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Kepler Calendar Design


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:

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.
I have no clue. Sorry. I think it would be an understatement if I said that you have down a ton of work on this, so good job!

Maybe divide your days by months?


Myth Weaver
Off the top of my head... Keep the months as even as you can at 65 days each. Use "leap" days or special holidays to make up the differences plus or minus as needed.
As for when spring, fall [et al] start end... You already have the season and the transitions. Local climates may vary it a bit but there would be so agreed official date [such as in the UK Autumn is officially September, October and November - even though today I an having a sunny day with 25+ degree temperature forecast for the afternoon and it feels like more like summer]