Constructing Lunar Calendars | Single and Multiple Moons

[@cadr003]

What kind of calender would develop if your world IS a moon to a planet?

[@RKH1502]

Couldn't you just pretend the planet is just a really big moon?

[@Artifexian]

Similar idea. The planet will go through phases and the locals on the moon will likely track those phases.

[@ganaraminukshuk0]

What if it's a double planet where both planets are tidally locked to each other? Would the near side use libration and the far side the stars?

[@TheAgamemnon911]

So, gas giant size then? Same deal, but they might decide to end the month every time they get eclipsed and start it again, when the moon has passed its primarys shadow. However, such moons are often tidally locked, so day and month are the same thing.

[@trinity_null]

cadr003 a terrestrial calendar

[@Taneth]

And of course the inner-moon people have been at war with the outer-moon people for as long as anyone remembers.

[@Artifexian]

1984, nice. :)

[@parthiancapitalist2733]

Artifexian What happened in 1984?

[@samdame6819]

It happened in 1949 ;)

[@tophat665]

We've always been at war with eastasia...

[@asloii_1749]

@@parthiancapitalist2733 A "utopia" according to the edgelords

[@eduardovieira303]

2:52 Seasons perception is a funny thing. I've lived in southern Brazil my entire life, and though we use the Gregorian Calendar, we don't use seasons as a reference as much as people on the North Hemisphere do. In American movies I often hear things like "we're gonna marry in Spring", while here people would probably say sth like "we're gonna marry in September".

[@Artifexian]

Ye, I'd imagine that's down to the fact that the closer you get to the equator more homogenous the year becomes. You don't (there are of course expections) crazy cold winters and crazy hot summers. It's kinda the same-ish year 'round. At least that's the impression I get and I'm not factoring in rainfall here.

[@MarcosRodriguesCarvalho]

@@Artifexian in southern Brazil, we do have cold(ish) winters (0° to 15°C) and hot summers (above 30°C) since it's temperate, not tropical like most of Brazil. and Christmas for us is in the summer, I never thought of it as a winter holiday as you mentioned. (I know this comment is one year old)

[@pixelpix1728]

Pff I live in northern brazil, almost exactly at the equator line, the only two seasons I know are "amazonic winter" (December to May), where it rains more, and "amazonic summer" (June to November), where it's very sunny, and they're not veeery different temperature-wise. Seasons here can't be used as a reference at all hahahaha :P

[@eduardovieira303]

@@MarcosRodriguesCarvalho The thing is, in places like Europe, seasons change the entire landscape, visually. Down here, the only thing that changes is the temperature. The landscape is always the same.

[@nutyyyy]

I moved from Scotland to Costa Rica and despite being in the Northern hemisphere they named the season (of which there are pretty much just two, I would call them rainy and hot and hot and dry, with cooler windier periods in between). They call the season that falls in the traditionally summer months where there is more rain as "Winter" and January is in Summer etc.

[@rogervanaman5131]

So you are saying in Ireland they put the summer solstice in the middle of summer? That's interesting, the solstices and equinoxes being the start of the seasons has always kinda bugged me. I understand why, it makes more sense temperature wise (at least in the places I have lived) but it just feels wrong. I'm happy to see you making new videos, thought that last one was going to be it for a while.

[@Artifexian]

No, no, gonna keep at it for as long as I can. Apparently yes...to be honest it was news to me that other northern hemisphere countries placed may in spring. Mind blow.

[@seraphina985]

+Artifexian For the most part differences between calendars divided strictly on astronomical events and those with different seasons is the latter is usually delayed compared to the former to match up with the state of the climate. Climate shifts due to the seasons are delayed by the buffering effects of the planets atmosphere and hydrosphere but of course when your calendar is mostly built for agrarian purposes it's the climate you care more about. Since it's that which tells you when it's safe to plant your crops and not fear them being destroyed by frost for example.

[@yashtibrewala1411]

The Hindu calendar fixes the drifting seasons by adding an extra month every three years (32.5 lunar months to be precise). And they have sorts of traditions and customs around the extra month too. Like no marriages can happen in this month, etc. *EDIT:* Just realised after watching the end of the video and basic googling that that would make it a lunisolar calendar!

[@amazon37mustafa9]

trash

[@xmvziron]

@@amazon37mustafa9 No, Artifexian made a video on it.

[@RKH1502]

9:07 Heh, yeah. Where I live, winter is basically mid-October through mid-April, summer is the rest, and spring and fall are just buffer zones between the two where either everything springs to life all at once or everything dies all at once.

[@Artifexian]

See, totally dependant on location.

[@hellothing]

RKH1502 australia?

