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OpenBSD Adds Support for Coordinated Mars Time (MTC)
- znpy 6y agoI wonder if SpaceX has anything to do with this.
- znpy 6y agoI'm getting downvoted... Of course I forgot today is April 1st.
- yellowapple 6y agoI know this is probably an April Fool's joke, but I'd be thrilled if this was real.
- BuildTheRobots 6y agoI'm almost certain it's a joke, the question is for how much longer? The crypto interoperability issues are amusing, thiugh I do seriously wonder how you deal with anything from a 10 to 40 minute round trip time.
- ronsor 6y agoYou have caching servers and set really, really long timeouts.
- wongarsu 6y agoThe same way we deal with speed-of-light delay on earth: CDNs, asynchronous protocols like email, or just ignoring it when we can get away with it (e.g. "instant" messaging). SSH might be a bit tricky, but just pretend your system on mars is a production server and send it a tested bash file (using any of your favorite automation tools).
- BenjiWiebe 6y agoWhat protocol do you use to securely send the bash file?
- livueta 6y agoSomething that doesn't rely on round trips for error correction, I guess. AFAIK bandwidth is limited but is overall less of an extreme constraint than the RTT. Seems like a good use for forward error correction / sending parity data, like Reed-Solomon.
- karmanyaahm 6y agoNot exactly a protocol but interesting to read https://public.ccsds.org/default.aspx https://public.ccsds.org/default.aspx
- vsareto 6y agoWriting some test software based on Martian time might be a good way to prevent some DateTime issues when we do start living there.
- korethr 6y agoThe best April Fools jokes are the ones with enough plausibility that they _could_ be real.
- jamal-kumar 6y agoImagine reading: "DANGER: ABI incompatibility. Updating to this kernel requires extra work or you won't be able to login: install a snapshot instead" and raging
- Fern_Blossom 6y agoSame here, this is so far the best one yet. Far better than VW's shitty attempt. Though, it dawned on me, Mars could have real time zones. Not the stupid political mess we have today. Perfect, logical longitudinal time zones from the get go. That right there is more than enough reason for me to leave this planet. But let's be honest, Mars will be colonized, politics will arise and the same fuckery will happen eventually.
- elygre 6y agoIf they are zones, how can they be perfect? The middle might be, but anywhere else will be imperfect.
- yellowapple 6y agoYou're right. We need to constantly adjust our clocks depending on exact longitude.
- midasuni 6y agoAnd velocity. And altitude.
- monocasa 6y agoBetter yet, no time zones. Just one clock for the planet.
- jakear 6y agoObligatory https://qntm.org/abolish https://qntm.org/abolish
- monocasa 6y agoWhen you're already destroying enough of the legacy timekeeping systems by switching to a planet without a 24 hour day, most of those arguments lack muster. Also, don't call people out of the blue and expect them to pick up anyway. Maybe your uncle had to work late and is sleeping even though the sun is technically out.
- Zenst 6y agoIt certainly does raise a forward thinking issue and that is networking across planets and TZ handling. TZ's are already a PITA what with leap seconds. Then there is defining standards on Mars, 24hour days kinda not going to translate, so again, more forward thinking needed. As for Mars GPS, bit of a way off, but I'm sure the good old atomic clocks will work. I guess the job title of "Systems Engineer of Time" may become a reality one day after all.
- seiferteric 6y agoKind of makes me wonder about local time on a space ship going some significant % of the speed of light. Time itself would be at a different rate than back home. Perhaps we need to introduce the concept of a space-time zone.
- wongarsu 6y agoThe most practical solution is probably to introduce a global time beacon, like a satellite broadcasting it's own time, or everyone counting the flashes of some known pulsar. Then you have one time reference everyone agrees on, it just ticks at different speeds depending on how fast you are moving. Luckily so far the practical propulsion concepts we have max out around 10% the speed of light for reasonable amounts of propellant, so we have a couple decades left to figure this out.
