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Living on Mars Time
Roland Piquepaille writes "When NASA's rovers, 'Spirit' and 'Opportunity,' touch down on Mars next January, scientists and engineers in charge of the missions at the Jet Propulsion Laboratory (JPL), will start to experiment with a 90-day period of jet lag. Why? Because, as reports Astrobiology Magazine, 'a day on Mars is 39.5 minutes longer than a day on Earth.' To accommodate the requirements of interplanetary communication, during the mission the Spirit science and engineering teams will have to live on Mars time, in synch with the red planet's cycle of light and dark. This means that, here on Earth, they'll sometimes be working during daylight hours, and at other times they'll be working through the night. This summary contains more details and a screenshot of the Mars24 application, a Java program which gives you the time on Mars."
Have these people never had to work to a deadline before ???
:)
two words for them
JOLT COLA
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"Oh."
A Java Application to display martian time? That sounds like a Java 101 excersise :)
Although the screenshots do look pretty neat.
Which is, of course, totally and completely different from what we do as computer people.
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Will they also be learning to live with the Terrible Secret of Space?
Developed on Mac OS X. Cool! Seriously though, it will be interesting to see the engineers adjust to an ever changing schedule. And I thought 3rd shift was bad!
CDE open sourced! https://sourceforge.net/projects/cdesktopenv/
a day on Mars is 39.5 minutes longer than a day on Earth.
Great. This is a project-planner's fantasy. Forget offshore, we should move our software projects off-planet.
I once heard that, in test, the human body operates on a 25 hour cycle anyway, and we 'reset' our internal clocks ever day to fit in with the 24 hours of a day.
IIRC, tests were carried out where volunteers lived underground with no access to the outside world - no TV, windows, etc. They could call up to the surface to request books, games, food, but nothing that would allow them to work out any sence of time (no clocks either!). It was found that they reverted to a 25 hour day...
Shouldn't be too difficult for the scientists, or for colonization...
I don't see how this would be a problem. Several credible reports exist that say our natural body clock cycle is 25-26 hours, making the adjustment to "Mars time" rather painless.
...When are going to switch to the "Stardate" notation of time?
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Not everyone has a body clock that runs on an exact 24 hour cycle. Some people's circadian rhythms run as fast as 23 hours/cycle, some as slow as 25 hrs/cycle. JPL could test its employees for their natural cycle. A few days in a sleep test chamber quickly show which people tend to get up earlier and earlier each day vs. those that get up later and later. Then, they could selectively use people whose body clock matches that of Mars. Of course, I would still pity the families of the people that are on Mars time.
Two wrongs don't make a right, but three lefts do.
Why? Changing the length of such a fundemental unit of time (other than one Planck unit of time) without changing its name is sure to cause confusion.
Not to mention, each measure of time will have to multiplied by a number not very much greater or smaller than 1, possibly causing precision problems, in order to convert it between Earth seconds and Mars seconds.
While I applaud the effort to make it easier to count time on Mars - I think, that in the bigger picture, it is not a good idea to use different fundemental units of time.
Even in the Clarke's 3001, the Ganymedes ignored the local time and measured the time in Earth units. If I recall correctly, they measured time with respect to UTC on Earth, completely ignoring local time.
A day thats still 24 hours long, but 39 minutes longer than an earth day? Is that Earth or Mars minutes now? We have enough problems (rockets blowing up etc.) caused by converting between the dissimilar metric and imperial units - who exactly thought redefining minutes and seconds to be slightly longer on mars was a good idea? Thats going to lead to something very expensive.
...lets not forget that the European Space Agency's Mars Express mission has almost reached the red planet, and that the British-built Beagle 2 probe onboard will be touching down on Christmas Day, to begin its search for life. I for one am very excited!
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A day on Mars, which is known as a "sol," consists of 24 hours, just like a day on Earth. Each hour contains 60 minutes; each minute 60 seconds. There's nothing magical about that. Scientists simply got together and declared it to be so. But there's a catch. A martian second is a smidge longer than what you're used to on Earth. Think of it this way: Instead of counting, "One Mississippi, two Mississippi" count "One Mississippis, two Mississippis."
yes, because redefining the basic elements by which we measure time is SOOOOO much simpler than making a Martian day 24 hours and 40 minutes long...
A meter is defined as distanced traveled by light in a vaccum in an amount of time, is a meter longer on mars now?
Well, that dratted "24/7" slogan is definitely doomed on Mars.
Mars Time????
Is that Metric or is that Imperial?
I mean.. like.. shouldnt they wait to see if it actually lands this time?
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I wonder what comparable effects (2 moons?) on Mars have led to both planets having similar days.
Or, is this just how the Designers planned this particular planetary system?