[@jakobholm6343]

more likely the complete opposite considering australia has summer dec-jan-feb but its hot all year pretty much

[@aaront3049]

I really appreciate all of the links you threw throughout this! Looks like my afternoon is gone and it's time to jump down this glorious rabbit hole

[@CJLloyd]

I'm so happy you're posting videos about calendar building. Actually I'm so happy about everything you post. You're genuinely one of my favourite KZbinrs. It's like you're just a guy who is into all the things I'm into - really: the conculturing, the astronomy, the conlanging, the calendars, the music (ok, that's your other channel, but still) - but just goes about them in a slightly different way, which is always fun to see and learn from. Great job, man, seriously great job. I hope you have the time and resources to continue this long into the future. Do you have a Patreon page? I'm sure many people would love to support you.

[@Artifexian]

I don't have a patreon page for the channel. I've one for my podcast though. This might be something I will look into in the future if I ever get the chance to go pro with this youtube thing.

[@SimonClarkstone]

Artifexian an advantage of Patreon is you can get your Patrons to spot all your typos before release to the public. Not that KZbin offers a good way to fix them.

[@Chiefwerewlf_Records]

Thank you for coming back! I really enjoy your episodes and they've helped me with world building and writing. It is a wonderful thing to have a gas giant with a Habitable moon. :)

[@hcblue]

My grandparents are ethnically Javanese, who traditionally use a lunar calendar (Anno Javanico, AJ) with 10 divisions per day (5 daylight and 5 nighttime divisions), 5 days per week (named Pon, Wage, Kliwon, Legi, and Pahing). My grandparents-and it's my understanding a lot of modern Javanese-use a combined 5-day and 7-day week to create a 35-day month called "Wetonan" (the combined day is called "Weton"). Probably not a coincidence, but there's also a 210-day Javanese calendar (6x 35 days) that I'm less familiar with called "Pakuwon". Growing up, I remember my grandma always said that a "Legi" Friday is a good day to make large changes in life (celebration, graduation, engagement, etc). Anyway, loving the videos, Artifexian! :D

[@cyndie26]

7:45 Thanks for accepting my suggestion. I didn't even know that it was being used in a sci-fi series.

[@Artifexian]

No probs, couldn't not mention KSR.

[@airmanon7213]

Huh, never knew that bit about May falling in summer. Pretty cool.

[@Artifexian]

In Ireland at least. Dunno if it's like that anywhere else in the Northern Hemisphere.

[@airmanon7213]

Artifexian Where I am (California), summer is June, July, and August.

[@qwertyTRiG]

Artifexian I think that the British division of the seasons matches the weather, while the Irish division better matches the growth of plants. May doesn't feel like summer, but it does look like summer.

[@ragnkja]

Artifexian How is May more summery than August? Also, early May where I live is obviously not summer because the trees still have little to no foliage.

[@collindamskov]

I love the new style and the fact that you're back! I will say, it's sort of unusual if having the quiet music in the background like in your videos before, but I'm good with it.

[@srjskam]

I hope there's going to be a video about ways of subdividing the day, no reason to just plug in our 24-60-60.

[@Artifexian]

Part of the next video.

[@ganaraminukshuk0]

I went 30-100-100 with my clock system, but you have to read that in base 8. Basically... - 24 hours per day divided into 3 8hr blocks representing AM, PM, and an intermediary between AM and PM. - 64 minutes per hour divided into 8 8min blocks, as determined by the base 8 counting system. (Our equivalent is 6 10min blocks, but that's because it's a base 60 system shoehorned into a base 10 system.) - Seconds are divided the same way as minutes; 64 seconds per minute. - Is it 24-64-64 or 3-8-8-8-8-8? (Ours is 24-60-60 or 2-12-6-10-6-10.)

[@ganaraminukshuk0]

I realises that 6 10min blocks can also be rearranged into 12 5min blocks, translating to every hour increment on the clock having 5 minute increments inside. So 2-12-12-5-12-5.

[@srjskam]

Why do you have 24 hours, isn't that pretty arbitrary even in terms of multiples of 8? I'm always annoyed by binary digital clocks that show time in hours, minutes, and seconds. Naturally they should divide the day logically: 00-06 would start with 00... , 06-12 with 01... , 12-18 with 10... , and 18-24 with 11..., and further down from that. If one where to implant this reckoning of time in a constructed world, it would be easy to replace terms that correspond with hours, minutes, and seconds with for example 'first quintet' (of bits) for 45 minutes, 'second quintet' for 1½ minutes, 'third quintet' for 2½ seconds (and 'fourth quintet', 82 milliseconds, and so on for scientific use). (So 18:51:53 would be 110010010011101, or 11001:00100:11101, or 25:4:29, naturally using native, probably not 10-based numerals)

[@ganaraminukshuk0]

srjskam 'Cause my clock was based off of a base 8 or base 16 revolution (imagine the French decimalisation of time; basically 10-100-100 for the French) that worked but didn't wanna bother with dealing with the 3's.

