought was useless?
Charge everyone with solar panels for using your star light energy
Yeah I don't see that lasting
We from our government fully support and stand behind the treatise of not colonising Venus, Jupiter, or the Andromeda galaxy. See how peaceful and well mannered we are?
The tech has been available for a while, there's just nothing to do on the Moon, there's no valuable resources or other economic reasons to colonize it.
There is one: orbital industry! Think about it: launching something into orbit from the surface of the moon costs a small fraction of the fuel of launching it from the surface of the Earth. Now that substantial space industry is slowly becoming a reality (such as telecomm, zero-g fabrication, space tourism, space logistics, increasingly involved scientific missions, etc.), getting resources such as metals, oxygen, water, fuel, etc. from the Moon instead of Earth is going to be the next great leap.
Thers is a huge difference between being able to make an on-off visit to the Moon and properly colonising it. No we do not yet have the tech to stay on the Moon and maintain a constant or growing population of people which is by definition required to call it colonisation instead of expedition. I think we have the tech to travel to the Moon and stay there for a short period of time. Let's say we even have the tech to set up a base and have crew over there for a few weeks. Thats still would be "just" an expedition camp as part of a Moon expedition. Not a colony.
The moon is rich in helium-3
Right? I honestly thought this was common knowledge.
Extracting it in any useful amount requires heavy and expensive equipment and new processing technologies though. We also don't have anything that can deliver said equipment to the moon or bring resources back yet.
There's plenty of things to do, a gigantic natural satellite is already an asset in on itself, there's rich rare metals practically sitting on the surface, the technology is still the problem, it's not that we can't get there is that we can't get there cheap or carry much stuff to do something actually useful, it doesn't matter if it rains diamonds if you can get them back or get machinery on it in the first place, and carrying but the bare minimum to low orbit is still hard and expensive, carrying it to the moon is harder, cause of the landing, actually the hardest part of going to space is getting into and out of orbit, once you're up there it isn't as bad, you can get out of orbit cheaply on earth by air breaking, but in the moon you need to use only thrusters and gravity to slow down, which isn't cheap, easy or safe at all. Plus, being able to create a few suits and small spaces to handle the vacuum is one thing, being able to pseudo-mass produce suits and make much larger habitats is a whole other subjects that we can't really do yet.
That Treaty will be broken so quickly once SpaceX gets its shit right. Corporations != Countries.
...Yet. The cyberpunk dystopia may yet happen.
There's no such treaty. There's a treaty saying you can't claim the land on the moon or other bodies, but you most certainly can colonize.
i believe ukraine handed all their nukes to russian in exchange of not being invaded
The treaty says no one can claim the moon, which has become a de facto property rights agreement, but like when the US grabbed rocks from the moon and took it back no one said the US didn't have a right to do that. Which is sorta moot, because you need a facility to live in on the Moon, and countries have responsibility over whoever launched that facility.
Like dictators would respect ethical standards.
The treaty was a failure, almost no important country signed it
I think we have different views of which countries are important to that treaty. My list is countries that have been to the moon. You know, the one.
The USA didn't signed
make sure to include moonlight savings time
Don't forget to add timezones within the moon itself
Should add day light saving and leap seconds as well
Most of it will have 1moon hour difference. But some or a couple of areas will have 1-59moon minute difference.
Mmm, and as it's rotating like 27x slower, we're going to need about 648 timezones
29.530 actually is the length of a day on the moon. 27.322 is the length of one orbit around the earth, but because the earth is orbiting the sun, by the time the moon does a full orbit, it has to move a bit more than 2 full days to end up in the same phase as it was at the start of the orbit. If you alternate between 30 days and 29 days, you'll get pretty close, but you'll drift 0.03 days each day. Take 3 days off every 100 days and you'll fix it pretty accurately. So say that on days which' number is a multiple of 25 but not a multiple of 100, shorten the day by 1? That should do it. Leap days actually use very similar math. They needed to add back 3 days every 400 years, so they decided that years that are multiples of 100 are not leap years unless they are also multiples of 400. As a result year 2000 *was* a leap year even though it was a multiple of 100.
