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Adjusting To a Martian Day More Difficult Than Expected

Posted by Soulskill on from the not-as-bad-as-adjusting-to-a-neptunian-day dept.

schwit1 writes: Research and actual experience have found that adjusting to the slightly longer Martian day is not as easy as you would think. "If you're on Mars, or at least work by a Mars clock, you have to figure out how to put up with the exhausting challenge of those extra 40 minutes. To be exact, the Martian day is 24 hours, 39 minutes, and 35 seconds long, a length of day that doesn't coincide with the human body's natural rhythms. Scientists, Mars rover drivers, and everyone else in the space community call the Martian day a "sol" to differentiate it from an Earth day. While it doesn't seem like a big difference, that extra time adds up pretty quickly. It's like heading west by two time zones every three days. Call it 'rocket lag.'"

32 of 135 comments (clear)

  1. So live underground by Anonymous Coward · · Score: 4, Insightful

    ...and keep all the lighting on a 24 hour cycle. All the drawings I see of colonies on the moon or Mars all have buildings on the surface. Don't they both have cave systems? Just seal those off and who cares about the outside climate/seasons?

    1. Re:So live underground by Anonymous Coward · · Score: 5, Funny

      What every basement-dweller already knows.

    2. Re:So live underground by pr0fessor · · Score: 4, Insightful

      I think the biggest problem would be those on the mars days are here on earth and all the life around them is moving on the regular earth cycle... I can't have lunch at my favorite restaurant, go to the bank, etc... because my days are out of sync. Those people in the Arctic Circle are all on the same clock as businesses and everyone else around them.

    3. Re:So live underground by Ronin+Developer · · Score: 2

      This is no different that what submariners experience - with no natural light, they move to an 18 hour day (6 on 12 off). Contrast this to driving across the ocean in a ship and traversing the various time zone. The would adjust things on the ship so as to try to minimize the effect. However, it still sucked.

      BTW, the moon is also tidally locked with the Earth with it's rotation period and orbital period matching almost exactly 1:1. That's why the moon never seems to rotate from our perspective.

    4. Re:So live underground by Anonymous Coward · · Score: 2, Insightful

      This is no different that what submariners experience - with no natural light, they move to an 18 hour day (6 on 12 off).

      That is a forced schedule. There have been a couple of experiments with groups of people isolated in a mountain to see how people adjust when no sunlight and contact with outer world tells them when to sleep. In those experiments the group adjusted to a 20 hour awake, 10 hour sleep schedule.
      Clearly neither the submarine crew or the 30 hour day people had a problem. What the operators in the article experienced was trying to use a sleeping pattern that didn't correlate with the world around them.
      That means that they probably had problems with sleeping due to light and noise levels they weren't used to. That this causes issues isn't exactly surprising since that has known health impacts and is sometimes used in brainwashing/torture.

    5. Re:So live underground by shadowrat · · Score: 2

      I think the biggest problem would be those on the mars days are here on earth and all the life around them is moving on the regular earth cycle... I can't have lunch at my favorite restaurant, go to the bank, etc... because my days are out of sync. Those people in the Arctic Circle are all on the same clock as businesses and everyone else around them.

      i don't think it's going to be the martian day cycle that keeps the first people on Mars from getting to the bank or their favorite restaurant for lunch.

    6. Re:So live underground by Jane+Q.+Public · · Score: 2

      This is no different that what submariners experience - with no natural light, they move to an 18 hour day (6 on 12 off). Contrast this to driving across the ocean in a ship and traversing the various time zone.

      Also, experiments done decades ago, in caves with no day-night cycle, led to longer awake cycles much like those. So I really don't see what the problem is here.

      Naturally, it takes time to adjust. Shift-work studies have shown that it takes the body AT LEAST 30 days to fully adjust to a new schedule, some people as long as 60. Interrupt it before then and you end up with problems.

    7. Re:So live underground by CycleMan · · Score: 4, Informative

      Interesting. I had read that they adjusted to a 25 hour day, not 30. My source: Richard M. Coleman's book, Wide Awake at 3:00 A.M., page 8, "The results of these sleep-wake cycles shows that most subjects averaged a 25-hour day - that is, left on their own, free from time cues, humans have an internal day length of 25 hours." The problem isn't the Martian day, which is much closer to our natural biorhythms; it is trying to work a Martian time schedule while living on Earth with its time cues.