[@morilea]

oh not bad, only 2 weeks this time. he's getting better

[@Artifexian]

A little! I'm still learning after effects and this took me like a week to animate. Hopefully, I can speed up the process.

[@aaront3049]

Artifexian Your editing definitely has been getting a lot more fancy, I like it :)

[@DTux5249]

Artifexian I've faith you'll figure it out.

[@morilea]

I do also. are gonna make more linguistics videos?

[@turun_ambartanen]

+Guiem Haielle > Yup! I just want to get these calendar videos out first. There will be more conlanging soon.

[@tylerowens]

I'm really excited to see that videos are being uploaded again. I first found the channel while it was cryogenically frozen and was sad there wasn't more. Are we going to get more conlang videos? The worldbuilding is great too, but conlanging is what originally brought me here.

[@Artifexian]

Yup conlanging will happen. I'm just need to get these calendar videos out first.

[@parthiancapitalist2733]

Artifexian can't wait to learn how to speak Oa!

[@Tesana]

Hmm, interesting. I may have some difficulty making my calendar though since I have 4 moons of varying sizes, so to ensure the moons don't get destroyed and become rings because of being too close to the Roche limit, they're not all the same distance apart. Furthermore, 3 of the moons' orbits are elliptical whilst only the 2nd most outer moon is the only one that has a pretty much perfect circular orbit. If I'm going to make a LuniSolar calendar this will be quite a task to work out accurately since the planet in which I'm setting my story is in a binary star system. This'll be quite the challenge but I hope to figure it out eventually for the sake of my storey's lore.

[@messenger3478]

Artemis Fowl my world has 4 moons. I think I maybe bit of more than I chew.

[@niydfass1060]

that's a lot of celestial bodies.

[@RobertRumble]

I have three moons. so if the inner moon is x then the first moon is x-1 and the next one would be x-2? based on the orbital period?

[@sehr.geheim]

So, what did you come up with?

[@uayninaduian4989]

I made a planet that has a 21 earth hour day but I was also trying to make a native system of time rather than follow the Earth time system, and it was far more complicated than I had thought it would be. Thanks for your videos Edgar, yours is my favorite channel on KZbin

[@Amozmusicmaker]

I'm so glad you are back, can't wait to see more of the conlang series, it's one of my favourite series on youtube and i've been wanting to create a language myself for some time now. Also, how would you create a calendar for a double star system?

[@Artifexian]

Copying for elsethread. Tl;dr treat double stars like single stars. Double star systems will be exactly the same as single star systems. If you are in a tatooine-like set up the stars will necessarily be so close together so as the function as a single star in so far as calendar building is concerned. If the two stars are separated they will necessarily be separated by a huge distance, so again it's like working with a single star. That said in the case of the tatooine setup your locals might track solar eclipses - when one star eclipses the other -and hard bake that info into the calendar somehow. This might be their weeks if the duration is sufficient. Let your creativity run wild. :)

[@wilcojar]

I made a spreadsheet of my own before watching this series that uses the size of my planet, and it's apparent visual size from the planets surface at sea level, along with each bodies rotation if any and revolution around it's gravitational axis to create lunar, solar, and lunisolar calendars, and then a comparison to a cultural calendar. When I set it to earth, our star, and our moon I was able to accurately compare it to real life solstices equinoxes and lunar and solar eclipses. The inputs became a cultural calendar input and the location using degree coordinates. I used this to make my own world which had 3 moons.

[@Tetracarbon]

I thought you weren't updating your channel anymore. Welcome back. I love this video! :)

[@TreetopCanopy]

This video is so thorough, detailed, and perfect. Thank you!

[@evanev7]

Artifexian dedicated to being the best youtuber with the 9:59 video. Glad youre back!

[@samdean3999]

he is uploading again!

[@Artifexian]

He is!

[@CarbuncleWishes]

I am so so happy you're back you are who inspired me most to pursue conlang and world and word building, now Im in the middle of developing a pair of sister languages for my fictional world while learning Esperanto! looking forward to more content!

[@ottrr_]

Edgar! Another video! So glad to see you back and crackin'. Hey a question (and perhaps idea for a video down the line?): you keep mentioning solar calendars and seasons, and it got me thinking: what would a solar calendar on a planet without axial tilt look like? I mean, obviously it wouldn't be structurally very different, but seasons would not be the main consideration. Perhaps on an aseasonal world, solar calendars would be much more rare because there would be no natural incentive to notice the yearly cycle of the sun. I recognize there would still be some minor seasons due to the eccentric orbit, but it's a rather interesting question. Anyway, I gotta say I really enjoy hearing bits of world building in your vids--it gives some nice lighthearted context to the science. Hope to see another video sometime soon!

