OpenBSD adds support for Coordinated Mars Time(marc.info)
marc.info
OpenBSD adds support for Coordinated Mars Time
https://marc.info/?l=openbsd-cvs&m=161730046519995&w=2
65 comments
Naming something that only works on one planet "Universal Coordinated Time" was a mistake.
This has caused so many mistakes and accidents, you’d get the impression the people who came up with that name have never left their solar system.
"This has made a lot of people very angry and has been widely regarded as a bad move."
Don't panic!
It doesn't matter till we'll be actually able to settle down on Mars permanently, I guess and differentiating from Mars local time and its time zones will be an issue (and all parties involved in colonization will agree that Airy-0 crater will remain the 0° longitude equivalent as proposed by IAU).
Beside, the perspective matters - for people on Earth it can be still UTC, for those on Mars it can be whatever term they'll find most suitable.
The scifi series Babylon 5 with its titular station used Earth Standard Time [1] while being placed in Epsilon Eridani system. That doesn't sound bad, I think.
The another issue the future colonists will have to deal with will be how to track days, months and years. There's Thomas Gangale's suggestion that does look interesting [2].
[1] - https://babylon5.fandom.com/wiki/Earth_Standard_Time [2] - http://ops-alaska.com/time/gangale_mst/darian.htm
The scifi series Babylon 5 with its titular station used Earth Standard Time [1] while being placed in Epsilon Eridani system. That doesn't sound bad, I think.
The another issue the future colonists will have to deal with will be how to track days, months and years. There's Thomas Gangale's suggestion that does look interesting [2].
[1] - https://babylon5.fandom.com/wiki/Earth_Standard_Time [2] - http://ops-alaska.com/time/gangale_mst/darian.htm
> It doesn't matter till we'll be actually able to settle down on Mars permanently
Mars is the least useful planetary body in the Solar System for human colonization, so that time may well be "never".
Mars is the least useful planetary body in the Solar System for human colonization, so that time may well be "never".
It's the best thing we have in our neighborhood beside the Moon; Venus is easier to reach but not very welcoming when it comes to atmospheric pressure and temperatures.
You don't need to land on Venus' surface; airships in the atmosphere are the closest thing to Earth in the Solar System.
The problem is that there is nothing useful on Mars and its location sucks. Any other planetary body makes more economic sense.
The problem is that there is nothing useful on Mars and its location sucks. Any other planetary body makes more economic sense.
I think one of the most compelling aspects about Mars is the thin atmosphere which enables a high degree of visual clarity, which is very appealing to humans. The atmosphere of Venus is very murky.
Mars is not the Mojave Desert; it's far away from the sun and always dark and cold. I'd think anybody going to Mars for the aesthetics would be disappointed.
> The problem is that there is nothing useful on Mars and its location sucks. Any other planetary body makes more economic sense.
There’s nothing worth the shipping cost anywhere off the surface od the Earth, and all the rest of the planets are much worse locations than Mars. (Venus maybe slightly better if you are only getting to/from high atmosphere, but that has the “there’s nothing worthwhile there” problem more than Mars does.)
There’s nothing worth the shipping cost anywhere off the surface od the Earth, and all the rest of the planets are much worse locations than Mars. (Venus maybe slightly better if you are only getting to/from high atmosphere, but that has the “there’s nothing worthwhile there” problem more than Mars does.)
The problem with Venus is that it's exceedingly difficult to get local resources. Mining on Venus is practically impossible. Anything you can't suck out of the atmosphere basically needs to be shipped in from off-world.
> Venus is easier to reach but not very welcoming when it comes to atmospheric pressure and temperatures.
Or composition; its also not easier to reach (or return from) if you are going to the surface.
Or composition; its also not easier to reach (or return from) if you are going to the surface.
> Mars is the least useful planetary body in the Solar System for human colonization
I suppose you could construct criteria and assumptions that would support that conclusion, but I can’t see a reasonable set where that works out.
I suppose you could construct criteria and assumptions that would support that conclusion, but I can’t see a reasonable set where that works out.
You can live on Pluto instead if you insist.
I understand the appeal of having time tracking systems related to easy noticeable celestial bodies movement, but when such enlargement to a multi-planetary context happen, it makes more sense to think of an entirely new system altogether. Even more so considering that almost everyone relies on tool based time tracking for their activity instead of looking up at the moon or the sun. The first direction towards a solution that comes to mind is about a natural-units derived system, like one based on Planck time or something.