  2. You get used to it. by Penguinisto · · Score: 5, Interesting

    Seriously - people aren't as fragile as TFA surmises. In the spelunking world, cavers have discovered that after a few weeks without a day/night reference, their circadian cycles stretched out to a 24/24 cycle. In the case of a newly-minted Martian, it won't go that extreme, which means that at least within the timeframe of an exploratory journey, it would be no big deal, and they can adjust between the two on the way there and back (there's plenty of time on the journey to do that.)

    Long term is a bit more difficult to predict, but only in how it affects the body overall. It would certainly adjust and stay adjusted, but I can guess (with no evidence either way) that the effect would be no different than Daylight Savings Time cycles would have on the typical adult here on Earth.

    --
    Quo usque tandem abutere, Nimbus, patientia nostra?
    1. Re:You get used to it. by Trax3001BBS · · Score: 4, Informative

      I can't post (new design) only reply so picked on you :) .

      Ever been to Alaska?

      Walk out of a bar at 4am and it's as bright as noon is very freaky, and your ready to start the day over.

      Noon during the Winter is dark as midnight. Cabin fever is very real in Alaska when one lives far from anyone else (very common), the reason pot was legalized, it gave an alternative to drinking, as alcohol was being abused for relief.

      40 extra minutes of daylight? pffft

    2. Re:You get used to it. by Anonymous Coward · · Score: 5, Interesting

      I agree about people not being as fragile.
      When you deploy on a submarine you go months at a time on an 18 hour day set to GMT. To make it worse there is no light or sun to reference day or night and certainly no reference of weekday or weekend. The only reference you have of what time it is was the type of food being served. Breakfast was always at 6 AM and was traditional breakfast food, lunch at noon was lunch food and so on. The funny thing is with the 18 hour personnel schedule, one day breakfast was your first meal, the next day it was your "lunch" and the third day it was your "dinner".

    3. Re:You get used to it. by DerekLyons · · Score: 2

      When you deploy on a submarine you go months at a time on an 18 hour day set to GMT.

      No you don't. Your watch rotates on an 18 hour cycle, but the boats 'day' (and overall schedule) remains on the standard 24 hour cycle. On top of that, you make the swap from Lima (local time) to Zulu (GMT) once when you leave port and again when you enter port (days, weeks, or months apart) - but someone on Mars time has to deal with the adjustment every day.

      (USS Henry L Stimson, SSBN-655 '83-'87.)

    4. Re:You get used to it. by ZorglubZ · · Score: 2

      I don't get the problem at all; we've had a lunar circadian rhytm for tens of millenia, reset every morning by the sunrise. Adjusting from an internal 25-hour day to an external 24h35m one should, if anything, be easier than adjusting to an external 24h day.

    5. Re:You get used to it. by CrimsonAvenger · · Score: 3, Informative

      No you don't. Your watch rotates on an 18 hour cycle, but the boats 'day' (and overall schedule) remains on the standard 24 hour cycle. On top of that, you make the swap from Lima (local time) to Zulu (GMT) once when you leave port and again when you enter port (days, weeks, or months apart)

      Irrelevant. You roll out of your rack, go to your watchstation for six hours. Then you do PMS/training/whatever for six hours. Then you sleep for six hours. Repeat till you get back in port.

      In other words, you live on an 18-hour day for the period of your patrol.

      As I recall, it took two to five days to adjust at each end of the patrol.

      --

      "I do not agree with what you say, but I will defend to the death your right to say it"
  3. Wrong conclusion by hackertourist · · Score: 5, Insightful

    Living on Mars time is difficult when you're living on Earth and are subject to Earth's day/night cycle.

    Sensory deprivation experiments where people live without clocks and daylight for more than a few days show that people tend to lengthen their "day" to much more than a Mars sol (up to 36 hours IIRC), indicating that adjusting to Mars time is feasible when you're actually on Mars.