[@JayAlcala23]

Edgar! It's nice to see you back, and making videos. Really liking the new animations, looks amazing. Keep up the work.

[@Artifexian]

Will do.

[@HankScorpio]

Two videos?! You're blowing my mind Edgar! I thought we were only getting one as a little bonus. Does this mean the channel is back to regular videos? The dream is coming true here, don't say no.

[@yaumelepire6310]

Where I live, perceived seasons go as follow: Spring: April and May, which corresponds to the blooming of the trees (even though we sometimes have to wait well into May before that happens); Summer: June, July and (sometimes) August, which is the period of time when we can be comfortable outside without warm clothing Fall: September, October and November, which is from the time we need to start dressing up to go outside and the first snowfall; Winter: December, January, February and March, which is roughly from the first snowfall to the trees blooming.

[@nikolajankovic96]

Are you still working on your language?? That was my favourite series on whole KZbin!!!

[@Artifexian]

Yup! I just want to get these calendar videos out first. There will be more conlanging soon.

[@nikolajankovic96]

GREAT ;)

[@adirmugrabi]

i'm subbed for the language too

[@DTux5249]

I came for the conlang stayed for the world building

[@parthiancapitalist2733]

adir mugrabi calendars are helpful in the semantics of language :)

[@njcwolf4654]

I'm so happy you're back!!! I don't know if you still read and reply to comments 3 hours after you uploaded, but I missed you! Remember how you made that video saying you got a job that was gonna prevent you from making videos on this channel for a while? Well now I finally got my first job and it's preventing me from watching your videos right when you upload haha (reason why this comment is 3 hours late). Jobs jobs jobs! They get in the way of everything!

[@Artifexian]

Gotta make ends meet.

[@lucillefrancois150]

My dude! It's just so good to have you back.

[@satrinala]

This video is amazing, I barely understood half of it but even then I could tell what you were talking about? Which probably doesn't make sense, but it's what I got. Also; I've always kind of wondered about the way some months are "supposed" to be in one season, even though it never felt quite accurate to me, so that last clarification answered a completely different question about the same thing, thank you!

[@mariostar13]

7:47 - Or better yet, you could do something similar to leap days with this. With your 16min 10.484sec of "time slip", you could add extra time to certain days every once in a while to realign things periodically.

[@ivx8768]

He's back, and the new grafic style is great

[@christiaancoetzee1696]

"A winter festival in spring is no winter festival in my eyes" The entire southern hemisphere: 😔😔

[@theskeletonposse6432]

I was hoping you were gonna tackle Lunisolar calendars at some point. Glad to see that they're your next stop!

[@Artifexian]

The one true calendar imo.

[@ConflictedCrisis]

He uploaded ANOTHER one! The absolute madman!

[@Artifexian]

Haha

[@MrRyanroberson1]

well, nice to see you alive! I got here just after you left... and I was so alone :( just under the hours, insert this function into the box for remainder minutes to give better perspective, for CELL is the hours cell location: (CELL-floor(CELL))*60 so, I wonder.... if I have 3 moons in different orbits 2:3:5 and a year of about ~13 inner moons.. things get weird fast. so the solar year is 13, 8 2/3, and 5.2 months long each, with days/month of 36, 54, 90 days.. that's messy. so the culture are very determined to keep tradition in mind, hence why they'd keep the lunisolar calendar of 13 months, the religious calendar of 9, and their third moon that they use for our equivalent of astrology (ooh so your personality is xyz because the phase of the third moon lined up with jkl)

[@amicaniiya1576]

I'm currently creating a planet with two moons, the smaller orbiting the bigger one, but while I was calculating and drawing out everything I noticed something: The orbital period isn't exactly the same as the time between two full moons, the longer the orbital period of the moon the bigger the difference (ex. my bigger moon takes ~56.2 days around the planet, planet mass/size, sunmass/size and year length are the same as with earth and there's a 10(!) day difference between orbital period and the phases). You have to consider that the whole planet/moon(s) system orbits around the sun and the angle of the light changes. For a full or new moon, it needs to fall along a radius of the planet's orbit, half moons on the orbits itself. I only notices it when I drew out and traced the orbits, so I don't blame you for not noticing it ^^ your videos are a big help with my worldbuilding!