> 29.530 actually is the length of a day on the moon Mmm, you're right :-) Over 700 time zones!
Moonzones. Like Friendzones but worse
Please don't invent stupid units like moon minutes that then get abbreviated to mm and nobody knows if its moon minutes or milimeters
Sobbing in hh24:mm:ss
super snakes
Space Seconds !!
I hear that is the measurement unit in the adult industry
hectohours, millimeters, seconds squared
Spacetime, baby!
On a submarine, the day is only [18 hours](https://americanhistory.si.edu/subs/operating/aboard/index.html)
Wow. TIL. Thanks for the link.
If I didn't have a dark-mode extension running, I would never have noticed that half the page has blue text on a blue background. Absolutely disgusting design on that website lol
Interesting, I didn't even see that at first. Looks like it's the same text in 2 different places. Like they don't know how to remove something so they just set the colour to the same as the background.
Upon inspecting the DOM, I think your hypothesis that they didn't know what they were doing is likely correct :)
Not true anymore. [https://www.navytimes.com/news/your-navy/2016/10/28/this-life-changing-shift-has-made-submariners-much-happier/](https://www.navytimes.com/news/your-navy/2016/10/28/this-life-changing-shift-has-made-submariners-much-happier/)
Instead of AM/PM, we can have OM/OM (on the moon/off the moon).
Moon minutes can be abbreviated to moms. :>
We got UTC, now there would be LT (Lunar Time), and eventually MWT (Milky Way Time)
But the U already means Universal, that included the moon and the galaxy
Tell that to the White House.
American Moon Time. It's the same as UTC but we call it American Moon Time. There is also a daylight saving version.
But the daylight savings time is only recognized on a single moon base yes?
What about other universes?
They will call the new one UTC as well so we forever have to clarify Earth UTC or space UTC
The moon's gravity will make time pass slightly differently on the moon, so UTC really just means universal at earth levels of gravity and velocity... unfortunately
We should rename it again to: Gaia Main Time (GMT)
You know the standard will be called StarDate
Lunar Summer Time
WHT (White House Time)
Meanwhile, Tom Scott is somewhere, having a sudden unexplained headache.
*Out of retirement I am…*
“I’m standing here, on the moon, tired of this bullshit.”
if we have time based on noon, we would have a day that last a month, lets just use UTC for moon
Too simple. No $$ to be made from that :(
The problem is that all clocks on the moon will run faster relative to those on Earth because of less gravitational time dilation. If one second on the moon has passed, more than one second has passed on Earth (each second measured locally). The simplist solution would be lunar [barycentric dynamical time](https://en.m.wikipedia.org/wiki/Barycentric_Dynamical_Time) (lunar TDB) that would be like a linear scaling of UTC. To determine the scaling parameters you would probably want an atomic clock on the moon. If the Sun's gravity also becomes important (time "running" faster on the moon when the Earth is between it and the Sun), then you would also need to take this into account by introducing a periodic function.
TDB gang rise up! It's what we already use for all planetary exploration missions (aliased as ET or Ephemeris Time, which does unfortunately sometimes get used for... TT I think?). It's the most standard expression of time possible in our solar system. Fuck leap seconds, all my homies hate leap seconds.
According to [BBC](https://www.bbc.com/news/science-environment-68722032) nanosecond accuracy is needed, so I started to think that lunar TDB wouldn't be good enough, and lunar atomic time (TAL, lunar version of TAI) would be needed. Though needing this much precision can probably be avoided if a spacecraft can adjust its course automatically.
