Time Keeping for Aliens

Loren

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Well, when world building an alien society how would you go about segmenting time and seasons of the year?

That was and still is a challenge I am wrestling with.

I think we we all understand the calendar and its history well enough. It all started with the advent of agriculture and a means to track growing and harvesting seasons on a yearly cycle.

The year was further subdivided by the lunar period, or at least guided by it, but that had it's share of difficulties, so eventually a dynamic length month was selected. There were a number of revisions to this plan and there are still efforts by some groups to modernize the Gregorian calendar.

Many of the problems are attributed to the orbital period of the Earth. Earth does not orbit the sun at an integer number of days. It takes 365.256 sidereal days to complete a full orbit, so we opted for leap years to periodically readjust our calendars to prevent drift with respect to the true seasons.

I'll digress momentarily to address sone vocabulary. When we talk about a fun day we think in terms of 24 hours with high noon at the same point in the sky (ignoring seasonal tilt). That actually is slightly more than a full revolution of the earth because we are orbiting our sun. Consider placing an object at the center of a room and drawing a large circle around it. If you stand facing that object on the circle then repeat the same thing, but move along the perimeter of the circle 90° you are still facing the object, but you are not facing the same direction with respect to the walls of the room.

Sidereal time is based on your orientation to the room, not the object. Or, in the actual world, it is based on the Earth's orientation with respect to other stars. Okay, let's get back to business.

We can design an alien planet's calendar based on the same principles we designed ours. That seems pretty clear and believable, but what about the hours and minutes?

That's where things get screwy. Have you ever wondered why 12 and 60 is used for delineation of the Earth day? Well, 12 probably came about due to the position of some key stars. At first we only cared about daylight hours and the sundial became our first clock. Not that an hour was not always the same length due to seasonal changes and the amount of daylight in a day. It wasn't until the invention of the mechanical clock that the hour was standardized. I'll buy that.

For us Pentadactyl apes, base ten rules because of the number of digits on our hands and feet. So, we use 1, 10, 100, 1000, fluently. But why 60 minutes in an hour?

My first thought was a smart alien society would simply use the base that they counted in. I am assuming that they are smart, perhaps smarter than we are. Let's say they also use base-10 for simplicity's sake. Where did 60 come from?

Well, it turns out that there may have been some logic to the number 60 after all. Remember that no one had calculators thousands of years ago, so ancient time engineers may have made something that was easy to manage. It turns out that 60 is an easy number to reckon with.

60 is easily divided by 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, and 30. That's not only convenient for time, but it seems that ancient mathematicians also found it simple for geometry. With a little help from our lunar cycle and the period of the year, 360 seems to have been a worthy compromise for the number of degrees in a full circle. Again, 60 divides into 360 nicely, eliminating those pesky decimals and fractions we all hated in grade school.

Much of this is what I call strong conjecture, but the evidence I have found in my research seems pretty compelling.

So, my quest to world build a logical time system for my alien societies has taken on a new twist. What appears to have been arbitrary divisions for time by humans seems to have its roots grounded in solid logic.

I would be interested in hearing other opinions on developing time counting schemes for other worlds. Using Earth hours and minutes by an alien race to describe events or actions would be a little silly. For instance, I suspect that a dinner date for another race wouldn't ask to be picked up at 8 O'Clock. :)

What do you think?
 
Not alien, but even on Earth there have been some interesting calendrical systems, e.g. The Mayan Calendar - an explanation

So maybe the aliens could have different calendars for different purposes, e.g. ritual as with the Maya, and these all interact?
 
12 and 60 is used for delineation of the Earth day? Well, 12 probably came about due to the position of some key stars.
20 is also important, it might be 16 (four limbs with 4) or 18 (2 x 5 and 2 x4) or 32 (6 x 4).

59 in Mayan is literally translated three men less one and 20 is one man. They counted the toes as well as fingers.
Celts, Aztecs the only other well known cultures that counted in 20s as Mayans did.

Even today, knuckle joint counting still exists.

There are good reasons why an alien would have bilateral symmetry and four limbs rather than six. Kangaroos and some other creatures with tails have effectively a fifth limb, unlikely to have "digits". Aliens might be warm blooded egg layers, monotreme like (only two now exist here), marsupial like or mammal like, Octopus /Squid like (six, 8, 10 tentacles) or like Coconut crab (likely 6 or 8). That might cover every more likely eventuality. Copper (or similar non-iron) based blood rather than iron if it's very cold or high pressure.
Read From One to Zero, or the newer three volume History of numbers by Georges Ifrah. It shows which aspects are related to culture, biology and are inherently mathematical.
Best resource ever for numbers / mathematics of Alien Worlds.

Computers of the Turing Machine kind, rather than Analogue are MOST SIMPLY implemented using base 2 (Binary, true / false, the 1 and 0 are just human symbols for the irreducible mathematical concept). Octal and Hexadecimal are then natural bases for any alien programmer as binary is very unwieldy if you are not made of clock work & cogs, relays, transistors or valves (tubes). All of which are very obvious technologies to make a turning machine type computer, which is the simplest mathematical concept (not human) for a programmable computer.
 
