Kepler Calendar Design

[caters]

Here is how I designed the time system for Kepler Bb, a fictional planet of mine.

I took the number of days in an earth year and then started to extend each of these measurements:
Year
Day
Hour
Minute

I ended up with 1313 Kepler days being equal to 3112 earth days. That is 8.5 earth years per Kepler year. Each day is 32 hours long, each hour is 80 minutes long, and each minute is 80 seconds long. The second has been kept the same for physics purposes.

Now I calculated that since there are 4 seasons and 4 transition phases and each season is 3 months long and each transition phase is 2 months long that I need 20 months in the year. And I need to spread 1313 days across those 20 months. If you think that designing the Gregorian calendar was hard in ancient times, this is harder, not because I don't know the orbital period of the planet and all its seasons and transition phases but because it is me designing this.

As for what the months will be based on, I have no clue. Moon cycles would be too complicated and not enough of them would fit in a year since Kepler Bb has 4 moons in resonant orbits for stability. This means that potentially a solar eclipse and a lunar eclipse could both be seen from the same place at the same time and the likelihood of eclipses in general is higher. But eclipses would also be too complicated and would only line up every x years(x here is large).

Here are the seasons and transition phases:

Spring, flowers start blooming everywhere, cool to warm
Sprummer, Spring flowers are at the peak of their bloom, starts getting hot
Summer, Hot, lots of fruits and vegetables at this time
Summer Fall, Still hot but starts cooling down, Fruit and Vegetable yield drastically decreased, Trees start changing color slightly
Fall, Beautiful, multicolor forests, cool to warm
Fallter, Trees drop their last few leaves and any seeds that stayed on, starts getting cold
Winter, Cold and snowy, Everybody stays underground but only a minority hibernate
Winter Spring, Still cold but starts warming up, plants that will bloom in spring start growing

Sprummer, Summer Fall, Fallter, and Winter Spring are those transition phases I am talking about.

Each one of these 4 has 2 months instead of 3.

I am sure I can come up with a year designation system, month names, and day names but the calendar itself is where I am stuck. How many days should I have per month(Maybe you could put it in Kepler days so that it is easier than earth day to Kepler day conversion)? How many weeks per month? How many days per week?

I am asking because once there is a civilization, people will want to know things like "When does spring start? When is this summer holiday? etc.".

I know it is all up to me but could you at least give me some ideas as to where to find the information I need if any and how to go about this big process? I am using spreadsheets to keep track of all the months. Right now I am just numbering them.

 

[Brian G Turner]

When does spring start?

It sounds as though you're trying to draw up a calendar with no idea what a calendar actually is, so I'd recommend starting here to begin learning your topic:
Calendar - Wikipedia, the free encyclopedia

 

[caters]

I know what a calendar is. It is a way to organize a year into months in an easy to understand way. What I don't know is the number of days I should have per month, per week, weeks per month, or how I should spread those days.

I don't even know what to base the month off of since all the things I can think of are either too complicated(lunar orbit resonance with 4 moons) or too unreliable(eclipses, temperature change, etc.)

But I do know what a calendar is.

Eclipses could be reliable for civilization eras and ages but not for months of a year. Temperature change would only be reliable if it was constant or at least periodical. But it never is. Even the places with the least temperature change(places at the equator) still have quite a bit of temperature change and the direction and degree of temperature change is unpredictable.

 

[Brian G Turner]

I know what a calendar is. It is a way to organize a year into months in an easy to understand way. What I don't know is the number of days I should have per month, per week, weeks per month, or how I should spread those days.

And that's exactly my point - read about the history of calendars and how they have been developed by civilisations on earth. There are different forms according to different needs and belief systems. If you can account for that then you can begin to properly structure your calendar.

 

[caters]

How is that going to help? I mean this calendar is for a fictional planet so who knows haw many days each month has or how many days per week there are or how many weeks each month has?

But I need to know if I am to get any further in my story(I have reached the end of the family level chapters and next up is civilization level chapters).

 

[The Judge]

I think perhaps you're missing the point of Brian's comments.

At present you are the god of your creation and you are imposing on it a system of expressing the passing of time. This is perfectly valid and exactly what I've done with my SFs and fantasies. In my latest WiP I wanted one holy day a week -- ie the equivalent of a Sabbath or Sunday -- and I needed two holy days within a specific period, giving me a week of 8 days, since 7 was too short for the journey they were undertaking, and 9 meant a day when nothing happened. The characters all then work within the constraints I impose on them.

What (as I understand it) Brian is encouraging you to consider is to make the process a bottom-up creation, not a top-down one, so that it is the ancient peoples in your world who devised the various calendars, whether to help agriculture by setting down when seeds should be planted or animals killed, or by way of honouring their gods or whatever -- ie taking the nature-inspired seasons you have created and carrying that on a little further.

However, while the division into days, lunar months and years can be based on natural phenomena, the division into weeks and calendar months is -- on Earth, anyway -- a purely man-made construct. So either let your ancient characters find a way of regulating those -- the holy animal of one influential religious sect had 6 legs or lived for only 45 days, or an autocratic ruler once decided he liked the numbers 4, 17 and 58 -- or just pick some numbers and use them, which is all the first option is in truth, save it's dressed up in world-building clothes. Really, it's not rocket science here.