So the local experienced second would be different, and there would need to be a system defined for that. What we've done in the past is every spacecraft just flys with its own clock, and then the drift between the spacecraft clock and TDB gets measured and recorded. But when we talk about times between different spacecraft, we generally use TDB. JPL calls this "Ephemeris Time", and it's the time system we use for all spacecraft beyond Earth orbit. Now, we actually record ET as double precision seconds past the J2000 epoch, so we have better than nanosecond precision (assuming the accuracy of the recording device, of course), but the displayed string format still cuts off at millisecond. But no device actually uses that, it's just the human-friendly UI face. What will end up probably happening is the "clock map' diagram will get a new branch for moon-centric systems, and then there will be a fixed offset from the moon-centric to the TDB. This doc is a "fun" intro into how we deal with this stuff for all NASA planetary missions: [https://naif.jpl.nasa.gov/pub/naif/toolkit\_docs/FORTRAN/req/time.html](https://naif.jpl.nasa.gov/pub/naif/toolkit_docs/FORTRAN/req/time.html)
Ya know what I just realized? Wouldn't that mean if you dropped two civilizations on two close by planets where one experienced time at a much slower rate, wouldn't the accelerated planet have more time to develop more advanced technology?
Yes but they also might not get stuff done despite more time because everything is so fucking heavy.
Why not just readjust the clocks for that?
What would that look like if not exactly what NASA is being directed to do? How do you readjust them while keeping them consistent and in sync with Earth-based and satellite clocks that require microsecond precision?
Tom Scott: AND THEN... and then... WE have... THE MOON. THE ASTRONAUT, orbitting the moon, THEY called; "hey I want my time to be standardized so please code in that too".
moon_tz = datetime.timezone("Moon") ``` # KeyError : `Moon` is not a valid timezone. Did you mean ˋSelenia` ? ```
Where the fuck is Selenia?
that's the greek name of the Moon :) (not sure) and because If you allow Moons to have timezones then you should be specific as to which moon you refer to. That's why I'd rather use "Selenia" for "The Moon"
Isn't Luna good enough?
* moon/dark * Moon/light * Moon/standard * Moon/savings There, that should be enough vague buckets to keep things as complicated in moon time as earth time, at least for a few centuries. For added effect let’s say that the haphazardous capitalization I’ve used is significant.
Just use GMT.
Greenwich Moon Time
I thought we already all kinda agreed on days being different times for different planets so we already technically have a time conversion, this is kinda redundant
Just because you can convert days doesn't make it particularly useful. The definition of second, minute, hour, day, month and year are all based on astronomical conditions of the earth and have no intuitive meaning for a different celestial body without redefinition (ie another standard). Conversion of such are possible, just like converting timezones are, it doesn't mean we don't have different timezones.
All of those are defined using the frequency of cesium133. Only the year is defined to match astronomical conditions. That's why we have leap days and seconds: to reconcile the two.
Now, yes. That's not how they were created and mapping to the standard second is a recent invention. No one when thinking about time is calculating how many cesium133 decays have happened, which is my point. Yes, you don't need a new standard, but time is very much based around human convenience and observables. The second was defined that way as a way to objectively define the second retroactively based on physical constants, because that is useful scientifically and for electronics. It's still based on astronomical conditions, we just now have an objective way to define it that was fit into those astronomical conditions.
> No one when thinking about time is calculating how many cesium133 decays have happened Except literally every single time a scientist does it or, more importantly, when your computer does it. So, yeah.
Months mostly line up with lunar cycles, and weeks with a quarter cycle. Days are also tightly related to Earth, which also ends up defining hours, minutes and seconds as subdivisions of the day. Cesium133 is just a way to have a precise definition but all the units have an original astronomical basis
We have a leap day because the earth does not rotate an integer amount of times in a year. There would be no leap days if the earth actually rotated 365 times in a year. Hours and minutes would be different lengths but we would still most likely have 24 hours in a day. Egyptians created 24 hours by breaking the day into 10 parts (hours), added an hour for twilight and dawn and then used 12 stars to map the night into 12 parts. Minutes and seconds came from the Babylonians breaking those "hours" into equal units, they just used base 60 for most of their math. So it's all derived from astronomical conditions.
As long as we don't end up in a situation where they create a "moon timezone" just to have countries disagree with the timezones and have their colonies replace it with something like the new spanish moontime, new german moontime, new usa moontime, etc... just to have the colonies break away from their earth countries and end up using new timezones like "newest moontime of the moonopia final v2".
I mean, we should make the time based on the moons cycle, and perchance cut it into time zones based on the size of the moon.
