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The Earth Epic Calendar was developed to address the fact that the vast majority of calendars don’t acknowledge the millions and billions of years of Earth history that precede the human race. This calendar also institutes reforms influenced by aspects of other calendars—specifically the Solar Hijri (Iran and Afghanistan), Maya and World Season (proposed by Isaac Asimov) calendars to bring more accuracy and ease of planning compared to the Gregorian Calendar—the calendar currently in use throughout the world.

Older calendars, such as the Jewish Calendar and the Byzantine Calendar claimed the Earth was created sometime in the 6th millenium BC, and in most of Europe, the  Earth was assumed to be that age until the 1600s CE. Earth’s actual age was not well understood until the 20th century. While the Geologic Time Scale does acknowledge the Earth’s actual age, such a time scale is used primarily by scientists, and its time scales are based on climate, geological events, and stratigraphy as opposed to actual units of time.

The average person struggles to grasp the minuscule amount of time humans beings have existed in comparison to the entirety of Earth history. Even when aided by visuals, the quantity of one million--much less one billion--is very hard for the average person to fully comprehend. And given that most calendars are rarely concerned with numbers higher than ten thousand, it could be argued that such calendars present us with a distorted perception of time. They overemphasize the past one to six thousand years—a little more than one millionth of the entire history of the Earth! Given the fact that decisions being made today could potentially undo millions of years of Earth evolution, a sense of scale could help give us perspective on the decisions we make and hopefully help us make better decisions about our Earth.

To address this, the Earth Epic Calendar seeks to bridge this gap by using mostly scales of one hundred (a quantity produced by a ten-by-ten grid) to separate units of time. There are a couple of exceptions to the “Rule of 100’s”--two units of measure starting with the prefix “mil” and the fact that the length of Earth’s year is not easily dividable by one hundred.  The calendar's reliance on units of one hundred make calculations easier. The calendar also sees to link these units of time to developments significant to a human understanding of Earth history. This would help educate people about Earth history in the process. 
The Epic Time Scales

In addition to the time units of day, year, and century that most calendars have, the Earth Epic Calendar adds three larger units know as the Epic Time Scales.

Unit of time Length of time Related to other units
Epoch 25,000 years 25 Millennia
Genesis 2,500,000 years 100 Ages
Eon 250,000,000 years 100 Geneses

Note that each of these units of time are multiples of 25. While it may seem counter-intuitive to use multiples of 25 to calculate these large time units, there are many good reasons to do so.  For example, one Eon ago corresponds roughly to when the first dinosaurs appeared on Earth, and two Eons ago corresponds to the Cambrian Explosion while one Genesis corresponds roughly to when the genus Homo  first appeared on Earth. It is also noteworthy that one Eon is roughly the equivalent of a Galactic Year--that is, the length of time our Solar System takes to orbit the Milky Way.  This 100:1 relationship in time scale between the evolution of the dinosaurs and Homo  helps us better understand our relationship with the Earth. With the Earth being approximately 4.54 billion years old (give or take 40 million years), this translates to 18 Eons.  

The Epoch time unit has its own significance. Twenty five thousand years (or 25 millenia) is close in length to an Earth cycle known as the Axial Precession. This phenomenon, discovered by the ancient Greeks and possibly the ancient Egyptians, Babylonians, and Mayans as well, represents a slow change in the position of the tilt of Earth's axis. As a result, it appears to us that the stars and constellations are moving backwards relative to Earth. Astrologers understand this cycle, with many arguing that the world is about to precess from the Age of Pisces to the Age of Aquarius. A full Axial Precession, as seen from Earth, appears to go through all twelve signs of the zodiac.

The current epoch is dated from 9701 BCE, or 11,700 years before the year 2000 CE. This is regarded by the International Commision on Stratigraphy as the beginning of the Holocene, when the last glacial period ("Ice Age") ended and human civilization began to evolve. The implications of an epoch being 25,000 years in length means that human civilization is less than halfway through the current epoch. Perhaps that might suggest that human civilization has a lot more evolving to do in order to become truly "civilized." The degree to which we threaten all life on Earth due to modern consumer lifestyles and the threat of nuclear war is a testament to how much more evolving we as a species must do.

The Calendar Time Scales: Millenia, Years, Quarters, and Days

While the Epic Time Scales makes it easier to track events in the distant past and far future, the method for subdividing the years improves on the Gregorian Calendar by introducing reforms influenced by the Solar Hijri, Mayan and World Season calendars. These reforms improve the accuracy of the calendar over the Gregorian Calendar and make it easier to subdivide and plan the year.

The Millenium and Year are, of course, the same lengths as they are in the Gregorian and many other calendars.  As is true of modern Gregorian usage, the choice of whether to use the millenium, century or year depends on what is most convenient for the purpose of communicating.   