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20 is also important, it might be 16 (four limbs with 4) or 18 (2 x 5 and 2 x4) or 32 (6 x 4).

59 in Mayan is literally translated three men less one and 20 is one man. They counted the toes as well as fingers.
Celts, Aztecs the only other well known cultures that counted in 20s as Mayans did.

Even today, knuckle joint counting still exists.

There are good reasons why an alien would have bilateral symmetry and four limbs rather than six. Kangaroos and some other creatures with tails have effectively a fifth limb, unlikely to have "digits". Aliens might be warm blooded egg layers, monotreme like (only two now exist here), marsupial like or mammal like, Octopus /Squid like (six, 8, 10 tentacles) or like Coconut crab (likely 6 or 8). That might cover every more likely eventuality. Copper (or similar non-iron) based blood rather than iron if it's very cold or high pressure.
Read From One to Zero, or the newer three volume History of numbers by Georges Ifrah. It shows which aspects are related to culture, biology and are inherently mathematical.
Best resource ever for numbers / mathematics of Alien Worlds.

Just found it on Amazon and bought it. Thanks for the tip!
 
Which version? (I have both!)

The History of Numbers.

Thanks for the additional information on computers. This society I am writing about is already at the qubits stage. :) But I need to flesh out a calendar and time format for the society.

They are also humanoid (10 toes and fingers). Planet is Earth-like, .934 Earth Masses, with a year that is 300.9 solar days and a day that is 24.79 Earth hours long. Nothing too exotic.

Incidentally, for those that want to do some hard sic-fi world building, this planet designer website might be of some interest. He even provides the source equations for his online calculators for those of us that like math gymnastics. :)
 
This society I am writing about is already at the qubits stage.
Quantum computers using qubits are not general purpose turing machines. They only easily solve particular problems. Forever, a binary based computer is mathematically provable to be the most reliable implementation of general purpose computing. It's based on logic, set theory, mathematics, not technology or human-centric ideas or culture.

Read this if you haven't! A Qubit resolves to a bit (true OR false), but during "operation" has "True AND False" superimposed! With super dense coding, you MIGHT count in base 4 (0,1,2 3) or using two Qubits in base 16 (=Hexadecimal, human representation is 0 ... 9, A, B, C, D, E, F). However that's unlikely. More likely is that a Quantum Computer using Qubits would be a coprocessor to a classical binary CPU (just as FPUs and GPUs are today). A regular binary computer can be made with IDENTICAL architecture and operation (but not speeds) using relays, valve (tubes), transistors (ICs) or even using mechanical or biological parts that can be specified in the interconnection and interaction by Boolean Algebra.

You can get a cheap clone of old Sharp calculator that has Decimal / Octal / Binary / Hex modes. My human characters use them on the alien's planet as otherwise a taxi fare sounds a lot larger than it really is (my aliens have 3 fingers and thumb and 4 toes so count in Octal naturally, this means their computer programmers don't use hexadecimal).
 
They are also humanoid (10 toes and fingers). Planet is Earth-like, .934 Earth Masses, with a year that is 300.9 solar days and a day that is 24.79 Earth hours long. Nothing too exotic.
Has it a moon (or two)? Without a moon, they won't bother with months (the word even means moons)
a twenty hour day might be likely.
A Fortnight is from Fourteen Nights. Days can be from Midnight (Roman), dawn or dusk (Jewish and pre-Roman Celtic)
They might have a 301 day year and drop a day every 10th year.
Seasons can be from axial tilt OR a markedly elliptical orbit or both. That naturally divides the year in four*. They might have thus 75 days per quarter and add the missing 0.9 as full day 9 years in 10.

Various societies here have used 7, 8 and 10 day weeks.

[* One series I've written, the aliens divide the year to seven seasons, for mystical reasons. The Solstices and Equinoxes fit a little awkwardly. They have a moon and 14 months that badly fit the solar year, so they have extra days at Solstices and Equinoxes that are not part of a named month. Really you are only limited by your own imagination. People done all sorts of mad stuff in real life, though usually there is a plausible explanation, so it only needs to make sense to the aliens. Like old UK 12 pence & twenty shillings or USA 2 bits (actually a quarter doubloon, hence also "pieces of eight") the real origin of something can be 100s or 1000s of years in your alien's past ]
 
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Has it a moon (or two)? Without a moon, they won't bother with months (the word even means moons)
a twenty hour day might be likely.
A Fortnight is from Fourteen Nights. Days can be from Midnight (Roman), dawn or dusk (Jewish and pre-Roman Celtic)
They might have a 301 day year and drop a day every 10th year.
Seasons can be from axial tilt OR a markedly elliptical orbit or both. That naturally divides the year in four*. They might have thus 75 days per quarter and add the missing 0.9 as full day 9 years in 10.

Various societies here have used 7, 8 and 10 day weeks.

