If the earth makes a complete cycle around the sun every 365 1/4 days, and the 13 moon calendar does not acount for the extra amount of day each year. Isn’t the calendar slowly drifting from it’s acuracy because there are no leap years?

If the moon cycle is 27.1 days. and there are 365.25 days in a year, 365.25/27.1 = aprox. 13.478 moons cycles in a year. So, in the 13 moon calendar, where is this .478 moon being acounted for? If it’s not, doesn’t that mean that each year, the calendar becomes a little more out of sync with nature?

The main question restated: If a year isn’t exactly 365 years, doesn’t the the 13 moon calendar loose acuracy each year because it’s rounding down?

I’m highly inclined to use this calendar because It’s so beautiful and organized, but, what of these questions?

Ok, heres a link which describes what I’m talking about.
Below there is a chart which descibres the amount of error in each calendar. The gregorian system uses ‘leap years’ to correct the error. How do the 13 moon people do it?

Where is the image of the moon supposed to be in the sky on day one of each month?

Heres some information.

(Google Calculator)
1 year = 12.3682662 lunar cycles
1 lunar month = 29.53059 days
1 year = 365.242199 days

(My Calculations)
1 year (lunar cycles * lunar month) = 365.242198163058 days

(links to use) … onths.html

I’m confused. Someone give me a calendar that is nice and even with the tropcial year and in relative sync with the lunar cycles.

Oh, and I’m also confused about the fact that 27.1 is rounded up to 28. Wouldn’t you round down in this instance? So the sidereal month would average 27? Then wouldn’t that be more in sync, but mess everything up?

Heres another link which discusses determining the exact length of a tropical year:

Explora didn’t respond yet, so I’ll write how I understand it, and he will correct me later, if I say something stupid. To tell the truth, I never was good at astronomy. :sad:
Sorry to say, but a calendar, fully synchronized with both solar year and lunar month, cannot exist with the given parameters. It can only be more or less synchronized and more or less comfortable.
If the year consisted of exactly 12 lunar months, it would also hold exactly 13 sidereal moon cycles:
year/synodic_month = year/sidereal_month + 1 (it would be –1, if the moon or the earth rotated in the opposite direction). If you see the solar system from above in one moment, and the planets form line sun-moon-earth, it is new moon now. Six months later, it’s new moon again, but, as the earth is in the opposite point of its orbit, they are lined earth-moon-sun – the sidereal moon cycle is exactly at its midpoint. Six months more – and we return to the starting position, so both the number of synodic months and the number of sidereal months in one year are integer. It would be nice, but it isn’t so, and another thing follows from this speculation: if the number of synodic months is not integer, we will not get any farther with sidereal months. By the way, one sidereal month is about 27.32 days long. I don’t know where 27.1 came from.
365.242/29.531 = 12.368
365.242/27.322 = 13.368
The reason for dividing year into 13 moons is just the fact that remainder from 365 divided by 12 is five, and remainder from 365/13 is only one. Naturally, 1/13 of the year is not equal to the sidereal month, but 1/12 is not equal to the synodic month either. The reason for using 13 Moon calendar is that 365=1328+1 is simpler mathematics that 365=731+430+128 or even 365=531+730.
Moons are not synchronized with moon phases. If they were, we would get a lunar calendar. It would consist of twelve months of 29 or 30 days, each beginning with new moon. But it would not be synchronized with the rotating around the sun, so solstices and equinoxes would float around some average points. Many religions use calendars of this type, and many religious events depend on moon phases. But what the modern civilization (depending on agriculture) needs is synchronization with the solar year – 365 days, and months of about 30 days are just a tradition, which came from older lunar calendars.
Only lunar calendars can tell, what exactly phase the moon will be on an arbitrary day. But every calendar with months of 30, 29, 31, 28 days (and 13 Moon Calendar, too) will let you know approximately the phases for the next month or two, if you know the current phase. Every phase is about 7 days long. That’s where week comes from.
Leap years: there is no leap year in the 13 Moon Calendar. In fact, it is taken into consideration, but it is hidden. The same time, when leap day appears in the Gregorian (in 13 Moon it is Galactic Moon day 22, Blue Monkey), 13 Moon Calendars prolongs one calendar day. 22/8 is thus two days long every fourth year. The reason for this attitude is that the parameters of planetary movement slowly change. Some time will pass (who knows, how much), and we will need leap year no more. If the rules concerning leap days were an inherent part of the calendar, it would have to be changed several times before it happens. Now, when these calculations are left outside the calendar, it can be used much longer than any calendar with separate count of weeks and years. No reforms with 10 days’ jumps – the leap day is just inserted when it needed for synchronization. Now it is every fourth year.
Folks in the movement believe they will be able to stabilize the earth and make the year equal to 365 days forever by creating a global telepathic field. :wow:

