The Kazakh Nomad Calendar Software

Software for converting between
dates in the Kazakh Nomad Calendar and
dates in the Gregorian Calendar

Download of this program has been temporarily suspended

Very Brief Historical Background

For thousands of years ethnic Kazakhs roamed the steppes of what is now Kazakhstan, the 9th largest country in the world. They were nomads, who lived by grazing sheep and goats. Their mode of transport was by horse and camel, and they lived in moveable round tents call yurts (at the apex of which was a hole through which the Moon and stars could be observed). The language of the nomads had no written form, but nevertheless they managed to develop a remarkable lunisolar calendar based on the relation in the sky between the Moon and the Pleiades star cluster, of which the central and brightest star is called "Alcyone".

Principles of the Nomad Calendar

In comparison with the Chinese lunisolar calendar, the principles underlying the Kazakh Nomad calendar are quite simple. They were stated by Kaldarkhan Kambar, a descendant of the ancient Kazakh nomads, in an article about the Maya Calendar (published on this website) where he says:

The star calendar, based on the sidereal cycle of the Moon, in practice is used very seldom. It is also the most ancient calendar. Such calendars under the name togys (from kazakh togysu meaning “to intersect’ [occultation]) were used by Kazakhs. The beginning of months coincides with the moment when the Moon passes the Pleiades and the names of months correlate with lunar phases. As the difference between the synodic and sidereal cycles of the Moon is about 2 days, each subsequent meeting of the Pleiades and the Moon occurs on a lunar phase that is 2 days earlier than the previous lunar phase.

Stated more precisely, a month in the Kazakh Nomad Calendar begins on the nychthemeron (the midnight-to-midnight local time period for the Kazakh nomads) during which the Moon (appearing to travel in the sky from east to west) attains the same right ascension (to use a modern astronomical term) as the (stationary) Pleiades (or, for exactness, the central star Alcyone). If, at this time, they have the same or similar declination, so that the Moon appears to cover the Pleiades, then we have what is called an "occultation". There are years-long periods when an occultation occurs each month, followed by years-long periods when there is no occultation (but the Moon still passes the Pleiades, above or below).

The Role of the Polar Star

Astute readers will now ask: Since the nomads (presumably) did not have the modern astronomical concepts of celestial sphere and right ascension, how did they know when the Moon attained the same right ascension as the Pleiades? Especially because this event does not occur when, from the point of view of an observer on the ground, the Moon is exactly above or below the Pleiades.

The nomads understood that (in modern language) the Moon and the Pleiades had the same right ascension when the line joining them could be extended northward to reach the pole star (our "Polaris", which the nomads called the "Iron Stake"). Below is a screenshot from the Stellarium planetarium program (the blue lines mark right ascension and declination) showing the view of the night sky from Almaty at 20:50 on October 26, 2018, when the right ascension of the Moon is the same as that of the Pleiades, namely, 3h46m58s. Although the Pleiades is above and to the left of the Moon, as observed from the ground (the horizon is shown at the bottom), the Pleiades can be seen to lie on an imaginary line joining the Moon and Polaris.

The time of the passing of the Pleiades by the Moon (marking the first day of the month) is less easily determined when the event occurs during daylight, when the Pleiades is not visible. As the old month drew to a close, the nomads observed the Pleiades and the Moon at night, when both were visible, and if in the early hours of some day (nychthemeron) the Moon had not yet reached the Pleiades, and in the late hours (before midnight) it had passed the Pleiades then, although the exact alignment (that is, equal right ascension) occurred during the daylight hours, these two observations were sufficient to establish that this nychthemeron was the first day of the month.

Now, of course, the time of the event can be calculated exactly (by simulation of the motion of the Moon), thus providing a firm astronomical underpinning to the Nomad Calendar.

The Nomad Calendar is a Solilunar Calendar

Because the sidereal period of the Moon — the time it takes to return to the same position (more exactly, same right ascension) in the sky, such as the position of the Pleiades — is approximately 27.3 days, such a sidereal month, when measured in days, always has either 27 or 28 days. The month was named by the Kazakh nomads according to the phase of the Moon at the time of the passage.

The Kazakh nomads developed their calendar for meteorological and agricultural purposes. Thus they needed a seasonal calendar. They managed to do this by segmenting the sequence of sidereal months into seasonal years, where a year begins on the day (nychthemeron) at which a crescent moon first becomes visible following a dark moon. (A dark moon occurs when the Moon is exactly between the Earth and the Sun and is thus invisible.) It turns out that a year in the Kazakh Nomad Calendar always has either 13 or 14 (sidereal) months, a 13-month year (almost) always has either 355 or 356 days, and a 14-month year (almost) always has either 382 or 383 days.

Like the Chinese, the Kazakh nomads named years by using a cycle of 12 animal names. In order they are "Mouse", "Cow", "Leopard", "Hare", "Wolf", "Snake", "Horse", "Sheep", "Monkey", "Hen", "Dog" and "Boar". The sequence of years was thus divided into 12-year periods

Extensions to the Traditional Calendar

It is uncertain whether the Kazakh nomads distinguished between one 12-year cycle and those preceding and succeeding it. In order that dates in the Nomad calendar should designate days unambiguously, it is necessary to distinguish those cycles, and this is done in the present digital implementation of the calendar.