[* One series I've written, the aliens divide the year to seven seasons, for mystical reasons. The Solstices and Equinoxes fit a little awkwardly. They have a moon and 14 months that badly fit the solar year, so they have extra days at Solstices and Equinoxes that are not part of a named month. Really you are only limited by your own imagination. People done all sorts of mad stuff in real life, though usually there is a plausible explanation, so it only needs to make sense to the aliens. Like old UK 12 pence & twenty shillings or USA 2 bits (actually a quarter doubloon, hence also "pieces of eight") the real origin of something can be 100s or 1000s of years in your alien's past ]

Yes.

Radius 1539 km
Mass = 5.9834E 22 kg (0.81 Lunar Masses)
Orbital Radius = 310,000 km
Orbital Period 20.3 Days
Orbital Inclination 4.7°
Apparent Angular size = .57°

I think I will be doing some changes as the tidal forces are 1.74 times greater than Earth.
 
I much prefer the old HP-16C. I also have a number of HP-11C scientific calculators that I regularly use.
 
I much prefer the old HP-16C. I also have a number of HP-11C scientific calculators that I regularly use.
nice if you have it!

OK you can have good fun having 3 to 5 calendars of different past times and cultures of your aliens, with their current one that cleverly combines the moon's (months) with sun (year) and seasons for an adapted "proper" calendar. Also likely an extra day added or dropped occasionally as the year won't be EXACTLY 300.9 (drop one day every ten years).

You can see how Gaulish 13 months was adapted to fix moon /sun and the 3 roman ones pre Julian, Julian and Gregorian. Also how current Jewish calendar cleverly syncs months/seasons/festivals with Solar year (the Muslim one is purely lunar, so their festivals rotate through the entire year). See how the Chinese and Mayan ones work (all on Wikipedia) This will give you inspiration as to how aliens might devise a Calendar and refine it over 3000 years and in different ethnic groups they might have.

Then you have the fun with historical Alien dates. Which calendar was in use? UK and Sweden got terribly out of sync with rest of Europe as they stayed on Julian long after everyone else adopted Gregorian calendar. Again, you can look this up in Wikipedia and it's quite amazing.

Have fun. :)
 
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I bought the 16C and 11C a long time ago. However, there is an interesting story that equals those old workhorses.

A few years ago I asked my girlfriend for another 11C for Christmas as mine was getting a bit worn. She found me a nice one with a case, which is being used right now.

Shortly after that a childhood friend's dad died. His dad was a mentor to me in a way and my friend gifted his 11C to me, which I took with great honor.

His dad invented a very early computer that solved mazes in the late 1950s for the Franklin Institute in Philadelphia. I was also gifted his original yellowing manuscript of that design, which is tucked away on a shelf near my computer.
 
Based on the potential mathematical coincidence behind seconds and minutes I'd almost guess that it could be probable that an alien year and day might vary largely based on the orbit of the planet and it's rotation; but there could be a closer relationship with minutes and seconds. The reason I say this is that if their world is spherical like ours there is a higher probability that through coincidence and what you state about a Sexagesimal (base 60) system they could find that as a convienient means of marking their time in minutes and seconds and also mapping their world in minutes and seconds; though they don't need to call them that.
 
Based on the potential mathematical coincidence behind seconds and minutes I'd almost guess that it could be probable that an alien year and day might vary largely based on the orbit of the planet and it's rotation; but there could be a closer relationship with minutes and seconds. The reason I say this is that if their world is spherical like ours there is a higher probability that through coincidence and what you state about a Sexagesimal (base 60) system they could find that as a convienient means of marking their time in minutes and seconds and also mapping their world in minutes and seconds; though they don't need to call them that.

True. I was hoping to differentiate it enough that is didn't seem like I was "cheaping out" and just using the SI units we use.

Of course, I could always add a little blurb "showing" why.
 
360 degrees for a circle, 60 minutes = degree, 60 seconds = minute
It's easy to count to 12 on one hand (Ancient Egyptians as well as Pakistan, India, Indochina, Afghanistan, Iran, Turkey, Iraq and Syria, others counted to 27 or 28 on a pair of hands)

60 isn't natural like 5, 10, 12 and 20 is (using fingers, toes, joints etc). The only known reasons are mathematical. No-one actually knows why the the system was introduced. But it's such a large number base that the Ancient Sumerians added base 10 to it for convenience (Georges Ifrah).
Ancient Sumerians, Babylonians, Greeks and Egyptians used base 60 and we still do for lat & long, angles and time.

60 has the first six whole numbers as factors.
 
Sounds an interesting problem.
To take the idea of developing time systems further, what happens if they become multi-planet based, as we may be soon?
Also, would they keep the same time units on their ships if they were space-faring? How about on space-stations, or habitats?
One size would not fit all, perhaps they would develop a 'Standard Time' & then have various 'Local Times' for the different locations?
How time would be quantified in a multi-species environment, how it would be regulated/shared between & amongst the different alien sectors of space & further, in a Galactic-wide environment..?
.. I'm getting a headache.
 

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