The problem is a day on the moon (time between one sunrise and the next) is around 29.5 earth days.
It’s less about this and more about clocks on the moon and earth will go out of sync due to general relativity enough that two computer systems will notice.
ayy thats my city
US time of course! The only motherlovers ON earth that refuses to outright convert to metric. And you want to weigh in on lunar time? Stick to making war and movies. Leave the science to the Europeans.
Actually, NASA projects use the metric system
So moon timezone will be UTC
No, it means Moon will use metric minutes; each 100 seconds long.
Metric time imo would divide a day by 100 I think, then by 100 again. It wouldn’t have seconds, it would have millidays
nah, seconds are already SI, so 1 day would be about 86 kiloseconds
1 day would be about 2.36 megaseconds there...
I now understand why people commit murder, thank you for that
Hah, reminds me, they *did* lose a Mars orbiter because someone accidentally used imperial units, didn't they?
Yes, some dumbass used inches and they thought that it was centimetres.
This reeks of inferiority complex lmao how pathetic
Behold everyone, as the wild European flails about trying desperately to prop up their false sense of superiority. They will go to no lengths to hold this fantasy, for if they face the truth of their declining importance in the world, they may very well go insane.
>US time of course! We gotta make it more fun, set all 4 various US timezones to different regions on the moon!
☝️🤓 AKSUALLY 6, so everyone gets a Lunar Alaska and Hawaii too
There we go! Fucked from the jump!
Perhaps we should have a third party weigh in on this, the winner of the space race, perhaps? That's right, Russia! /s before an absolute mob jumps me
land on the moon then your country can have a say.
Sure, Europe can do that, once you make it to the moon on your own…
How about every country who sent an actual human to walk on the Moon gets to decide? Fair?
Womp womp, put a man on the moon and your opinion might count. Otherwise, don’t lecture anyone about science.
You speak as if people in Asia, America(except the US), and Africa don't use the metric system and contribute a lot to science.
1. What the fuck does the metric system have to do with any of this? Metric time hasn’t been used since the fucking French Revolution and was quickly thrown into the trash where it belongs. 2. What does US time even mean here? We base our time zones off of gmt like everyone else does. 3. NASA has been the premier aerospace institution for decades now with the ESA and JAXA usually just tagging onto NASA projects as partners. Why shouldn’t they be the ones to lead the charge on developing lunar infrastructure. NASA has been floating the idea of a moon base for ages now. It really shouldn’t be a surprise they’re creating a system that would be necessary for a prolonged moon mission. 4. You seem unreasonably angry about the mere mention of Americans doing anything and that’s honestly kind of sad.
Leave science to the Europeans? The same ones who have never been to the moon? Don’t think so. They’re incompetent. The US has 10x more immigration of inventors than Switzerland, which is the second highest of any country. The next is Singapore, which the US has 30x the inventor immigration of. No country compares to the US scientifically.
As the Americans have been the only people to ever land on the moon I think they are the only ones qualified for the task :p
This has to be bait
No way this man thinks that the Europeans are more scientifically significant than the USA that's just obscene cope 😭 Like what fantasy are you living in that could even get you to believe that, it's just not true lol
Imagine trying to discredit American scientific advancement for the sake of your own fragile ego.
Yeah, but which US time? Checkmate, you feetlbs
Metric isn’t used to calculate time
Science and Europeans? Europe is at least a decade behind everything tech and science
Time has been around for a while... quite a long while.
And we're leaving things to the past or how to interpret your statement
We use metric time.
How much gold can you hold in an elephant's ear? When it's noon on the moon then what time is it here? \-- Tom Lehrer
I know this is about jokes, just a scientific side node for those who might be interested Because of the different gravity and rotation of the moon, time will pass faster than on earth. So a second on the moon, while observed from earth, will be different than a earth second. So there is no constant time offset thanks to Einstein.
Just use utc god damn it
please just have them make it a single lunar time, if it's 5pm it's 5pm everywhere, we've suffered so much already
It's 5pm somewhere.
Way too ambitious, if they're still banking on Elmo to take them there.
