Constructing Lunisolar Calendars 

Solar calendars: I get it Luner calendars: Seems legit Lunisolar Calendars: wut

Glad to see my people's calendar featured!

The international fixed calendar is a great example of a calendar that is completely regular. 13*28=364 Plus one spare day that rests outside the other thirteen months. Every month is exactly four weeks, which makes everything much easier to deal with

8:46 Ahh yes the Sea of Luxembourg.

Great video! This calendar series was really interesting!

8:12 ":: I know 12:36:48 is actually 01:00:00. I just wanted to write 12, 36 and 48 on screen. Also, I wanted to draw a digital clock! ::"

You should make a book of world-building stuffs someday. I'd buy it. And I'd buy it for all my writery friends. :)

Ah, but my planet has two moons. Actually I used dubious astronomy to deal with that, by saying that the moons orbit in opposite directions and along slightly different planes. (that's really unlikely in general, but for a body to orbit in the opposite direction to another one suggests a major impact event that could also throw off the orbital plane.) So the associated calendar doesn't measure lunar phases, but it measures orbital crossings. (which I suppose constitute an eclipse, with one moon directly in front of the other.) Hey, who says a calendar on another planet has to follow exactly the same principles as one for earth? And in general we have no existing point of reference for how a calendar would function with multiple moons, because we only have one moon. Anyway, I'm not actually sure my existing calendar definitions make sense, but then I haven't gotten around to doing this worldbuilding stuff properly just yet...

FINALLY, BEEN WAITING SO LOOOOOONG YEEEEEESSS!

Love me a lunisolar calendar, every day of the week.

I'm gonna pimp out this channel so hard; you put in the work and provided the resources to make a big problem for fantasy writers into a little one. You deserve a good return on your investment.

Your videos really are super helpful and I'm so glad you're back to doing them. Helped me more than a few times writing my next novel, now I'm a couple thousand words in and I feel like I've had an actual background to paint characters on

You call that messy? Once I built a very accurate lunisolar calendar for Earth, with all its irregularities. It had cycles upon cycles in months and days and centuries and it was a mess. It made those leap months seem like nothing! Also, base 12 time really needs to happen. Or 36:36:36.

I'm so glad you're still making videos on this channel, no matter how sparse they may be

Can't wait for more conlanging stuff!

Yesss, he's back !

Hey Edgar. Great video, so glad you're back. This worldbuilding series helped me greatly in establishing the universe for the story I'm writing. There is one thing I'm working on, which is difficult. That would be the positions of the celestial objects in the sky relative to the observer on the planet they're standing on. Just a bit of added realism to make the planet feel real and alive. I might be able to figure it out for myself. But, I think it'll be an interesting idea for worldbuilding!

The calendar series has been surprisingly interesting. I've never really thought about how something as simple as time could be so closely related to culture. It's definitely given me a lot to think about, especially as a short story I'm writing is set on a tidally locked planet, which effectively has no days. As always, your editing style and commentary make your videos among the most watchable in my subscription box, even if it is just a lot of numbers ;). In the spirit of the recent solar eclipse, could you perhaps do a video on similar big solar events, the conditions necessary to support them and the effects they may have on culture? I suppose transits, conjunctions, blood moons, regular comets, meteor showers and fluctuations in the intensity of the star would come under the same bracket, along with anything more inspired you can think of. Maybe something involving binary stars or multiple moons. As always, you are a pleasure to watch and your videos are extremely thought-provoking. Thank you, Artifexian.

Yay, more conlanging next. In fact, I have in my house a book filled with notes on my own conlang, Oqwe, as well as a pile of paper, on which is written the orbital data of habitable planets around a bunch of stars in a galaxy I created from scratch. All thanks to you, Artifexian!

Yay you're not dead

Great video! Looking forward to (hopefully) some conlanging!

Oh my god! Regular Uploads! Can't wait for the conlanging to return

HES BACK

I love how you take the time to read and reply to comments. Most other youtubers don't.