- zokier 6y agoWe have few time standards that already take relativity into account: https://en.wikipedia.org/wiki/Barycentric_Dynamical_Time https://en.wikipedia.org/wiki/Barycentric_Dynamical_Time https://en.wikipedia.org/wiki/Barycentric_Coordinate_Time https://en.wikipedia.org/wiki/Barycentric_Coordinate_Time https://en.wikipedia.org/wiki/Geocentric_Coordinate_Time https://en.wikipedia.org/wiki/Geocentric_Coordinate_Time
- deleted 6y ago[deleted]
- nwallin 6y agoA time system useful on Mars needs additional consideration; considerations we haven't given it yet. It requires more thinking than just time zones. The various things we've sent to Mars haven't had any need for a colloquially time; they're computers, they just know that 21,872 seconds or whatever into the day is that far into an 87,755 second day and that's good enough to calculate shadow angles and expected solar panel efficiency from. If we were to build a colony on Mars with normal people doing normal everyday things, we need something more than that. The first question we want to ask ourselves is, do we want to keep the SI defined second? If we don't care, then we have free reign to do whatever we want. We can define a Mars second to be 1/86,400th of a Mars day, and keep the 24 hour, 60 minute, 60 second time system we use on Earth. Or we switch to a metric time system, with a 10 hour day, 100 minute hours, 100 second minutes. Or a 1 day long day, and deci, ceni, milli, micro days. Or whatever. If we want to keep SI compatibility, we need to keep the second. The Martian solar day is 87,755.224 seconds long. 87,755 factors into 5^2 * 53 * 67. So we can do 25 hours per day, 53 minutes per hour, 67 seconds per minute to give an 87,755 second day. Unfortunately there would need to be a leap second once every 4-5 days. Then there's the question of the calendar. Perhaps fortunately, this gives us the opportunity to restart from scratch, because the calendar we use is such a goddamned clusterfuck, even worse than our time system. Unfortunately, the number of days in a Martian year (668 and change) does not lend itself to a clean division into tidy periods. You could have 23 months of 29 days each, with each month having 4 7 day weeks plus one holiday. This will give you a 667 day year. Add another annual holiday at the beginning of the year, plus an optional leap-holiday in the middle of the year. Or you could split it up into 37 months of 3 weeks, each with 6 days. This gives you a 666 day year, so sprinkle in 2-3 bonus holidays per year. There are a lot of considerations. It needs to be given more thought. Hopefully more thought than we've given to Earth's timekeeping systems.
- sfblah 6y agoIt mentions the days being longer, but what about the years? What even constitutes a year on Mars? Seems like more thought needs to go into how this would work if/when we become interplanetary. Assuming knowing where you are in the year has any value on Mars, we'd want some way to track that. I wonder also how this would work on the moon.
- yellowapple 6y agoProbably best to just drop the notion of "days", "years", etc. entirely, and instead just track the number of kiloseconds, megaseconds, etc. since the Unix Epoch.
- yjftsjthsd-h 6y agoI was under the impression that the OS did only track time in seconds since the epoch, and whenever you see something else it's just the software translating for human convenience. If that's the case, then it this doesn't really make sense; humans will want something friendlier than epoch time on Mars, too.
- bonzini 6y agoSort of. Unix time does not count leap seconds, all days are 86400 seconds long in Unix time. So the actual number of seconds since the epoch is a bit larger than what time() returns. I don't know how Windows deals with leap seconds (its epoch is in 1601 or something like that). Edit: it doesn't, the clock goes 1 second ahead of UTC and it's then fixed by NTP.
- pedrocr 6y agoSo time() is actually days since epoch with 1/86400 precision. That makes the Google solution to smear leap seconds with NTP instead of making them explicit make even more sense.
- zrm 6y agoSince the Unix Epoch where? Isn't being on another planet going to have to deal with the relativistic passage of time?
- HugoDaniel 6y agoAlien technology
- lsllc 6y agoPlease, let's not have SST on Mars! (Sol-light Savings Time)
- cproctor 6y agoThis could really bite you: > It is currently not possible to use ssh to login between systems on MCT and any earth time zone
- cphajduk 6y agoneed to set the SSH timeout to 44 minutes.
- koolba 6y agoAlso make sure you’re not behind a NAT that drops what it thinks are idle connections. Full handshake requires a few hours of round trips.
- brutal_chaos_ 6y agoLet's do some math! According to the SSH handshake described here[1], I believe there are 6 one-way trips. Given communication times according to this[2], we can average a one way trip to be about 11min. 6 trips x 11 min each: That is 66min for the handshake. @_o [1]: https://techieuniversity.com/ssh-work-flow/ https://techieuniversity.com/ssh-work-flow/ [2]: https://www.mars-one.com/faq/technology/how-does-the-mars-base-communicate-with-earth https://www.mars-one.com/faq/technology/how-does-the-mars-ba...
- ianlevesque 6y agoNeed 0RTT like TLS!
- jamesfmilne 6y agoI bet the MCRN Rocinante’s computers are running OpenBSD.
- HeckFeck 6y agoIt's the only OS the protomolecule couldn't breach.
- gbrown_ 6y agoDoors and corners...
- bpodgursky 6y agoTo be pedantic, it was only the MCRN Tachi. "Now" it's just the Rocinante.
- lsllc 6y agoSo, what you're saying is that 2307 is going to be the year of the OpenBSD Desktop? (on Mars at least, the Earthers probably use NetBSD and the Belters FreeBSD).
- arp242 6y agoGiven how easy the Rocinante can be hacked to explode or arbitrary change transponder codes, I'm not sure if it's good advertisement for OpenBSD.