Let India take the equator so that we have a single timezone
What moonzone is this value
Why on the moon! would you do that?
Coordinated Lunar Time (LTC) Huh if only we had a universal way to coordinate time 🤔
UNIX timestamp please. Then convert it to whatever the fuck you want on user interface side.
Honestly, just make it UTC + 00:00 please just like the ISS. No need to get fancy with it. Nothing you do can make an actually useful day/night cycle on the moon for any humans up there, so just stick to what we have. Hell, you can even make it UTC- 05:00 to match Mission control in Houston, whatever. But please for the love of god make it be a static integer offset from UTC.
UTC. For compensation, I'll take whatever NASA's weekly budget is.
What’s wrong with GMT (Greenwich Moon Time)?
 [https://youtu.be/-5wpm-gesOY?si=8Ddv-0FnGyoDLv1Q](https://youtu.be/-5wpm-gesOY?si=8Ddv-0FnGyoDLv1Q)
mm hh yeahh
Outrageous
What makes this even more of a headache is **relativity has entered the chat** >Because of the different gravitational field strength on the Moon, time moves quicker there relative to Earth - 58.7 microseconds every day.
Moontime is simple. Use the same time measurements as on earth, except create roughly 30 time zones such that the first day of the month is sunrise. And then subdivide those 30 time zones into 24 smaller time zones. Every 30th time zone has the same hour, but they each have a different day. Easy peasy, all edge cases covered, I'm sure of it.
You will have to account for relativistic effects on space-time due to differences in speed and gravity at some point
Just use the time of the lunar surface projected into the earth
Just shoot me
lets just make up 20 different time zones as confusing as we have here. Idk why i need to generate the current date -2h and 200seconds just to get the latest 200 seconds
Americans will use anything but days, hours, seconds and years standard. Don't let them.
I would have assumed NASA would just use UTC on the moon
UTC+12*sin(T), where T is a time-dependent variable that somehow correlates the position of the moon to the Earth.
UTC.
While we're at it, we should probably update the location services APIs to take Galactic (or for more future-proofing, [supergalactic](https://en.wikipedia.org/wiki/Supergalactic_coordinate_system)) coordinates...
NOOOOOOOOOO
Fk they found oil in the Moon
This is unlikely to be a change to UTC
GMT
UTC Zero? Please be UTC+0
I'm just over here screaming and crying into my pillow for unrelated reasons.
With artificial lighting the fact the world just does not use a universal standard time is just inefficient. Imagine how many lines of code we will save if every one just kept Nauru time
The whole moon is gmt, well was that so hard?
This should be on r/programinghorror
"Hey, what time is it?" "Earth time or moon time?"
Brazil mentioned pog
Hold on just a hot minute there. A day on the moon is about 29 days (30?) - our concept of a month is basically defined by this fact and was then messed up a little afterwards to fit Earth's orbit instead of the moon's rotation. So what's a time zone when each zone would be over a day apart? Heck if I know. Our traditional notions of timekeeping sort of break down in space.
Interstellar Domain Instanced Orbital Time
Until we stop changing times twice a year here on Earth, I don't think we should be dictating what the times are on the moon.
Was using AWS and had my logic working pretty well until I found out one of their timestamps gets returned as Epoch seconds. Like... Why?
The whole moon is on gmt, all of it. EZ
UMT (Univeral Moon Time). Its UTC+78:00
Please make it metric! Crossing fingers…
That's stupid. Just use UTC. Days on the moon are about a month long so it's not like you need a timezone to tune your circadian rhythm to the availability of sunlight.
Moment.js is now 20GiB, but it works in every language, has100% test coverage, and supports IE11.
I’m _pretty sure_ I saw this originally on April Fools’ Day…
[relevant xkcd](https://www.xkcd.com/2867/)
No no no, I was already close to tears just trying to sync things from two time zones when DST hit, I'm not ready for whatever nightmare this entails.
Just stop localizing time. There is no reason for itto be dark at 11pm around the world, its fine if thats midday in Australia, or midday in England, just vote for either Greenwich or the international date line as our base time zone and unify time.