    1. Re:Wrong conclusion by Kjella · · Score: 4, Funny

      Living in Norway + artificial light + student life with no real commitments I found that my natural cycle is more like 24/12 = 36 hour days than 24. In fact, without alarm clocks I'd have a helluva time staying on the same page as everyone else. The problem is that that sooner or later that clashes with real life and you must get up in the "middle of the night" for a family dinner or you get up in the "morning" and start drinking at a party which messes you up. On Mars making it another 40 mins would be the least of my worries.

      --
      Live today, because you never know what tomorrow brings
    2. Re:Wrong conclusion by hackertourist · · Score: 2

      Damn you for making me read the entire FA ;-/

      They did do a study that contradicts earlier experiments:

      A person's natural circadian rhythm averages about 24 hours and six minutes for women, and 24 hours and 12 minutes for men. It varies for each individual, but doesn't stray very far from 24 hours. At about the time Pathfinder landed, Czeisler and his team began conducting studies at the hospital's special laboratory that shielded study subjects from all outside influences. With their test subjects in isolation, they simulated the Martian sol to see how the test subjects adjusted to the longer day. "What we learned was none of the people adapted their circadian rhythms to the Martian day," Czeisler said.

      So either earlier studies were off, or Czeisler's experiment was wrong (having e.g. the HVAC on a 24-h cycle, or background noise etc.).

    3. Re:Wrong conclusion by epine · · Score: 4, Insightful

      I have a circadian rhythm disorder. Not long ago I free-ran at 25.5 hours for several years. Advancing by 1.5 hours per day, you're making adjustments to the world around you ever two or three days. Endlessly. I would have mortgaged a minor limb to change my rotational period from 17 days to 21 days. Just to be able to stay in a consistent phase with the day of the week would have been a major blessing.

      I had previously tried melatonin with mixed success. At best, having exhaustively worked through many doses and times, it seemed to reduce my period to 24.25 hours, a little less than 2 hours per week. This is no bed of roses, either. And the melatonin was taking a three hour chunk of out every evening where I was yawning like a date-raped hedgehog waiting impatiently for a fresh coat of paint to dry in his homey bungalow, listless and unable to anything more complicated than cook dinner—usually a fairly simple dinner.

      Recently I tried melatonin again in a sustained-release formulation (newly discovered at retail) and this magically worked much better. At a large dose, I'm able to stay on a 24-hour day permanently, over very close to it. The daily date rape continues to suck.

      At lower doses—minus the daily date rape—I seem to stay near a 24-hour day, with unplanned excursions when it all comes unglued. This might well be addressed by further tweaking. I've ever so close now to having the best of both worlds.

      The operative parameter with circadian rhythm disorder is that there's no such thing as "merely" a flesh wound for a haemophiliac. My clock drifts because there's something broken in the entrainment circuit. A haemophiliac bleeds because there's a gash or puncture or rash, but he continues to bleed because the blood chemistry required for blood clotting is MIA.

      A normal person experiencing severe jet lag (say a trip to Japan or Australia) is in a horrible, unpleasant, barely functional place. In my metaphor, you feel weak because you're gushing blood. In this state, your clotting reflex (if you have a clotting reflex) is actually on overdrive. The stress is horrible, but the body is rapidly adapting and compensating. If you make it through the first day, you hope the second day will suck a little bit less, until after a few days, it hardly sucks at all, then you're body finishes making the adjustment, and everything becomes normal again.

      For a person such as myself trying to maintain a 24-hour day without melatonin, the process goes the other direction. Light jet lag turns in moderate jet lag, and moderate jet lag soon becomes severe jet lag, and severe jet lag soon gives way to waking hypnagogic hallucinations. Every one of my attempts to force myself into adherence with the 24-hour clock on will-power alone developed along this path over two weeks. I was as cognitively impaired at this point as that time I got a bit too carried away in a bout of binge drinking, to an extent I never repeated again. And still the bleeding continued. By this point your will-power is so diminished, you need a jeweller's work bench and a steady hand to make even the smallest life decision. You know you're suffering like hell, but you've almost forgotten what crazy notion drove you to try maintaining a 24-hour waking day.