[@veggiet2009]

I like the "both" idea, I imagine any culture using celestial objects as chronometers that has two moons would probably develop a system that combines the periods of the moons, like maybe a different month begins every new moon of the primary moon, but what that month is exactly is dependent on the phase of the secondary moon, you could end up with a calendar that has 8 different months, each labelled by the phase of the secondary moon.

[@sweetintoxitacion]

I missed your videos so much! I'm glad you're back :) Love your accent, by the way

[@Artifexian]

Oh god. I hate it. I can't say 'th' which the internet loves pointing out to me. :/

[@enkiimuto1041]

I waited a year for this video, thank you so much for coming back!

[@ana-ov3fd]

Hey Edgar I just wanted to mention the I like your old video style. Like the ones where you draw instead of using animation. Love your video topics though. Still waiting for an update on your language OA and your base 12 counting system. Happy your back!!! -Tuana

[@cosmonautcries8099]

Yo thank you for making these videos they inspired me to make a calendar for my end of time civilization

[@namelastname5844]

The last time I was this early artifexian actually posted And this joke was original Oh wait it never was

[@Artifexian]

Hehe

[@gabrieldoudna6570]

how can anything never be original?

[@Gashnaw]

My DnD campaigns are so detailed thanks to your videos Art.

[@Artifexian]

No probs, that's what I'm here for.

[@JosephKeenanisme]

There's also the perceptual nature of a season as well. It doesn't matter if it's before the solstice or equinox people will say it feels like winter or summer. And Edgar, in the US we have a holiday that's the last weekend of July, it's what most people think of as the start of summer even though it really isn't. It can vary by culture and even within that a region where you're brought up.

[@DaffyDaffyDaffy33322]

sooooooo glad you're back :D

[@Artifexian]

Glad to be back, pal.

[@tavdy79]

Re. the whole May = Summer thing; as you pointed out, it's kinda arbitrary. In Ireland, Summer starts in May; in the UK, it starts in June; and in the USA, it starts in July - which means the Summer Solstice - AKA Midsummer's Day - falls in Spring in America, in the first month of Summer in the UK, and in the middle month of Summer in Ireland. (Yay for the logical Irish!) This also applies to the Spring and Autumn equinoxes and the Winter Solstice. But it gets even more arbitrary than that: in most temperate countries the year is also divided into two unequal halves, a shorter five-month Winter (last Sunday in October through to the last Saturday in March) and a longer 7-month Summer (last Sunday in March through to the last Saturday in October). This means that, for a few days each year at the end of March, it is simultaneously Winter in the USA, and Summer in the UK and Ireland.

[@Artifexian]

Wait! What! Summer starts in June in the UK...how did I not know this?

[@tavdy79]

I didn't know that Summer starts in May in the RoI until you mentioned it. I'm now wondering how it works in NI though. Do they follow the rest of Ireland, the rest of the UK, does it depend on whether you're Nationalist or Unionist, or something else? And then there's all those New Years. The town I live in is, accounting for size, the most ethnically diverse town or city in Europe, so I had a quick count and found eight New Years that are, or have been, observed here - Scottish (Hogmanay) Chinese, English historical (March 1st I *think*) Jewish ecclesiastical, financial (April Fool's Day) Jewish civic (Rosh Hashannah) Pagan (Samhain) and Muslim.

[@ntm4]

Actually Summer starts in June in America too. We call June, July, and August the summer months (even though we say summer actually starts on the summer solstice so it's really a bit of June, July, August, and most of September).

[@burtenplays]

This is quite old as far as the internet goes but definitely don't worry about making small mistakes. Nothings perfect, not people, not machines, not computers, not anything. You'd be surprised how many people just miss an error entirely to automatically correcting an error without even thinking it. For instance I do let's plays, not good ones it's just how I roll. If someone complains that I don't know what I'm doing, am are slow or messed something up I just remind people that that's what I do. If you wanted perfect edited headshot highlight gameplay well there's always another channel for that. Gotta say all your world building vids are super interesting. I dipped my toes in some minor stuff for a D&D campaign that never happened and vidjio games that never happen but never thought about how far you can go with it. Just doing little things here and there as a hobby every once in a while can probably spawn a massive scale universe that you can use for alot of smaller projects like said video game as long as you keep on that same project of course or don't lose your notepad. You can have two games set in the same system such as the example you said here with the two different civs on different moons, you can eventually reveal that's what all the evolving dark spots are or you never even have to mention it and just blow someone's god damn mind later. Very cool.