Alright, wow.
Thank you so much ilana, I didn’t think anyone was going to respond. It was really kind of you to write such an extensive response, and I’m very grateful that you did. So everything you told me, basically confirms what I came to think the Calendar. That it isn’t an exact siderial calendar, but a relativly sidereal calendar.
I noticed that the 13 moon calendar that’s been floating around the internet is calibrated to have the first day of the first moon in sync with the heliacal rising of the star Sirius. Which right now, means the yearly cycle begins on gregorian 7/26 I didn’t really like the idea of starting the year in mid-summer, so, I decided to syncronize my calendar with the spring equinoxe. So day one of the first month is spring. Which I did simply because spring seems more like '‘the beginning’. Does anyone know of any other calendars that start in spring?

Hey VisionDreamz.

Apologies for not getting back to you earlier. Ilana has done a great job of explaining it all, though. THANKS ilana! The lunar phases are usually tracked alongside the base 13 Moon 28 Day harmonic standard, and because it’s a “13 Moon” Calendar we’re always going to be far more aware of the significance of the moon, than we have been up until now. I believe that this natural rhythm is a great template for channeling group energy and purpose.

Anyway. You asked about the calendar’s used by other cultures who’ve followed the 13 Moon 28 Day Calendar. This is a good link with information about some of the different indigenous 13 Moon calendars: … counts.pdf

The Druids had a 13 Moon 28 Day “Tree” Calendar. I believe every month was named after a different tree

The Maya used the 13 Moon 28 Day Calendar, in the form of the “Tun Uc” (moon count, or count of seven).

The Lakota Indians followed the 13 Moon 28 Day Calendar, by following the pattern of 13 large scales and 28 smaller scales on the Turtle’s back. … turtle.htm … 47-3074223

I was told in a dream that many of the other First Nations of the Americas used a 13 Moon Calendar. As an example, you can find more information on the “13 Moons of the Wsanec People” here: … 3moons.htm

The Polynesians also used a 13 Moon 28 Day Calendar.

I believe evidence of its use can also be found in prehistoric china. It’s really interesting to look at just how common this rhythm is, and how it has evolved all over the world. It’s no surprise however, that no other culture used the same irregular 12 month jumble as we find in the Gregorian Calendar.

The reason we synchronised to July 26, is so we can celebrate the new year as a planet. obviously solstices/equinoxes are still major points of celebration and purification. For those following the calendar, you can also name the solstices/equinoxes after the month in which they are found:

Electric Equinox (in the Electric Moon)
Rhythmic Solstice (in the Rhythmic Moon)
Solar Equinox (this coming Solar Moon)
Crystal Equinox (Crystal Moon)

Hope this helps, but be free to ask more questions too.


PS. I forgot to mention here, but the Ancient egyptians also followed a 13 Moon 28 Day Calendar. I believe it was known as the Calendar of Thoth.

Also it seems important to recognise that the 13 moon Calendar does not aim to displace the use of the Jewish, Muslim or Chinese lunar calendars. Rather it provides a harmonic means by which these differing counts can be synchronised, and unified.