> It doesn't matter till we'll be actually able to settle down on Mars permanently
Why? There's plenty of computers in Mars right now and they use martian time already [0]. It's not as if OpenBSD have invented anything new, they just adapted the OS to existing practices.
[0] https://en.wikipedia.org/wiki/Timekeeping_on_Mars
Why? There's plenty of computers in Mars right now and they use martian time already [0]. It's not as if OpenBSD have invented anything new, they just adapted the OS to existing practices.
[0] https://en.wikipedia.org/wiki/Timekeeping_on_Mars
Yes, computers that are aboard rovers and landers which are being used for scientific purposes. Nobody needs timekeeping on Mars beside folks at mission centers or enthusiasts - even I don't know how long Perseverance is on Mars in Sols and what's its current Airy Mean Time (I'm aware its there and doing good atm).
Now, if we'd be there already for decades or even centuries with permanent settlement then perhaps we'd have some date and time formats that would be similar to what we're having on Earth (or maybe they'd use the exotic decimal time) and I wouldn't be even writing the parent comment in first place.
Now, if we'd be there already for decades or even centuries with permanent settlement then perhaps we'd have some date and time formats that would be similar to what we're having on Earth (or maybe they'd use the exotic decimal time) and I wouldn't be even writing the parent comment in first place.
> Nobody needs timekeeping on Mars beside folks at mission centers
Well, these people can use OpenBSD now ;)
Well, these people can use OpenBSD now ;)
One issue with these attempts to make a calendar for mars is that they assume you can equally divide the year and still get months that match up with the seasons. Mars has an eccentric orbit, so that's not a good matchup. You either accept that th calendar won't be good for tracking the seasons, or make a calendar with uneven months.
Considering that the weather outside will kill you year-round on Mars, debate is of course rather academic...
Considering that the weather outside will kill you year-round on Mars, debate is of course rather academic...
Uh, rename to GMT.
Should we go ahead and make a SSCT (solar system coordinated time) as well?
That way I don't have to constantly be converting lunar timestamps, mars timestamps, etc. back to UTC (or the coordinated time of whichever celestial body I'm currently on) in order to paint a timeline of when events happened between my different devices spread out across the solar system.
That way I don't have to constantly be converting lunar timestamps, mars timestamps, etc. back to UTC (or the coordinated time of whichever celestial body I'm currently on) in order to paint a timeline of when events happened between my different devices spread out across the solar system.
Wouldn't that need accounting for relativity? Distance to the gravity well (sun) affects the physical passage of time for you. Perhaps that's doable, but you can't count a sequence of numbers off and call it a day.
Time is local to a region though - there isn't any "Solar System Coordinated Time".
I guess pulsars may be our best bet for a universally coordinated time? We can detect the passage of time in a gravity well and create a well-centric system if need be!
Are you saying that a given pulsar acts as a giant sky clock? And that because it is far away — for some large value of far — it means that any clock inconsistencies across the solar system can be compensated for?
Pretty much, yes! Obviously the speed of light and orbital motion/distances make things tricky but not impossible.
I think I’m also saying that since time passes at different rates in different gravity scenarios, a single external reference may be the best way to coordinate time… even outside of our solar system.
I think I’m also saying that since time passes at different rates in different gravity scenarios, a single external reference may be the best way to coordinate time… even outside of our solar system.
Actually, “single external reference” might be wrong here. Using multiple pulsars might give us a better fix for our position +time solution across large distances.
Even cooler is that this has apparently and unsurprisingly already been explored.
These replies are intriguing, thanks. Do you have some good links / references I can follow?
Pulsar positioning system:
https://arxiv.org/pdf/1704.03316.pdf
While not a primary source, it's still an answer to absolute time from pulsars: https://physics.stackexchange.com/questions/175981/can-you-u...
While not a primary source, it's still an answer to absolute time from pulsars: https://physics.stackexchange.com/questions/175981/can-you-u...
Well, no, pulsars periods drift due to change of alignment and emission process over time. Thought special and general relativity will drive any "global/solar system/galaxy"-wide precise time useless on long term anyway. The best is to keep track of long enough common measures ("day", "month") with decimal/fractions being connected to actual local times.