The Law of Falling Bodies
I wonder when they'll adopt the 'time slip' as suggested by Kim Stanley Robinson in 'Red Mars':
The day has 24 'official' hours; the 39+ extra minutes are, well, extra: party time!
Say out loud: I'm an Aspie and I'm somewhat proud, I guess. Uh. Can I write an email in all caps instead? Hm...
I can see it now: special edition TiVo for people on "Mars time."
30 24 * * * /usr/bin/phone.home >/dev/null 2>&1
Just sleep in an extra 39 minutes every morning. It works for me!
One line blog. I hear that they're called Twitters now.
There have been lots of other posts about them changing the fundamental unit of time to do this, but what struck me is that they aren't using metric time. I would think that for a scientific endeavour such as this, where they are modifying the unit of time anyway, they would use a base-10 system instead of our current one.
I agree.
Frankly, given that we do all of our other work in base 10, I'm surprised scientists haven't used this as an opportunity to introduce a base-10 time system for mars (and the other planets as well).
1000 "metric seconds" (microsols) = 1 "metric minute" (millisol)
100 millisols = 1 "metric hour" (decisol)
10 decisols = 1 sol.
Convert between Martian time, Jupiter Time, Calliston Time, etc. via a simple coefficient (perhaps defined such that 1.0 yields earth standard time in base-10). Indeed, such a system could even be backported to the earth, should we ever have the desire. Given that the rest of our units of measure are in base 10, this makes perfect sense.
Of course, calendars do not lend themselves to base 10, but neither do they lend themselves to base 12 or base 60. In any event, that is no reason that basic temporal units, such as are used in physics (meters/second^2, etc) shouldn't be in the same base as the rest of our scientific units.
In addition to the easier kitchen-math of using base 10 over base 60, this approach would have had the added advantage of not being so easilly confusing: no one is going to confuse a second with a microsol, be it a microsol on Mars, on Jupiter, on Io, or even on Earth, while a 'martian second' vs. a 'terran second' is bound to sow all kinds of confusion over the next few generations.
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The moon and its tides repeat on a 24 hour 48 minute periodicty. That could explain the 25 hour period in absence of light.
Its biologically useful to have multiple clocks. This spreads out activity cycles, so that short period disaster, e.g. predator, wont wipe out everyone.
During my thesis write-up I was basically working as much as I could before dropping dead. My day cycle went from 24 to 30 hours with a 20 hour working period followed by 10 hours sleep. I reckon I wasn't meant to live on this planet ;-)
Of course, there are some drawbacks... quite often I'd be eating pizza and watching the tellytubbies or some other crap on TV before going to bed at some crazy hour like 10AM, but sometimes I would show-up at the uni during "normal hours" even enjoying a pint or 2 with my mates after work. That day, I would just call "friday". Problem is, when your friday falls on a sunday, there aren't many mates to enjoy a pint after work... I guess there were "good" and "bad" fridays :-)
Did that for about 6 months until the viva. Took ages to go back into a 24 hour cycle and still now (2 years after) I have to be careful not to push it too much during weekends otherwise my sleep is basically screwed for the entire following week.
People talk about this as though it were a new requirement, but some astronomers have done this before. I was involved in a project which used the old 300 foot telescope at Green Bank, WVA, which was only moveable in "longitude" -- for "latitude", we had to wait for our target to pass overhead. This meant we worked on sidereal time, but the cafeteria stayed on mean solar time. It was only a few minutes a day difference, but it was still pretty disruptive.
2*3*3*3*3*11*251
Kim Stanley Robinson, in his books Red Mars, Green Mars, and Blue Mars, had a really interesting system. Instead of keeping a 24 hour day and gradually getting out of sync w/ daylight, they add a 39 minute long "second" at midnight.
Did you mount a military-grade, variable-focus MASER on an unlicensed artificial intelligence?
in his book Emergence: The Connected Lives of Ants, Brains, Cities, and Software, Steven Johnson says that, for some reason, human's internal clock is based on a day 25 hours long. this clock is reset every morning when you wake up. this explains why i tend to get tired an hour later each day, until i force myself to correct it.
this would probably mean living on Mars would feel more natural than on Earth.
Of course, calendars do not lend themselves to base 10, but neither do they lend themselves to base 12 or base 60. In any event, that is no reason that basic temporal units, such as are used in physics (meters/second^2, etc) shouldn't be in the same base as the rest of our scientific units.
There's plenty of reason. Scientists prefer their choice of units to most naturally reflect the environment in which they're working. Kelvin is a more natural temperature scale for fundamental work, but Celsius, with 0 as freezing and 100 as boiling, is more natural in situations where water is important (like cooking and going outside). Particle physicists have one unit, the eV, which measures time, length, mass, etc. This wouldn't be particularly useful for measuring travel distance.