- walrus01 6y ago
- haddr 6y agoWhat about Belters?
- gbrown_ 6y agoFor Beltalowda!
- 082349872349872 6y agoJudging from the extant lang belta vocabulary, Belters are likely on an ISO week date calendar. They have 7 weekday names but don't seem to bother with our months, and they celebrate (a presumably earth calendar based) New Year. (calculating new years day relative to week 1 is probably for them the introductory CS equivalent of calculating easter for us. Seritenyidiye, "a 30-day", exists as a word for month, but probably refers to the earth concept, among those unlucky enough to have to interface with earth calendars.) Beltalowda showxa ere tim wit: https://en.wikipedia.org/wiki/ISO_week_date https://en.wikipedia.org/wiki/ISO_week_date keya? Beltalowda tili du pati (wit walowda walowda dansa unte walowda walowda rowm unte da adewu "Piyat Minut"?) fo Yitim unte showxa ere Mundiye, Tusidiye, unte kopeng. Amash beltalowda na tenye wowt fo "months" tumang. Imalowda tu inya, tu "legacy", sasa ke?
- vsareto 6y agoThey refer to time as shifts as well, presumably since work is so crucial. So it seems to imply the shifts are a regular length of time, so a "day" for a worker would be from the beginning of their shift to the beginning of their next shift. It's a little less clear with the Earth/Mars military. It's easy to use 8 hours for a shift like we do (and 8 hours for sleep), but our shifts are based around day/night, sleep cycles, and our human limits for work within Earth's gravity. That could change on Mars though. Since there won't be weather seasons or agriculture for a long while, work shifts will likely have a bigger influence on the decision rather than the reasons we have them on Earth.
- imwm 6y ago"mars can't wait" lol
- kevwil 6y agoHonestly, no idea if this is an April Fool's Day prank or not. Seems reasonable, but inconsistent naming makes me suspicious.
- wongarsu 6y agoCoordinated Mars Time (MTC) is an actual thing [1]. The abbreviation follows from UTC, which is abbreviated that way because English speakers wanted CUT (coordinated universal time) and French speakers wanted TUC (temps universel coordonné), so we compromised on an abbreviation that works in neither language (I wish I was joking). The commit going on to call the config TZ=MCT could totally be a typo that will persist for eternity, just like the "referer" header. 1: https://en.wikipedia.org/wiki/Timekeeping_on_Mars#Coordinated_Mars_Time https://en.wikipedia.org/wiki/Timekeeping_on_Mars#Coordinate...
- anthk 6y agoWell... https://astro-gr.org/openbsd/ https://astro-gr.org/openbsd/
- rzimmerman 6y agoIt’s technically even more complicated than just scaling the day/seconds by to match a Martian sol. There are relativistic corrections that add up over time (Earth clocks would observe Mars clocks ticking at a different and non-constant rate). Good thing this is real :)
- fsh 6y agoThis is already the case on earth. UTC is defined at sea level and clocks run faster at higher elevations due to the lower gravitational redshift. This effect is easily observable with atomic clocks and has to be taken into account in any accurate clock comparison.
- kadoban 6y agoThat is not taken into account in timezones though, because it would depend on where you live. For MTC it probably is accounted for to some extent.
- hedora 6y agoThis was a plot point in Cory Doctorow’s Martian Chronicles: https://escapepod.org/2019/10/03/escape-pod-700-martian-chronicles-part-1/ https://escapepod.org/2019/10/03/escape-pod-700-martian-chro... Disclaimer: Mostly just posting this to plug Escape Pod. No affiliation, but it’s one of my favorite short fiction podcasts.
- Zenst 6y agoThe design needed to accommodate leap seconds, https://en.wikipedia.org/wiki/DUT1 https://en.wikipedia.org/wiki/DUT1 due to planetary rotation adjustments, would be fun. So much of how we define time is rooted in the Suns movement. Then you start to get the new factor of planetary distance wobble adjustments. Which will be fun as you start to add https://en.wikipedia.org/wiki/Three-body_problem https://en.wikipedia.org/wiki/Three-body_problem into time models.
- gerdesj 6y agoWe already had GMT which ended up being called UTC - "Universal". If we'd stuck with GMT or defined E(arth)TC or similar, then MTC would make sense. I do like it though, good to see some innovation in the AFD jokes department.
- zeristor 6y agoWhat about leap seconds for Mars?
- vortico 6y agoMy sleep schedule has a ~25 hour period, so I'd actually use this. :) Been doing it for 20+ years. Most of 2021 I've awakened around 07:00 MTC. It's 10:27 as I write this, so I've been awake for about 3 (Mars) hours. http://marsclock.com/ http://marsclock.com/