320: 28-Hour Day

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28-Hour Day
Small print: this schedule will eventually drive one stark raving mad.
Title text: Small print: this schedule will eventually drive one stark raving mad.


The 28-Hour Day is a modified sleep schedule proposed to accommodate the discrepancy between the earth's day-night cycle and certain people's preferred sleep schedules. It discards the traditional notion of sleeping at night and replaces it with sleeping when it is more convenient for weekend parties and mid-week insomnia. It is one of the alternative day lengths that will sync with the widely accepted and practiced 168-hour week (168 = 7×24 = 6×28), with another option being eight 21-hour days. Underneath the weekly timeline, Cueball describes the schedule's selling points to his friend, who apparently has difficulty sleeping.

Cueball's friend shows little interest in this idea, and instead he resorts to low-quality "your mom" jokes. Cueball merely bides his time, and in the end successfully trumps the jokes with a response that impugns his friend's sexual stamina, leading him to concede defeat.

The title-text uses "Small print" to mean "Disclaimer" and relieves the idea's creator of any responsibility in the case that it is tried and the tester finds the schedule to be a really bad idea. As he states, if you live by this schedule, chances are you will be driven stark raving mad. Given that Cueball gives his friend with the bad mom jokes this advice, it could be another way to try to punish him for the jokes. Although Randall makes several Your Mom comics, he has also in some comics shown that he dislikes these kind of jokes, especially when used too much in real life (see 366: Your Mom.)



[Above the panels of the main comic, there is a ruler-like time line diagram that shows the hours in a week. It has 6 black sections labeled "bed" in white text, at the top and 7 black sections labeled "night" in white text, at the bottom (the first and last sections are split in two as it goes from the end of the week to the start of the (next) week. So there are 8 night sections, but they only cover 7 times 12 hours). The night sections always go from 6PM to 6AM. But the bed sections are only 8 hours long and they only stay fully over the night sections two times, and two times they are not above the night sections at all. Above the ruler, the bed times are shown. These labels are over the relevant ticks on the ruler. The ruler has small ticks for every two hours, longer ticks at noon, and a line that goes all the way through the ruler dividing each day. The ruler begins on midnight as Sunday starts and ends as Saturday finishes at midnight. Below the ruler each day are labels with the three-letter abbreviations in a much larger font. Here below the rulers, text is transcribed with the day first, then night or bed according to which comes first, and the time interval for bed given after each bed. The first and last night will only be a partial word and only the first time will there be a (ni)ght to start.]
10AM 6PM
2PM 10PM
10PM 6AM
2AM 10AM
[Below the ruler are five panels. In the first, two Cueball-like guys are talking together. Cueball is addressing his friend with one hand raised.]
Cueball: You have trouble sleeping right?
Friend: Only when your mom is over.
[Cueball is now standing next to a an easel with a large version of the chart shown above the panels. Cueball is pointing to the chart while his friend is looking at it.]
Cueball: Since your work is flexible-
Friend: -Like your mom-
Cueball: -you should try the 28-hour day - 20 awake, 8 asleep (or 19/9 if you prefer).
Friend: I prefer your mom.
[Cueball moves forward toward his friend, with the chart behind him. He holds both hands, held together, up in front of him. The easel with the chart can now be seen to have three legs, as opposed to only two shown in the previous panel.]
Cueball: It synchs up with the week - you spend weekdays awake normally, then on weekends you can go out all night.
Friend: Just like your mom.
[In a frameless panel, only Cueball is shown from the torso up. He gestures with both arms raised on each side of him.]
Cueball: It means four extra hours daily. You can stay up until you're exhausted every day and then spend a full 9 hours asleep each night!
[Back to both again, but without the chart. Cueball leans toward his friend as his friend lifts a hand to his chin.]
Friend: But how much time can I spend doing your mom?
Cueball: You? I'm guessing three or four minutes, tops.
Friend: ...Well played.