"Next video will be a conlang video" EEEEEEEE 8D

Yay, I was just wondering when this video was going to drop. I've been thinking about how one might go about creating a lunisolar calendar for Earth, one that accurately kept track of both seasons and moon phases. What I came up with was to construct two separate solar and lunar calendars that would run side-by-side. The solar calendar would divide the year into seasons, where each season starts on an equinox or solstice (normalized so that each season has the same number of days every year, and the equinox/solstice always falls on either the first day of that season, or the last day of the previous season). The advantage of this is that you can have, say, a holiday that always falls on the same day of the year (and thus the same time of the season), so this would work well for seasonal holidays, like those related to harvest or the blooming of the first flowers. Under this solar calendar, I would have the year start on the Spring Equinox, with Spring being the first season of the year. Of course, this is only for the Northern hemisphere, so in some consideration for our friends down under, I would suggest renaming the season according to the classical elements (Spring = Air, Summer = Fire, Autumn = Earth, Winter = Water). That way, those in the Southern hemisphere could still refer to, e.g. the season of "Air", even though for them it is actually autumn, not spring. The lunar calendar would be divided into months as one would expect, with each month starting on a new moon. When the months don't line up exactly with the solar year (which will be most of the time), I'm not sure if the first month should start _before_ the end of the year or _after_. The lunar calendar could be used to track cultural holidays that are less dependent on the seasons. Of course, there's also the third, weekly calendar. Nobody really thinks about that that much. But I'm curious how long it would take for all three of these calendars to realign themselves. Or, how long would it take for them to realign themselves on some arbitrary first day of the year? To make this even more interesting, let's say that the solar calendar uses the tropical year (which is all about the seasons, so that makes perfect sense), while the lunar calendar uses the sidereal year (which is about the position of the stars, and is about 20 minutes longer than the tropical year). How long would it take for everything to realign under these condition? We could designate this as another unit of time, an "era" or "eon" or something.

I can't wait for the conlang video!!! Not that I dislike calendars, I just love linguistics

I was JUST going to ask if your conlang-related content would continue! Oa inspired me to creat my own conlang, and even though I don't really know what I'm doing, it's really fun. Great vudei as always, the new editing style took a moment to get used to, but it looks really good :)

Back from the dead! Happy to see you again.

So happy that you're making videos again.

O: CONLANG AGAIN YAAY. you have no idea how much your conlang vids influenced me. it is awesome

I literally spent a couple hours watching all three of these calendars to try to form a calendar for various Star Wars planets, with the existing info, just because I was bored. This was very useful though. I'll definitely use these again if I ever need to come up with these numbers from scratch

I clicked in this so hard

Just in case anyone is interested in doing this themselves, that 'brute force' bit could be completed in one, automatic, step with the 'goal seek' function on excel. Just as long as the cells are linked, goal seek on the cell you would otherwise be 'brute forcing', and set one of the cells to whatever value you would like. If it's possible, it'll find it, otherwise, it'll leave you as close as possible, to as many decimal places as you've set the cell to default to. Good luck to everyone, And thanks Edgar, I'm enjoying the new vids muchly! :)

I was going through the entire process of making a calendar (star, planet, moon(s)), and in my exhausted fury, I forced a lunisolar calendar. I was changing the lunar orbiting distance by tenths of an Earth radius. I needed that perfection and now it slightly frustrates me that the only way to get any sort of disorder would either be to remake it all, or force in leap months. Both options are equally frustrating. CURSE YOU EDGAR FOR FORCING MY HAND. jk ily Arti. I'm glad i went through it all.

Conlang!!!!! I thought you where only gonna do one of the two. So so happy that you decided to keep both!!!

My first Artifexian video caught since subscribing. I eagerly await the next Conlang video.

DMs: "Don't build lore your players will never run into, it's a waste." Worldbuilders: "So we'll just redefine what day and hour even mean and not tell a soul."

A while back I was into dozenal and thought that base 12 was really the way to go. However, I'm not so sure anymore that base 12 is actually better than base 10. This mostly comes down to gaining a slightly easier divisibility for 3 at the expense of really difficult divisibility by 5. Now I think that senary (base 6) is the best of the bunch. Not only does it have almost all of the advantages of base 12, but it also has easy divisibility test for both 5 _and_ 7, meaning that base 6 handles the first four prime numbers fairly gracefully. The only real drawback is how small base 6 is; the same number in decimal would require more digits to represent in senary. Think about trying to memorize phone numbers when they need three or four extra digits. The solution to this is to compress base 6 into base 36 somehow, which would result in numbers that had far fewer digits to represent the same value. The downside is that it would make math more complicated, but that would be alleviated if the base 36 numerals were designed such that it was easy to convert between base 6 and base 36. Not that most people probably care about this, but I think it's interesting.

Really appreciate this guide, its super interesting. However, I'm kind of confused as to how seasons would line up in this calendar form. Would winter end in a different month when there's a intercalary year added? Wouldn't that mess up the seasons for the next year? Any help is appreciated

So glad to see more new videos.