      From French invasion of Russia:

      The cold was so intense that bivouacking was no longer supportable. Bad luck to those who fell asleep by a campfire! ... One constantly found men who, overcome by the cold, had been forced to drop out and had fallen to the ground, too weak or too numb to stand. ... Once these poor wretches fell asleep they were dead. If they resisted the craving for sleep, another passer-by would help them along a little farther, thus prolonging their agony for a short while, but not saving them, for in this condition the drowsiness engendered by cold is irresistibl

  4. MiB by XanC · · Score: 4, Funny

    The twins keep us on Centaurian time, standard thirty-seven hour day. Give it a few months. You'll get used to it... or you'll have a psychotic episode.

  5. Extra sleep by Anonymous Coward · · Score: 2, Insightful

    40 minutes of extra sleep is hard to adjust to? If we can adjust to seasonal variations in sunlight I think we can adjust to 40 minutes. Admit it, you're doing it wrong.

  6. Uh... by dpidcoe · · Score: 4, Insightful

    These people were trying to adjust to a martian day while still living on earth and seeing the sun still operate on a 24 hour day, so of course they're going to have problems. I'd like to see this tried while keeping the people underground with the lights cycling to actually simulate a martian day.

  7. Sign Me Up by Warhaven · · Score: 5, Insightful

    40 extra minutes of sleep each morning? Yes, please!

    1. Re:Sign Me Up by CptJeanLuc · · Score: 2

      I actually did this (though 2 hours not 40 mins) when studying for an exam. I had gotten myself into a really bad rhythm getting up around noon or so on a regular basis (this was during a period of only exams and no classes), and decided I should reset my biological clock before the exam. However I knew trying to get up early would fail, because I just loved sleeping in too much - even with a 3-alarm-clock system.

      The exam was in 10 days, so I decided to just prolong my day to around 26 hours, which would land me perfectly on exam time - and this is what I did. It was a great experience, I was well rested each "cycle", and during the night it is easy to study with no distractions or interruptions. I had not told the other students living in the dorm about my project, and I remember the priceless look of surprise on one of them as he was getting out from his room at 7 AM in the morning wiping his eyes and coming into kitchen, and the first thing he saw was me taking a lasagne out of the oven (for dinner).

      A Mars day with not even 25 hours? Bring it on ... the only thing better would be if we could find a 26-hour planet.

  8. Let's stay focused, people by puzzled_decoy · · Score: 5, Insightful

    It's not the length of a day that will impact Mars-dwellers the most, it will be their internet speed.

    1. Re:Let's stay focused, people by Miamicanes · · Score: 2

      > It's not the length of a day that will impact Mars-dwellers the most, it will be their internet speed.

      No, it'll be their latency. I believe the scenario informally tossed around by IETF for "extraterrestrial internet" envisions three categories of latency... a relatively small amount of net bandwidth sent directly between Mars and Earth that enjoys the lowest possible latency, and two roughly equal amounts of bulk bandwidth with much longer latencies. handled by satellites at the L3, L4, and L5 Earth-Sun and Mars-Sun Lagrange points. For semi-adhoc websurfing, your request would get sent along the fast (bandwidth-limited) link, and the response would travel along one or both of the lagrange paths. Someone like Akamai would come up with an open web standard that allowed sites to export themselves in their entirety (and remain synchronized in an rsync-like manner) so they'd run in a local VM on Mars.

      Let's use StackOverflow as an example. To kick the whole thing off, SO would take a snapshot of itself (kind of like it already does for archive.org) and begin uploading it to the server on Mars along the high-latency longer lagrangian bulk-data path. Once the server on Mars had a complete copy, it would become their local mirror. Normal bulk updates would occur frequently and periodically along the longest lagrangian path. Posted questions by someone on Mars (and the text of replies to them) might get expedited and sent along the shorter direct route.