By the way, I imagine the "When is this summer holiday?" as an urgent question raised at the dawn of civilisation was said very much tongue-in-cheek. If not, then frankly you have more problems than merely working out how many days there are in a week.

 

[caters]

I think perhaps you're missing the point of Brian's comments.

At present you are the god of your creation and you are imposing on it a system of expressing the passing of time. This is perfectly valid and exactly what I've done with my SFs and fantasies. In my latest WiP I wanted one holy day a week -- ie the equivalent of a Sabbath or Sunday -- and I needed two holy days within a specific period, giving me a week of 8 days, since 7 was too short for the journey they were undertaking, and 9 meant a day when nothing happened. The characters all then work within the constraints I impose on them.

What (as I understand it) Brian is encouraging you to consider is to make the process a bottom-up creation, not a top-down one, so that it is the ancient peoples in your world who devised the various calendars, whether to help agriculture by setting down when seeds should be planted or animals killed, or by way of honouring their gods or whatever -- ie taking the nature-inspired seasons you have created and carrying that on a little further.

However, while the division into days, lunar months and years can be based on natural phenomena, the division into weeks and calendar months is -- on Earth, anyway -- a purely man-made construct. So either let your ancient characters find a way of regulating those -- the holy animal of one influential religious sect had 6 legs or lived for only 45 days, or an autocratic ruler once decided he liked the numbers 4, 17 and 58 -- or just pick some numbers and use them, which is all the first option is in truth, save it's dressed up in world-building clothes. Really, it's not rocket science here.


By the way, I imagine the "When is this summer holiday?" as an urgent question raised at the dawn of civilisation was said very much tongue-in-cheek. If not, then frankly you have more problems than merely working out how many days there are in a week.

You sure the month is purely manmade here on Earth? As far as I understand it is based on lunar cycles and the changes were made so that 365 days were divided into an easy number, 12 instead of 13 if it was based on just the moon alone. But this lunar cycle month becomes too complicated when you have multiple moons because you don't know if you should use the moon closest to the planet, the moon furthest away from the planet, or some other moon or an average of all the moons, or possibly a planet.

Solar gets complicated when there is more than 1 star in the system. The only thing about a solar calendar that never gets more complicated is day/night cycles.

Both of these things are true in the solar system Kepler Bb is in. Kepler Bb has multiple moons and the star system the planets orbit around is a close double binary(so 4 stars that are close and in binary pairs). So either of these(lunar or solar) wouldn't do. 1 person gave me an idea that maybe I could simply divide 1313 days in a year by 20 months in a year and whatever the remainder is is what I have to spread across the months unevenly. That would be a start since then I only have the weeks in a month and days in a week to figure out.

 

[Biskit]

I'm afraid you really are missing the point completely.

The second has been kept the same for physics purposes.

Physics doesn't care how long a second is. It's probably convenient from a story-telling perspective, if you are going to refer to things at the 'seconds' level, but the second is just a measure of time. Just like inches and centimeters are measures of distance, and physics works just fine with either.

I know what a calendar is. It is a way to organize a year into months in an easy to understand way.

Definitely missing the point. These days a calendar would probably be designed by a committee, but real calendars evolved to keep track of stuff - when to plant, when to harvest, when to sacrifice a few oxen to the gods.

You sure the month is purely manmade here on Earth?

It's all manmade.

A lot of it is seriously arbitrary. Yes, ancient civilisations used lunar cycles. Subsequently it turned out that lunar cycles are not in a simple integer ratio with the Earth's orbit around the sun, so some fiddling had to happen. Then it turns out that the Earth's rotation period does not have a simple integer ratio with the Earth's orbit around the sun, so yet more fiddling and the creation of leap years to straighten it out.

If you don't understand the basics of how calendars evolved, you are going to struggle.

 

[The Judge]

You sure the month is purely manmade here on Earth? As far as I understand it is based on lunar cycles and the changes were made so that 365 days were divided into an easy number, 12 instead of 13 if it was based on just the moon alone.

Um... I did make the difference between the lunar and calendar month. At some point people have sat down and said "This lunar thing isn't working, we need something better" and have then changed it, and tinkered around with the change, robbing days off one month and shoving them on another for whatever reason (probably hubris and/or flattery in the case of July and Julius Caesar). In my language, that equates to being man-made.

In any event, you're missing the point I've made. You're the one who has imposed this complexity of moons and suns on your planet's inhabitants, so just carry on and impose a calendar on them. You've already arbitrarily decided how long a minute, hour, day and year all are, so just pick a damn number for the number of months in a year, and for the days in a week and month and use it.

If you want some kind of rationale for the number of months etc, then as Brian has suggested you need to think about the people who would live on this planet, which, to be frank, is certainly not apparent in your posts to date. They might have multiple moons orbiting above them, but over millennia different groups would likely have favoured different moons for one reason or another, or perhaps have favoured them all in different ways -- eg moon 1 might regulate agriculture as she is the goddess of corn, moon 2 as the largest would be used for the religious calendar, and so on. There are also star-calendars -- when does the constellation of the Great Warfish appear in the night sky, or the Anchor drop below the horizon?