[@Sabersonic]

Interesting and thought provoking video as always Edgar, especially the notation on why a culture would adopt a lunar-based calendar over a solar-based calendar. Though now I can't help but wonder if Westeros of ASOIAF/GOT fame adopted the lunar calendar since, well, their seasons last multiple years. Don't recall anyone mentioning this in either the show or the wikias. Also interesting on how one would approach a lunar-based calendar for multiple moons. Though then again, this is for multiple moons on separate orbits, not ones that are in barycenter harmony or have horseshoe orbits. I can only assume that the former'll be treated as a single moon with special occasions occurring when they're in eclipse, not too sure about the latter though then again when the moons are at their closest that could signal the beginning of a new year, perhaps even a Zodiac horoscope thing where the alignment of the moon conjunction (for lack of a better word) is aligned with a particular constellation. Heck, might as well even use it to mark the year not unlike the Chinese Zodiac. Though I can only assume that there'll be a video segment in the near future discussing the keeping of time that is not similar to that found on Earth?

[@noone-ez6on]

Man i just love the LCARS graphics you use!

[@myriaml.9858]

It's really quite unfortunate that KZbin doesn't have a button to say "I already liked and am already subscribed, but if I weren't I would be now". Or at least just a second like button. Regardless, It's great to have you back Edgar, I've missed that little alien!

[@Artifexian]

I'd just settle for a subscribe button the functions as a subscribe button. Like most of my subs aren't gonna see this video because of the algorithm and this makes me sad.

[@TreetopCanopy]

Thank you so much for linking out to more videos!

[@TurnipStewdios]

Something I have been wondering about is this; what effects would a multiple moon system have on the tides of a habitable planet? Would you get extra high spring tides when the two moons are aligned? Is there some way to calculate them? What kind of impact would that be likely to have on costal civilizations, or industries such as fishing? What about the effect on sea life, or even global weather patterns?

[@tonio103683]

HEY! Hi ^^ I'm glad you came back on this channel ^^ I have a question though : you filled the day as a convenient number but what if you wanted to take again the same number you used for the solar calendar? If it's a different culture on the same planet the day should be the same right?

[@Artifexian]

Ye, so this is where my method kinda falls apart because specifically it is designed to construct a single calendar. That said, the next video will sorta touch on this.

[@tonio103683]

Ah ok, looking forward to it then ^^

[@Metaknightmare217]

1:32 Isn't it a leap day if it is an extra day to appeal to the accuracy of the definition of a local month?

[@Artifexian]

I don't understand what you mean. The way i've worked the numbers in this video means that the calendar will drift 1 day every 20th month unless otherwise corrected.

[@Metaknightmare217]

I mean that you said there would be a leap month every 20 months, but if there is a drift of 1 day every 20th month, adding an extra day would be a leap day, not a leap month.

[@Artifexian]

Ah, okay I get you. Ye, leap month is probably not the best term to use here. But as long as everyone gets that it's an extra day every 20th month then we're ok.

[@Metaknightmare217]

Of course, no problem. Can't wait for the lunisolar calendar episode.

[@jonathongoulding9780]

+Artifexian I know this is quite late, but my tribe also uses a lunar calendar and we actually use it to better identify seasonal shifts and ecological patterns than the Gregorian calendar does for our homeland. We have 12 months named after the ecological event of that time and we fix calendar shift by having a full month called the "Lost Moon" added on every 3 years. This means a culture can have a lunar calendar that works better than solar ones for the purpose of ecological tracking (we determine seasons based on what the animals and trees are doing at the time) and solve drift by adding an extra non-existent lunar cycle to the year... a leap month, if you will.

[@scars2k2]

Loving the LCARS format @Artifexian

[@Artifexian]

All the nerd references all the time.

[@pedrom.c.seabra8671]

This came just in time! I've been trying to create a calendar for a long time. An enormous help, thanks for the great video! PS: One of this days you have to make a video about binary planets.

[@sarkycanadian1394]

"let's all take a minute to appreciate the mouthfeel of 'Waxing Gibbous'

[@complex314i]

May is virtually always summer for me. In my home town of Phoenix Az, summer starts on the first day of the year where the temperature reaches 100°F (approximately 37.78°C).

[@alanepithet2931]

This sort of stuff is ridiculously cool. I will note that most of it is only relevant if you're building in a low fantasy or hard sci-fi setting. Once you drift into settings where 'physics' are suggestions rather than hard rules, more and more of your setting can play fast and loose with what we consider to be absolutes, and you really only need an excuse, rather than a reason. The god of the moons may like having one moon that's particularly zippy, and the other might move comparatively very slowly, but so long as there's a god of the moons sitting around, neither of the moons will fall out of orbit.

[@Aryman]

6:14 How many days and months has year in this option?

[@drgn2580]

Hey Artifexian, great video. Maybe one day you should also do a video about sidereal and solar days.