This could be done by a system of numbered cycles each containing a certain number of subcycles. It is, however, simpler to number the cycles sequentially from a chosen base year, with that year being designated a Mouse year. (This is the system used in the software described here.) This allows us to write a Nomad Calendar date in the short form:

{cycle-number}-{animal name of year}-{month}-{day number}

where {month} is either a numeral or the name of a moon phase (in the style of the nomads, as will be explained below).

If we choose -3680 (that is, 3681 BCE) as the base year then Cycle #1 consists of the years -3680 through -3699 (that is, 3681 BCE through 3700 BCE). If the cycles are so numbered, then the 12-year period from 2008 CE through 2019 CE is Cycle #474.

The Kazakh Nomad Calendar Software

• Converts a Gregorian Calendar date to a Nomad Calendar date.
• Converts a Nomad Calendar date to a Gregorian Calendar date.
• Displays an entire Nomad Calendar month with dates in both calendars (plus the Julian day numbers of the days).
• Lists all years in a particular cycle along with the Gregorian start dates of each month in each year, plus the number of days in each month.

When the software starts up it displays the current month in the Nomad Calendar, for example:

Conversion of a Kazakh Nomad date to and from a Gregorian date is easily done. After setting a Nomad date (or converting from a Gregorian date) clicking on the "Display Nomad Calendar date" produces what is shown above. For an explanation of nomad month names, see below.

Clicking on the "List Months in Cycle" button produces a list of the years and their months in the specified cycle (the width of the window can be reduced by dragging the right border inward). "JDN" is the Julian day number. "Age of Moon" is the number of days since the occurrence of the dark moon at the start of the month. Here is a sample screenshot:

This software has been validated by comparison with listings of the dates of the starts of the months in all Nomad Calendar years from the Monkey Year of Cycle 473 (2004-2005 GC) to the Snake Year of Cycle 474 (2025-2026 GC) supplied by Kaldarkhan Kambar based on his use of online star maps (such as this one). There are sometimes slight differences for these dates, due to the different methods used, but the difference is at most one day.

Kazakh Nomad Calendar Month Names

The months were not numbered in the traditional nomad calendar, instead they were named as follows:

The "togys" number is (very) approximately the number of days of the age of the Moon on the 1st day of the month. The year begins with the month whose 1st day occurs when the Moon passes the Pleiades immediately after a dark moon (when the crescent Moon first becomes visible), so at that time the age of the Moon is approximately 1 day. When the 2nd month begins, approximately 27 days later, the Moon has not yet completed the lunation (namely, the lunation which began one month earlier), and its age is something like 27 days. With each successive month the age of the Moon decreases by about 2 days, and the month names decrease to "3 togys", the name of the final month of the year.

Much more information about the Nomad Calendar (called "Togys esebi" in Kazakh) can be found in Chapter 3 of K. A. Kambar's book National Calendar of Kazakhstan, at present available only in the Kazakh language

The Nomad Calendar as a Scheduling Aid

Each month in the Nomad Calendar has either 27 or 28 days. Thus, unlike months in the Gregorian Calendar, every month can be partitioned into three 7-day weeks plus a final week of either 6 or 7 days. This makes scheduling events much easier than with the Gregorian Calendar, whose months consist mostly of four 7-day weeks plus 2 or 3 days more. Moreover, the first day of a Gregorian month can have any weekday name, and for a particular month the weekday name of the first day of the month varies from year to year. It is thus difficult to select and announce dates for events (months or even years in advance) which should begin on a particular day of the week.

As in the Gregorian Calendar, the first day of the month in the Nomad Calendar does not always fall on the same day of the European week. The screenshot above shows this clearly.

Regularity, however, can be obtained simply by using a different system of seven weekday names, names of stars which are among the brightest in the night sky, namely, "Arcturus", "Betelgeuse", "Canopus", "Deneb", "Elnath", "Fomalhaut" (these run from "A" to "F") plus "Sirius". The name of a particular day in a Nomad month is then easy to remember, since the sequence is the same for each of the four weeks. For example, "Canopus" is the name of the 3rd day in each week, thus the name of Days 3, 10, 17 and 24. A "Sirius" day always occurs on Days 7, 14 and 21, and on Day 28 in a month with 28 days. Thus for scheduling purposes (e.g., the semesters, courses and lectures at an educational institution) this calendar is vastly superior to the Gregorian Calendar.

For use in Western countries the nomad month name can be replaced by the number of the month, so dates would be of the form:

{cycle-number}-{animal name of year}-{month number}-{day number}

as in "475-Mouse-2-24 KN" (= "2020-06-14 GC"). Replacing the animal year name by its number would give the purely numerical (and computer-friendly) form of the date, "475-01-02-24 KN".

Date Range

In principle, for each Gregorian date from 3681 BCE onward there is a unique corresponding date in the Nomad Calendar. However, the earliest Gregorian date that can be converted using this software is April 16, 1600 (= 440-Mouse-1-1 KN), and the latest is December 24, 2099 (= 481-Sheep-8-25 KN). As we move further into the 21st Century (and astronomical research continues) the "latest date" will probably move forward and remain well ahead ahead of the current date.

The reason for this limitation is that the calculation of the exact time of the Moon's overtaking of the Pleiades requires the determination of the lunar longitude and latitude at a specific time (to within 1 minute). Or rather, an estimate of these values, because the position of the Moon is increasingly uncertain prior to 1600 CE and after 2100 CE.