The Earth “day” also drifts over time. If you’ve ever thought today was longer than the last, then you are statistically correct!
I'd say define a "cycle" as greatest common divisor of all planets' rotation periods. Make it an equivalent of "solar system day/hour" or something.
The problem is these orbital periods are generally not rational multiples of each other, so their GCD is undefined (or 0, in a sense).
Some exceptions to this exist due to orbital resonance: Pluto and Neptune are in 2:3 resonance, and in the Jovian system Ganymede, Europa, and Io are in 1:2:4 resonance.
Some exceptions to this exist due to orbital resonance: Pluto and Neptune are in 2:3 resonance, and in the Jovian system Ganymede, Europa, and Io are in 1:2:4 resonance.
"Only two remote holes in the default install, in a heck of a long time, now across two planets!" :)
I wonder how time zones on other planets would work once relativistic time dilation has to be considered. Add a multiplier to how fast your clock ticks? I suppose satellites should have this problem already resolved but only in Earth's sphere of influence.
Also simply travelling to Mars would desynchronize the time and would have to be resynced.
Also simply travelling to Mars would desynchronize the time and would have to be resynced.
GPS systems have already had to solve this and from what I can make of it, its a fully general solution that could be ported to mars etc. https://jimlambskeptic.com/gps-and-time-dilation/
(fire upon the deep) Just use raw seconds with kilo and mega.
The clock was conceived to align human periodicity to the periodicity of earths day and night cycle (e.g. waking up at the same time every day) but also to synchronize the people around you (e.g. working at the same time every day).
When working in an intertimezonal setting, however, that concept of a 24h day felt very weird. While the day and night cycle indeed is roughly 24h, the human productivity cycle appeared longer in duration as some people were having a normal morning work start at 1:00am on my clock and 8:00am their time.
This shifts the mental model to what it means for deliverables to be produced “today” or “on day X”. Is it their day or is it my day? It also shifts the perception of much work per day we are putting in, while on the paper it just is a simple per 24h division. Bob worked an 8h shift in a 24h workday which is in a 24h + 8h + 8h (arbitrary numbers chosen only for visualization) global workday, so did he now work enough? Did he work “all day”?
I came to the realization that a 24h long workday in such a setting feels arbitrary and off. It should be longer, but how long exactly.
This will only get worse once we have clocks running faster the further away we get from the gravitational field of the Sun or work on planets or moons with different day/night cycles.
How would one do it inside an Asteroid Mining Colony?
When working in an intertimezonal setting, however, that concept of a 24h day felt very weird. While the day and night cycle indeed is roughly 24h, the human productivity cycle appeared longer in duration as some people were having a normal morning work start at 1:00am on my clock and 8:00am their time.
This shifts the mental model to what it means for deliverables to be produced “today” or “on day X”. Is it their day or is it my day? It also shifts the perception of much work per day we are putting in, while on the paper it just is a simple per 24h division. Bob worked an 8h shift in a 24h workday which is in a 24h + 8h + 8h (arbitrary numbers chosen only for visualization) global workday, so did he now work enough? Did he work “all day”?
I came to the realization that a 24h long workday in such a setting feels arbitrary and off. It should be longer, but how long exactly.
This will only get worse once we have clocks running faster the further away we get from the gravitational field of the Sun or work on planets or moons with different day/night cycles.
How would one do it inside an Asteroid Mining Colony?
How exactly would you ensure nanosecond accuracy of time between earth and mars? Does Nasa just run ntp back to earth? Or really expensive atomic clocks made out of special metals?
Assuming this is not an April Fools joke, I guess you wouldn't. Probably during travel measurable relativistic time difference has already set in and the nanosecond sync to earth might already differ by that. (If you manage to sync with ns precision anyways, that would be more an earth-like time/clock :)) Also days are a bit longer on Mars so it would be possible to keep in sync with local days.
https://en.wikipedia.org/wiki/Hafele–Keating_experiment
https://en.wikipedia.org/wiki/Hafele–Keating_experiment
I don't think relativistic effects are that great of a problem; I'd imagine that we know the orbital and gravitational characteristics well enough to do pretty decent compensation for relativity. That being said, nanosecond accuracy might be out of our reach, considering that it's bit of a challenge to get that level of accuracy on even on Earth.