So excited to see a new video from you! Very very excited to see more linguistics! (Sorry to be that guy but you spelt Metonic Cycle as Metonic Cylce at the beginning)

ooh yeah! Conlang are my favorite episodes

Accidentally came across this video... Time to dig out my old lunisolar calendar creation attempt!

I'm so glad you are back.

I have a culture in my worldbuilding project that uses a lunisolar calendar. They have a year of ~388.863 days, and a lunar period of ~42.236 days. Most years have 9 months, but the 1st, 5th, 10th, 15th, 20th, and 25th years in their 29-year metonic cycle have an extra 10th month. Their calendar is designed so that the month begins with the full moon (which has religious importance in the culture), and the New Year coincides with the first full moon after the spring equinox.

Thank the lord for this channel. Never stop making videos. ;-;

Robot CGP Grey! that was great man

Hes finnaly back

THE GOOD ARTIFEXIAN IS BACK EVERYBODY. YESSSSSSSS.

Just wanted to throw a little trivia here; that thirteenth month (Adar II in the Hebrew calendar) is usually added to ensure that the Nissan--the month when Pesach (Passover) occurs--always falls in the spring as stipulated in the Torah.

I've found that dividing your year in earth days by your number of months (Cell C25/E25, or using the equation =C25/E25) will give you whole numbers for the year in local days and month in local days, although that may just be my setup Edit: It seems that using an equation like =C25/(E25*X), where X is a fraction with any denominator under a power of two (Like 7/8 or 49/32) seems to work up to a certain point with certain setups, this may need more experimentation Edit 2: It seems these "perfect denominators" can be found my combining consecutive powers of two (ie 256+128=384 16+32=48 Edit 3: On further inspection, these numbers all seem to be the result of dividing or multiplying 1 by a multiple of 3 (ie 0.333... or 0.166...), still may need further experimentation

Ridiculous time-based excitement about this new video!

Congratulations! You made the Chinese Traditional Calendar

9:10 - you really like that podcast huh ^^

But if you have multiple moons, do you have to track all the moons in the Lunisolar calendar, or could you make multiple calendars based on which moon(s) are used?

He he he, CGP Grey there at 9:12. Since to see him again. Unfortunately, he has not put out anything reasonable in a while. Anyways, thanks for the video, Edgar! Lunisolar calendars are the best. I think the Buddhist calendar is a lunisolar one.

"Metonic cylce" I'm sorry, I needed to point that out. So sorry.

It's like you never left

I was wondering if you would consider making a video on geography building. I have some very basic understanding of how the shapes of our continents define the weather in different parts of the world (why deserts form where they do, how hurricanes come to be...) but I'd love to see a video about how this knowledge could be applied to create a world from scratch. This would influence where the first large civilizations start to form, what problems different people around the world would have to face, it could possibly even define which zones are inhabitable or not. I started drawing some fictional maps and I started to realise the importance of where to place continents, mountains and oceans in order achieve the desired climate zones in my world.

You're a minor math genius because even with this video it still makes my head hurt trying to do this with results I actually want.

"Tirteent Mont" those are the two best words I have ever heard lol

HESSSS BACKKKKKK

You might not remember but like ages ago you went to willow park school for science week and told the kids about what you do and world-building I was one of those kids and I have been watching you since thank you for making me love world building

When Artivexian uploads Its a godly day

I was worried I would never see this channel upload again.

dude. you are a fucking genius. i discovered your channel today and i totally LOVE it!

I'm not sure what kind of calendar the clans in the Chronicles of Ancient Darkness series use. On the one hand, the use of the term "moons" suggests a lunar aspect, and there are special days like midsummer or midwinter, which are connected to day length and that suggests a solar aspect. Michelle Paver's website lists the moons and the equivalent months, and apparently there are only twelve. Also, the names of the months typically come from a plant or animal associated with that food source - like the Cloudberry Moon, the Moon of the Roaring Stags, or the Moon of the Salmon Run. There is also the Moon of No Dark, which is when Midsummer happens. Anyway, what do you think it could be? Also, if you're not familiar with those books, they're a fantasy series set in hunter-gatherer times and written by Michelle Paver - and personally, I consider them to be a prime example of how to worldbuild. There are a lot of references in the books to the clans' mythology, culture and belief systems, but Paver's careful to strike the balance between enough detail to show off her worldbuilding and not so much detail that it drags the story down. Plus, she often explains her research and real-life counterparts to, say, the taboo against mixing the Forest with the Sea, in the author's notes. They were one of the earliest book series I read - and the best, in my opinion - and I think you'd enjoy them.