      Porn sites and Youtube would do the same thing. If a Martian wanted to visit some smaller site, he'd have to tag them for fetching and wait a few hours for them to become available. They'd probably follow a "Martians Pay" pricing model that split the bandwidth costs among everyone on Mars who accessed specific sites on a regular basis. Popular sites with lots of users (like Reddit and StackOverflow) would be cheap despite having lots of data because the cost would be divided among lots of Martian users. More offbeat sites might force individual users to be somewhat selective and conservative about their bulk-fetches (or at least about keeping them updated in perpetuity if they're only interested in viewing them as a one-shot activity), and might rebate back part of the initial acquisition cost if/when future users go to view the same site (ie, you, the first user, might pay $5 to bulk-grab all the blogger.com postings of {some-user}, but get $2 of it rebated back when/if some future person pays $3, and you'd both get another buck (and further diminishing rebates) as more people paid diminishing prices to gain access to it.

      By the same token, cable networks like HBO and SkyTV would bundle their new video content daily and bulk-upload it to their local affiliate on Mars (who'd make it initially available at some official scheduled time, and thereafter by streaming).

      Ironically, the biggest single limiting factor to bandwidth wouldn't be between Earth and Mars, but between the surface of the Earth and a satellite orbiting the earth in geostationary orbit.Between the L3 and L4 satellites, you can use 30GHz of spectrum if you've got the hardware & power budget to do it. Then double it by sending half the data along the path in the other direction. The problem is the "last mile" between orbit and the surface, where it's likely that something more exotic will be required (say, multiple satellites using tightly-focused lasers to ferry the bulk data between earth and orbit, then bulk-uploading their chunks directly to the lagrangian satellites.

      In short, the future of interplanetary internet can be summed up as multipath, multilink, and Akamai-like CDNs hosting VMs for earth websites on Mars. The biggest hard challenges aren't the technical ones... it'll be dealing with Hollywood lawyers and the copyright mafia losing sleep at night that their precious content is being cached on Mars with insufficient DRM or that someone, somewhere on Mars, is listening to a song that was improperly licensed.

      The resources to maintain this kind of large-scale local cache would be substantial... but probably agreed to without hesitation on the grounds that they'd be likely to make the single biggest difference to morale on Mars than anything not directly related to life-or-death.

  9. I would of thought by rossdee · · Score: 2

    I would of thought that adjusting to the very thin atmosphere with virtually no oxygen would be the biggest problem for humans, then the cold temperatures, and maybe the 1/3 G

    The long days, not so much. But then I work night shift.

  10. DST by stafil · · Score: 5, Insightful

    Let's fix it on Earth fist, and stop fucking with our circadian cycles twice a year!

  11. Solution is already in the works by NEDHead · · Score: 4, Insightful

    When the planet is bombarded with comets as part of the terra forming effort, a judicious selection of impact angles will easily speed the rotation to a nominal 24 hour rate

  12. Re:Heading west two timezones per day? by tysonedwards · · Score: 2

    On Mars, they too are 7 days.

    They instead have 27 months as compared to our 12.

    --
    Thirty four characters live here.
  13. Re:Then why live on mars? by hawguy · · Score: 2

    It's only slightly better than living in a giant spinning space station... or in a bomb shelter right here.

    Be that as it may, humans can tolerate such conditions and there are plenty of volunteers -- look how many people survive for decades in prison, even harsh prisons outside of the USA where they may literally never leave their cell.

    Anything you can do on mars, robots can do better. already.

    Then why did it take a big team of human workers to build my house? Surely a robot can hammer a nail into a piece of wood?

    Why do we send human firefighters into a burning building? Why are we risking human lives for this if robots can do it better?

    Why does an industrial plant call in a human technician to repair their broken robots, why don't they just call in a robot to fix the robot?

    Special purpose science robots can do a lot, but there is still no robot that's as versatile as a human. The mars rover is a great example of a robot performing great science (that's far exceeded expectations), but try asking it to step over a 2 foot high wall to reach an interesting object, or asking it to excavate a 3 foot deep hole to see if someone buried an obelisk there.

  14. I had rocket lag all rocket summer. by uCallHimDrJ0NES · · Score: 2

    But I found my hometown waiting for me on Mars, so I just slept it off in my old room from when I was a kid.

    --
    Cloudiot: A person who does not see offsite storage as a way to lose control over access to his or her own data.
  15. 40 min? How about 4 hours extra per day? by trumpetplayer · · Score: 2

    Yet some people actually choose to have 28 hour long days, i.e. 6 day long weeks: http://www.explainxkcd.com/wik...