"86.4 ks from now" is not a useful way of refering to the same time tomorrow. This problem becomes much worse when you need to refer to several days away, since 0.7776 Ms is a horrible way to refer to 9 days. You might make the argument that the "day" is artificially chosen and not useful for measurement, but you would be sadly mistaken. For quite a while, at least, human life on this planet will revolve around a daily cycle. The sun still somewhat regulates our sleeping, and thus our work schedules.
If you try to remedy the problem by simply choosing the day as a fundamental unit and discarding the second, then you still run into the exact same problem we're discussing when you go to another planet. And even without interplanetary travel, you still have a problem when it comes to discussing years. Seasonal change affects our lives a great deal, so there is still value in maintaining a unit of time for a year.
Ugh. Any other Slashdotters want to contribute/correct me, please do :)
This has been proposed many, many times for use here on Earth. The metric-heads went gangbusters over it when Canada converted to metric back in the 70s, and it never took off, for obvious reasons:
Of course, calendars do not lend themselves to base 10, but neither do they lend themselves to base 12 or base 60
This here is the key. Our calender is (more or less) based on a logical observation of regular cyclical events in the sky. Our 12 months come from the cycle of the moon, of which we go through approximately 12 per year. The word "month" was originally "moonth", if you're curious. The problem, of course, is that nature didn't provide us with a nice 12 months of 30 days per month, so we have this hodepodge of units. We also don't have an exactly 365-day (which is base what, anyway?) year, but we manage, because measuring days is just about the most natural thing we can do.
As for minutes/seconds, this goes back to circular clock faces, and possibly sundials. I forget the exact mathematical reasoning behind it, but a circle just doesn't divide into base-100 nicely. Unless my professors just made this one up, or I'm remembering wrong, it's been a long time!
In short, the way we measure time is partly biological, and partly historical. I've managed to find pretty compelling reasons for most of it over the years, but yeah, like any measurement system, it's mostly arbitrary.
Endless arguments over trivial contradictions in books written by ignorant savages to explain thunder in the dark.
for years and years. The folks that man our nuclear subs live on an 18-hour cycle. For example, they get up a 7AM, stand watch from 8AM until 2PM, eat, shower (sometimes!), conduct maintenance, get some sleep, and then get up at 1AM. Then they stand watch from 2AM until 8AM, and so on. They do this for 2-3 months at a time.
Let me tell you, you get really, really tired at the end of this!
There are only two possible explanations for this phenomenon:
I'd say either one strongly implies that aliens have been seriously messing with us before the advent of civilization. There are certainly many mythological cosmologies that feature humans arriving from somewhere else -- are there any that could be taken to imply a change in the Earth's orbit?
A) Complaints about redefining the second:
Days, seconds minutes, etc are all based on SOLAR cycles. We aren't redefining them, Mars' rotation is! We use UTC as that standard time unit and UTC is well defined, but it isn't linked to solar cycles on Mars so it's useless to keep track of Martian days with.
B) Complaints about why:
Read the article. The rover can only transmit at a time of day when the sun is up and Earth is in the sky. That is the same time of day on Mars every Martian day, but on Earth, due to the differences in rotation, shifts 39.5 minutes later each Earth day (no jokes please, you know what I mean). All NASA is saying is that mission controllers will need to do their jobs 39.5 minutes later each day because that's when the probe with be transmitting. It's not that hard to figure out! Yeesh.
I think some people may have no circadian cycles. I sleep a random number of hours, and am awake for a random number of hours each day.
This week's rough 'awake' hours have been like.. 32, 9, 29, 11, 17, 12.. and 'sleep' hours have been like.. 7, 4, 16, 11, 12, 6, 9.
I live quite easily in this situation (since I work for myself). Daylight appears to have no effect, unless I woke up at, say, 9pm.. in which case I usually have a wave of tiredness hit me when daylight comes.
Does this mean I have no rhythm, or a heavily distorted one?
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I always thought the way that this extra 40 minutes was handled in Kim Stanley Robinson's Mars trilogy (Red Mars, Blue Mars, Green Mars) was great.I can't remember what they call that time period- but they just leave it off the clock. Every night at midnight, the transition from 12:00 AM to 12:01 AM takes 39.5 minutes rather than only 1. That way, you can go to bed later than you should've and still get a decent rest. :)
For any of you interested in Mars colonization, I highly reccomend the books. I've yet to read the last of the trilogy, but Red Mars was absolutely amazing. The second book was pretty good too, but it's hard to follow up something like the first. KSR portrays a very realistic near-future, and a lot of the technology it'd take in the book's version is already here. I think KSR serves on some various NASA committes regarding the future manned mission to Mars, etc.
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Here is a GPL PalmPilot port I wrote of Mars24 (using the actual time code, just a different UI):
MarsClock.
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