[@ThatOneLadyOverHere]

It's really interesting that May is part of summer in Ireland. Little fun fact for my pocket! Our summer starts on the solstice on June 20 something.

[@alexbedel6320]

I would love to see calendar recommendations on how to set up a calendar on a tidally locked planet.

[@soton4010]

This helps a lot. Thanks. As always keep working for that pie.

[@nicaustin3911]

Oh god it feels good for Artifexian videos to be back

[@Artifexian]

Thanks pal. Glad to be back.

[@Mattrons14]

Amazing content coupled with amazing animations! I know how long it can take to animate something so two weeks are an impressive speed!

[@venavis4345]

You are a wonderful resource for my upcoming sci-fi story.

[@pizdamatii5001]

great work as always. it's always nice hear your ideas and learn interesting details about different cultures on earth. since you've mentioned kim s. robinson's mars trilogy, i wonder if you would address the issue of months (that match seasons) on a planet with a more eccentric orbit than our own. in "a case for mars" robert zubrin has a short chapter dedicated to this. short excerpt: "But equipartitioned months don’t work for Mars, because the planet’s orbit is elliptical, which causes its seasons to be of unequal length. In order to predict the seasons, a calendar must divide the planet’s orbit not into equal division of days, but into equal angles of travel around the Sun. If we want months to be useful units and choose to retain the terrestrial definition of a month as a twelfth of a year, then a month really is 30 degrees of travel about the Sun."

[@carsonmerkley9710]

Great work, your videos are fantastic.

[@Artifexian]

Thanks, pal. Glad you enjoyed.

[@Lucy-ng7cw]

Holy shit, I didn't realise you were back on videos...I was on holiday at the end of June.

[@Artifexian]

Yup!

[@eainen]

love the okudagram graphics :D

[@faebird6396]

I missed this channel! More! Have you thought about making a picture book of your world building stuff? Would be so fun to read. Just think, World Building Made Easy, a series of small books that are for ages 8 and up.

[@StraboSE]

The Roman Catholic Liturgical Calendar is really interesting because the seasons of Lent and Easter shift around within ordinary time due to the lunar calendar determining passover on the Jewish Calendar - since easter must always come after it, and Christmas on a Sunday means an early Advent, but most of the rest is based on set dates on the Gregorian calendar. It is this strange due to both devotion and politicking and as such it is very interesting to base ideas off.

[@2712animefreak]

One thing that you're forgeting is that the time it takes a moon to circle around the planet (sidereal period) is not the same as the time between the same phases of the moon (synodic period). This happens because the planet revolves around it's star while the moon orbits it. For example, the sidereal period of our Moon is about 27.3 days but you see a full Moon only every 29.5 days. For the duration of the synodic month you can use the formula: (1/T)=(1/M)-(1/Y) where T is the synodic month, M is the sidereal month and Y is the sidereal year of the planet the moon orbits, all in days. Just imput T instead of the "Orbital period (Moon)". Similarly the "Local day" that your table calculates is the synodic day (interval between two noons), and is not the real sidereal rotation period.

[@swordfireguy5869]

YAY! Another video!

[@Artifexian]

Huzzah!

[@swordfireguy5869]

WOAH! U replied!

[@swordfireguy5869]

Artifexian, your videos are really helpful while creating a fictional world! Thanks for helping us viewers!

[@haileyross5335]

Hey just wanna say love what u do and thanks for making my worldbuilding so much easier :)

[@thetimetravellingtailor6323]

You can definitely still have seasonal festivals, though. Instead of having a specific month date we could say that winter happens on the fifth day of winter. It will land on a different date each year but that's what Easter does.

[@jimbuddha]

The warmest months in Ireland are June, July and August, so you could say it depends on how you define the seasons.

[@Demotalias]

Yay, you're back! Love your content. Will you still do your Game of Thrones video?

[@Artifexian]

I said I'd do a game of thrones video??

[@Demotalias]

You said maybe to be correct^^ At the end of your Seasonbuild video about axial tilt.

[@RaghnaidAnnaNicGaraidh]

Growing up in Australia I was told that winter was June-July-August, so I assumed in the northern hemisphere that summer was June-July-August. That said, the Gaelic (and Middle Irish, although not modern Irish since you have a loan-word) for "May" means literally "first summer weather", so it doesn't surprise me that you'd have been told summer is May-June-July.

[@palatasikuntheyoutubecomme2046]

And plus, then summer solstice is halfway between

[@RockinTheBassGuitar]

The hot season where I live starts in May and sometimes lasts through September, it's even been over 90 Fahrenheit in the beginning of October. Living in a desert can get weird.