The fact that you don't speak with dental fricatives frustrates me to no end but I love your videos anyway

I've been really enjoying the timebuilding videos. Could we get some follow up explaining the irregular placement of embolismic years in the Metonic cycle? Also, if you're moving on to a new category after this, I'd like to throw in my vote for cultural geography. Groups of related cultures, population migration, shared and related customs, etc. It's easy to fall into the "Culture A lives over here, Culture Q lives over there" trap when worldbuilding, but the reality is so much more interesting than that.

There is a program I think people should use when worldbuilding and that program is SpaceEngine. Currently it is one of the best tools to use to explore not just real life stars, planets and moons but also very accurate procedural objects as well. You can also use it to make your own solar systems and galaxies like I usually do. Should talk about it one of your next videos about worldbuilding.

WHY DID I NOT SEE THIS IN MY FEED?!

My one true base is base 16 and 8 because powers of two for the win!! Also, since a circle is divided into 360 degrees and is closely linked to the year, how do you divide a circle?

oh cool now lunisolar eclipses

08:12 i spend so much time figuring out what you wrote there :)

I like how you made the robot CGP Grey.

One thing to keep in mind is seconds are scientific. Under 1 atm, it takes 1ml (weighing 1 gram) of water to heat up 1 degree celsius by applying 1 calorie in 1 second. This 1ml of water also has the dimensions of 1cm x 1cm x 1cm. If you're planet has similar laws of physics and your people's culture makes them want a scientific measuring system, you should work up from seconds, not down from hours per day.

The CGP Grey-Bot is fantastic.

i love hearing "Good morning inter web lets world build so much" :) and can you go back to doing your old video style like when ones when you worked on Oa. I like that style better then this new one. :)

I wonder if civilizations would rather evolve into a 17 month year with two sets of seasons instead of alternating between years of 8 and 9 months.

Yay, Dozenal time!

I loved your channel! More conlanging pleaaaase!! Nerdy high five from Chile!

nice video man! dude the editing is amazing! (also, PLEASE DONT TELL ME YOU CUT YOUR BEAUTIFUL HAIR!?)

WHOOOOO YEAH MAN

This is like Christmas!

Sees lunisolar calendar vid SMASHES PHONE SCREEN

Could you do an entry on creating multisolar/multilunar calendars? It would be interesting to see options for calendars tracking any number of objects, perhaps breaking away from the constriction of the uses of even the terms "month" and "year".

For anyone who, like I, wondered what just blinked past our eyes at 8:12, it says: "::I know 12:36:48 is actually 01:00:00. I just wanted to write 12, 36 and 48 on screen. Also, I wanted to draw a digital clock!::" Now, I don't understand what he means by that. :p

I hope you do Worldbuiling videos on Geography soon, you've got a lot of stuff on creating planets, but nothing about creating their landscapes.

An interesting video as always, though I did notice that that there is no mention on what geographical locations would make the use of the lumisolar calendar system preferable over either lunar or solar, not even cultural reasons to extrapolate since both Chinese and Hebrew calendars don't have any obvious corelation to each other as to why they chose the lumisolar. It would also be interesting how a culture would adopt the lumisolar calendar that tracks the orbit of multiple moons in different orbits. I can only imagine the complexity of the calendar.

370 days, 30 days in a month. Years come in triplets based on whether the White Moon (full moon) comes on the 1st, 11th or 21st of each month. (each year ends with the ten day Midwinter) EDIT: it has to be this exact because for story reasons, the Big Thing that happens on 22 Lilymun 672 (November) is exactly 12^5 days after the Big Fantasy Historic Prologue Battle on 10 Miramun 0 (May)

you gotta do a collab with isaac arthur

This is just nutty 🥜

7:20, have the lengths of the weeks alternate, and a good mnemonic would be to call particular ones 'even or odd' (binary?) to know which one you're in by the date

Brilliant. As usual.

Awesome!

First NativLang and now you :D What a coincidence!

You should refer Saka or Vikram Samvant Calender from India. It is based on various of factors and compensating to seasons, orbits, etc.

The calendar for my worldbuilding has base 60 for seconds, minutes, and hours, and there are 32 hours in a day, 48 days in a month, and 16 months in a year. Time is recorded in the format of: Century.Year.Month.Day.Hour, such as 05.64.12.08.18 - allowing for highly accurate records of when events occurred. (When a specific number is unknown, it is recorded with two X's in place of the value.

yey! a new video!