With respect, there is absolutely no need to keep telling us about the vagaries of your cosmos. It's intricate. We get it. Your choices now are to try and live your world as its ancient peoples would have done, or just pluck figures out of mid-air, like the 20 months in a year. Either way, there's not a lot more anyone can help you with, You're the one who has to make the decision, so I suggest you just do it.

 

[Brian G Turner]

You sure the month is purely manmade here on Earth? As far as I understand it is based on lunar cycles

This is why I suggested you read up about calendars - lunar cycles has nothing to do with months as measured in a solar calendar, though there are lunar calendars where they obviously may.

 

[caters]

If the second changed length, everything would change from the speed of light to the orbital period of planets, to the length of a day, and anything time related. So yeah, physics does care how long a second is.

 

[Biskit]

If the second changed length, everything would change from the speed of light to the orbital period of planets, to the length of a day, and anything time related. So yeah, physics does care how long a second is.

The second is an arbitrary choice of unit. Change the length of the second and the numerical value of the speed of light will change, the actual speed will not. I think you need to go and talk to someone who understands physics.

Biskit, aka Mark Huntley-James, BSc, PhD (Physics)

 

[Steven Sorrels]

The second is simply a measurement based on atomic rotations. It is in fact arbitrary, and so (while I understand your desire to maintain the second) it's all arbitrary. Here's a link explaining.

Second - Wikipedia, the free encyclopedia

I think maybe you are picking the wrong battles. The length of an hour only matters in reference to a different time scale, and even then only mildly. Don't get hung up on the details, or else try to simplify. You may be making things more complex than they need to be.

 

[dask]

If the second changed length...

The second is an arbitrary choice of unit. Change the length of the second and the numerical value of the speed of light will change, the actual speed will not.

If you're in a space ship approaching the speed of light, doesn't time (and therefore its component parts such as the second) actually slow down (change length) even though the speed of light remains constant? (Not a physicist by the way, that's why I'm asking.)

 

[Steven Sorrels]

If you're in a space ship approaching the speed of light, doesn't time (and therefore its component parts such as the second) actually slow down (change length) even though the speed of light remains constant? (Not a physicist by the way, that's why I'm asking.)

For the person in the ship, it does slow in relation to outside time. The passage of time, regardless of how you measure it, continues at the same pace under normal circumstances, however.

 

[Toby Frost]

Going off on a tangent, is this for a novel? I ask because I'm not sure why it's very important unless the way that time is measured is central to the story. In Nightfall, Isaac Asimov said that he referred to the vehicles on an alien planet as "cars" because it was easier to read that way, even if they were slightly different to cars on Earth. If it isn't especially important to the story, I'd just be a bit wary of letting the world-building run amok, to so speak.

 

[caters]

There is a definition of the second based on the speed of light itself(the standard SI measurement of second). Sure seconds as a time unit might have come from circles and the Babylonians' base 60 but as a standard unit of measure, it came from the speed of light when the people who designed the SI system redefined all units except the kilogram based on things more universal(such as the speed of light).

Based on this speed of light definition of a second and the fact that anything in physics can't go faster than the speed of light(even matter in a black hole doesn't go any faster than light does), if the second changes so does the speed of light and the speed of light can only be different in a separate universe with different physics than ours.

 

[Steven Sorrels]

There is a definition of the second based on the speed of light itself(the standard SI measurement of second). Sure seconds as a time unit might have come from circles and the Babylonians' base 60 but as a standard unit of measure, it came from the speed of light when the people who designed the SI system redefined all units except the kilogram based on things more universal(such as the speed of light).

Based on this speed of light definition of a second and the fact that anything in physics can't go faster than the speed of light(even matter in a black hole doesn't go any faster than light does), if the second changes so does the speed of light and the speed of light can only be different in a separate universe with different physics than ours.

Technically, the speed of light would still remain the same, just the way you measure it would change. Like the difference between mph/kph, the speed is the same, but the measurement of said speed is different.

 

[RX-79G]

There is a definition of the second based on the speed of light itself(the standard SI measurement of second). Sure seconds as a time unit might have come from circles and the Babylonians' base 60 but as a standard unit of measure, it came from the speed of light when the people who designed the SI system redefined all units except the kilogram based on things more universal(such as the speed of light).

Based on this speed of light definition of a second and the fact that anything in physics can't go faster than the speed of light(even matter in a black hole doesn't go any faster than light does), if the second changes so does the speed of light and the speed of light can only be different in a separate universe with different physics than ours.

Ah, nope. The speed of anything is a number of arbitrary distant units divided by an arbitrary time unit. We can define those units by "constants" like the decay of certain elements or the speed of something like light, or sound. But units of measure are a house of cards that lean on each other for definitions. There is no "speed" of anything until you agree which units you want to use and how those units are defined.

I don't think you should be attempting a hard science approach to science fiction at this point. We are discussing elementary and middle school science principles, and they should not be causing you this much confusion.