For a system with an integer number of hours in an integer number of days (thus not invoking fractions while keeping both the basic hour and the week consistent with current usage), you could distribute each of the prime factors of both 24 and 7 (i.e. 2, 2, 2, 3 and 7) to either the baseline "hours in a day" or "days in a week" value to produce a 'valid' week-synchronous scheme in sixteen unique combinations: [zero to three '2's] × [zero or one '3's] × [zero or one '7's] factored into the value of one, and all remaining options applied to the other. This includes the extreme possibilities of a single '168-hour day' or 168 'one-hour days'.

Aside from the usual 24×7 itself, 21×8 and 28×6 are the closest possible distributions to our habitual circadian rhythms and some research indicates that daylight-active creatures (such as ourselves) can adapt more to periods slightly longer than 24 hours better than those that are correspondingly shorter, especially with compatible cycles of light. Whether any such plan is sustainable may be another matter.

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Some time ago I've written a tool to set your personal 28h day schedule: http://28h.t-animal.de Give it a try :) 00:19, 21 August 2013 (UTC)

Can the tool be used on your mom? 23:40, 10 October 2013 (UTC)
Pretty neat tool, nice job! :) --Waldir (talk) 16:17, 23 November 2013 (UTC)

Uncanny, I've actually been up since 3am, today (Wednesday... at least I think it's Wednesday), which closely matches this comic that I've just coincidentally passed through while browsing. Of course the reasons for this are different (it's too hot, and my seasonal hay-fever isn't helping me sleep either, and it's just crept over 17 hours of daylight, at this latitude).

And I can additionally attest from some (also unrelated) experiments in personal day-lengthening, several years back, that doing this long-term can cause noticable problems, even when planning several days ahead to ensure you synch up (or at least mesh compatibly) with various forthcoming appointments and commitments. 16:47, 19 June 2013 (UTC)

Problems with appointments or problems with health? I don't want to try this and end up going stark raving mad. 11:11, 12 June 2014 (UTC)

I removed the Incomplete tag. I don't really see how this explanation could go much further, apart from citing some semi-reputable sources confirming that the 28-hour day is not just one of Randall's thought experiments. It is notable enough for many things, but unfortunately not its own Wikipedia article, so background checks need to be done. Maybe I should put that Incomplete tag back, in retrospect... --Quicksilver (talk) 20:01, 21 August 2013 (UTC)

So then please add a trivia explaining the people from JPL working for MSL. If you do not understand you can ask me. --Dgbrt (talk) 22:02, 21 August 2013 (UTC)

I think an important aspect of day-lengthening deserves highlighting: that you get more waking hours per week, but can still sleep a full 8 hours at a time. 17:46, 23 December 2013 (UTC)

Hello. I found this article looking for "28 hour day" because I live in this way although I sometimes stay awake longer than 20 hours. I am 47 and have been like this for about 20 years. I work my own hours and do not have children, therefore never had to abide by any 24hr schedule. I never had a body clock and I prefer to sleep during daylight hours although the day / night schedule does not affect my sleep pattern. The numbers of hours I sleep ranges from 5 to 8. I sleep less if I eat too many processed carbs (ie.sugar) or when it's hot in summer. I sleep more when it's cold. Exercise has no effect. I live in Ibiza, Spain. Thanks

I just tried the sleep schedule for one week. If you are interested in it, I shared my experiences and tips in the following blog post: https://return2.net/field-report-testing-28-hour-day-sleep-model/ -- 22:50, 27. April 2021 (UTC)

I've tried this and it did indeed make me stark raving mad. Even if you get enough total sleep you still behave as if you're tired for a large portion of the day, typically around when you would have been waking up with your normal schedule. Coffe can work sometimes, but drinking coffee is dangerous because it can mess with your sleep schedule and this sleep schedule is pretty brittle. Would not recommend unless people around you won't notice you speaking oddly in the mornings. 10:10, 16 May 2021 (UTC)

I have also tried this since I seem to gravitate towards it anyway. In my case though, I loved it! Better rested, more alert, etc. 13:39, 4 March 2024 (UTC)