[@milojacquet7507]

just for those who like making calendars enough to scroll down the comments of a video, it's fun to build a calendar around those decimals, adding complicated (but hopefully simple) leap days/months/seconds to counteract drift. I agree, though, for a fictional setting, just fudging the ratios is easier for everyone.

[@kalez238]

Omg, I don't know why, but I laughed so hard when you said you misspelled worldbuilding. Human nature, bro. :P These new videos are making me think so much more than I expected them to. I hope you keep making them this regularly. On that topic, are you actually "back"?

[@Artifexian]

Funny thing is I must have watched that intro about 20 times whilst I was creating it and I even showed it to multiple friends to get their thoughts and know one spotted it. It's like our brains saw worldb - yup that's worldbuilding no need to read further. So, I'm off for the summer which gives me the time to work on these videos. Gonna make a concerted effort to continue these videos during the academic year but I really don't know how it's gonna go. I'm trying and hopefully I'll succeed.

[@kalez238]

In the writing community, that is what we call being too close to the problem :P Well, thank you for trying, at least, and making as many as you can. I'll be here watching and waiting :)

[@dliessmgg]

Idea: A planet with two moons, and every time one of them has a new moon, a new month begins, leading to easy irregular month lengths.

[@xxkaiserxx6240]

As always, great video! By the way, do you have any plans for more language videos? I absolutely loved them...

[@flinko99]

Is there gonna be a video about how to figure out a calendar that tracks another planet/moon orbiting the parent body, including months? Would it just be "okay, these are their seasons" or is there something that makes it possible to figure out the other world's phases?

[@Artifexian]

No, because otherwise I'd be making calendar videos for the rest of all eternity. And also, why would a culture track another planet as there primary time keeping device? They'll likely go the biggest brightest objects in the sky - the sun or the moon. Or if your setting is a habitable moon orbiting a gas giant then they'd likely track the gas giant's phases. Same method outlined in this video applies to gas giant phases.

[@covenawhite4855]

Traditional Hindu astrology is based on the sidereal or visible zodiac, accounting for the shift of the equinoxes by a correction called ayanamsa. The difference between the Vedic and the Western zodiacs is currently around 24 degrees. This corresponds to a separation of about 1,700 years, en.wikipedia.org/wiki/Sidereal_and_tropical_astrology?wprov=sfla1

[@jonzeigler2811]

Think you might have missed the distinction between synodic and sidereal months. The period it takes a moon to go from full moon to full moon is its synodic month, but its sidereal month (the period it takes to complete one orbit with respect to distant stars) will be less than that. Not a problem if you're building a calendar around one moon, but if you have two moons, the resonance between their orbital periods will control their the length of their sidereal months - their synodic months won't have the same mathematical relationship, so their phases will, um, get out of phase.

[@Astronomy487]

awwwww yesss!

[@Artifexian]

Hope you enjoy. :)

[@PizzaChess69]

I have a crazy idea: How about a calendar on a tidally locked red dwarf planet that is entirely based on the movements of other planets in the sky? I imagine a red dwarf system with 4 or 5 planets, 1 or 2 of them in the habitable zone, all tidally locked, and standing on any planet, you can clearly see the other planets in the sky moving. Since there is no day-night cycle and the star always appears to stand still in the sky, the movements of planets would be the only way for any civilization to track time.

[@redstreak1]

What about calendars for multiple-suns? That would especially be relevant toward P-type systems. Seeing the option for multiple moons here was good on that note, and made me wonder if something similar would be taken into account with two (or more) suns orbiting each other especially if their fluxing compounds the seasons; a star making a bright approach during winter for instance. Could there be 8 seasons instead of 4 under some extreme situations regardless normal pairings of solstice and equinox?

[@MGDrzyzga]

I've started pondering the calendar for my world - it's got 4 "moons." One similar to the moon we know. Two moonlets that orbit this moon. And one gigantic mothership wreckage. I'm imagining a calendar that bases its months on the moonlets - basically 1 month = both moonlets eclipsing each other and the major moon. I was inspired by the second opening for the anime So I'm a Spider, So What? Its first scene includes two moons of a moon, one orbiting in retrograde so they slide in opposite directions in front of the big moon. It was such a cool image, so I'm just stealing it and downgrading these moonlets to non-spherical minor moons because that's a little more realistic.

[@greysonmonaghan-bergson3455]

HES BACK I HAVE A REASON TO LIVE AGAIN

[@Artifexian]

Huzzah!

[@Frankdude72]

Thank you soooooo much for making these videos. :D

[@Artifexian]

No probs, and thank you for watching. :)

[@hanslee475]

Edgar, when you finish the calendar videos, will you feature some conlangs and worldbuilds from fans?

[@MisterManDuck]

You're spoiling us!