Also shipping atomic clocks to space is not all that outrageous idea. Few years ago NASA lauched Deep Space Atomic Clock[1], which is exactly what it sounds like. Also modern "chip scale" atomic clocks[2] are pretty small and low power, so I would not be surprised to see those in future missions.
[1] https://www.nasa.gov/mission_pages/tdm/clock/index.html
[2] https://www.microsemi.com/product-directory/embedded-clocks-...
Also shipping atomic clocks to space is not all that outrageous idea. Few years ago NASA lauched Deep Space Atomic Clock[1], which is exactly what it sounds like. Also modern "chip scale" atomic clocks[2] are pretty small and low power, so I would not be surprised to see those in future missions.
[1] https://www.nasa.gov/mission_pages/tdm/clock/index.html
[2] https://www.microsemi.com/product-directory/embedded-clocks-...
A) Is this an April Fools joke?
B) If it’s not an AFJ then it sounds like an incredibly unnecessary set of potential bug creating code changes for a security focused operating system!
B) If it’s not an AFJ then it sounds like an incredibly unnecessary set of potential bug creating code changes for a security focused operating system!
[deleted]
On the question A, I am torn. It might be or it might be not.
That said, there already are Linux machines operating on Mars and we can expect the number of computers working there to increase substantially within 10-20 years. That means that BSD and other OSes are going to have to implement some kind of Martian timekeeping anyway.
So perhaps it is better to start now, when the low-hanging bugs can be ironed out without accidentally bricking an important piece of machinery on another planet.
That said, there already are Linux machines operating on Mars and we can expect the number of computers working there to increase substantially within 10-20 years. That means that BSD and other OSes are going to have to implement some kind of Martian timekeeping anyway.
So perhaps it is better to start now, when the low-hanging bugs can be ironed out without accidentally bricking an important piece of machinery on another planet.
They actually had me until "Bump the major on every single base library as many interfaces change."
It's interesting that time and date semantics are based on the rotation and orbits of planets.
A truly universal time should probably be based on the orbits or other oscillations of atoms, possibly away from a gravity well and at a precise temperature.
A truly universal time should probably be based on the orbits or other oscillations of atoms, possibly away from a gravity well and at a precise temperature.
Our solar system is rotating within our galaxy, presumably you have to travel quite a bit before being „away from a gravity well“. But at that „location“, there may be a lot of relative velocity to our solar system, so there will be time dilation effects - for us or them, depending on your reference frame.
...One of the first things you learn in special relativity is that there are no preferred reference frames, I still have trouble wrapping my head around that one.
...One of the first things you learn in special relativity is that there are no preferred reference frames, I still have trouble wrapping my head around that one.
For ancient people who constructed the first timekeeping systems, observable changes in the environment (light/dark, frost/rain) were of crucial importance. Sheer cultural inertia since then means that we still use Roman letters and Babylonian time units. The cost of change would be too high, not to mention the risk of some countries refusing to go along. Well, almost certainty, not a risk.
A new "truly universal time" could end up, paradoxically, as a niche thing only used by hardcore enthusiasts, much like all the attempts to create an artificial universal language (volapuk, esperanto). Heck, we could not even get the whole world to adapt SI units of measurement.
A new "truly universal time" could end up, paradoxically, as a niche thing only used by hardcore enthusiasts, much like all the attempts to create an artificial universal language (volapuk, esperanto). Heck, we could not even get the whole world to adapt SI units of measurement.
(where/how) can I see the actual patch set, not only summary of modified files?
I have not worked with cvs, so it's non trivial to figure out.
I have not worked with cvs, so it's non trivial to figure out.
This is an April Fools joke, so there’s nothing to see.
But if you want a browsable interface to OpenBSD’s repos (no CVS knowledge required), you can use either the project’s CVSweb [1] or the GitHub mirrors [2].
[1]: http://cvsweb.openbsd.org/cgi-bin/cvsweb/
[2]: https://github.com/openbsd
But if you want a browsable interface to OpenBSD’s repos (no CVS knowledge required), you can use either the project’s CVSweb [1] or the GitHub mirrors [2].
[1]: http://cvsweb.openbsd.org/cgi-bin/cvsweb/
[2]: https://github.com/openbsd
It's amazing and embarrassing how far I had to scroll through the comments to realise this was an April Fools. Tbf it's 4:43 on the 2nd of April where I am now, but still