The length of the year—365 or 366 days—provides a challenge for continuing the “rule of one hundreds.” But dividing the year into Quarters, as done in the World Season Calendar, produces units of 91-92 days each, which is close to one hundred and therefore can be said to continue the rule of “one hundreds.”  Note also that 100,000 quarters equal one epoch. In fact, were it not for the length of time the Earth takes to rotate around the Sun,  the rule of “one hundreds” would stay mostly consistent.
Calendar Time Scales

Besides this, there are other advantages to using quarters over months:  1) Easier to identify the time of the year, as the quarters align closely with the equinoxes and solstices experienced by the entire planet, 2) Easier to plan longer term, as the quarters are exactly or almost exactly thirteen weeks, and, 3) Easier to sub-divide.

Time unit Length of Time
Millenium 1,000 years or 100,000 quarters
Year 4 quarters or 365 days
Quarter 91-92 days

Like the World Season Calendar, the new year starts around of the time of the Winter Solstice in the Northern Hemisphere. Unlike the World Season Calendar however, the new year doesn’t always start on December 21. Instead, the Earth Epic Calendar determines the date of the new year using a method similar to the observation-based Solar Hijri Calendar That system begins the new year at the midnight closest to (before or after) the Spring Equinox. In the Earth Seasons Calendar, the new year begins at the midnight (UTC) closest to the Winter Solstice.

Leap years are not determined by a specific formula, but by the actual number of days between the Winter Equinoxes. Sometimes the days number 366, and other times 365. Most of the time, leap years occur every four years, but sometimes the interval is five years. This observation-based model puts the Earth Epic Calendar up with the Solar Hijri calendar as the most accurate solar calendar today.  The year 11.719 (2018-19 in the Gregorian Calendar) is a leap year.

Quarters by default are 91 days and roughly aligned with the Western seasons of winter, spring, summer, and fall. The length of these quarters makes planning easier. By seeing thirteen weeks at once on a calendar page rather than four or five, scheduling further into the future becomes easier. Given that 91 x 4 = 364, it needs to be determined where to put the 365th day and the leap day. Again, the Solar Hijri calendar currently provides the most accurate model—even more accurate than the Earth Epic Calendar itself--as the longest months of the year currently occur during the Northern Hemisphere spring and summer. The Earth Epic calendar does, however, add the 365th day and the leap year day to the months most closely aligned with the longest astronomical season—in this case the end of summer for the 365th day and the end of spring for the leap day. This is the compromise the Earth Epic Calendar makes between alignment of the seasons and a symmetrical, easy to plan calendar. In about five thousand years, as the Earth precesses through the Axial Precession cycle, the Earth Epic calendar will adjust itself so that the 365th day is added to the end of autumn, with the leap day being at the end of summer.

Unlike Gregorian months and years, the numbered days of the Earth Epic quarters and years begin with 0 instead of 1. This is similar to parts of the Maya Calendar system. This is because the Gregorian calendar uses counting numbers in its months and years while the Earth Epic calendar uses scalar numbers that can be sub-divided. For the Earth Epic Calendar, this is done because any unit of time can be subdivided, and even represent units less than 1. As such, the number of the day of any quarter represents the number of days already completed. The midnight after Day 0 begins Day 1 because one day in the quarter has at that point been completed. This is already done with the time of day--1:00 a.m. represents one hour completed after midnight. This is true of every other unit in the Earth Epic Calendar. The concept of zero as a number didn’t exist in European society when the Julian Calendar was created, and even the Gregorian calendar continues to have 1 AD follow 1 BC. A relatively new international standard,  ISO 8601 has changed this but is not widely used by citizens.

The names of the quarters should be determined by local cultures, rather than being imposed on the entire world. But for international communication, the Earth Epic Calendar uses the names Northlight, Southlight, Eastlight and Westlight. Northlight and Southlight correspond to the hemisphere at which the sun is at its most direct angle. As such, the quarter starting with the December solstice is named Southlight and the quarter starting with the June Solstice is Northlight. The names Eastlight and Westlight are more metaphorical—symbolizing the path of the sun from East to West over the course of the day.  By applying the metaphor to the year,  Eastlight starts around the March Equinox and Westlight starts around the September Equinox.  


The Earth Epic Calendar does not officially have the seven day week as part of the calendar, but at least for the short term is using the seven-day week because the world’s schedule currently revolves around weeks. Islam, Judaism, and Christianity also rely on the seven day week in order to observe their respective sabbaths, established on Friday, Saturday and Sunday respectively.  Previous efforts in the 20th century to adopt a world calendar that deviated from a seven day week were met with strenuous objections from representatives of these three religions because of the belief that the sabbath must be every seven days. The Earth Epic calendar defaults to local traditions when it comes to the names of the days of the week.

It will be up to future generations to decide whether to continue with this practice. One option might include dividing the quarter into nine ten-day weeks, so that the last digit of the day also determines the day of the week.

The Decimal Time Scales

The time system in the Earth Epic Calendar is itself somewhat unique and new though not unprecedented. This calendar uses decimal time, which was used in China, attempted during the French Revolution and introduced at other times since then.

The Decimal Time Scales   

Unit of time Equivalent length
1 day 1,000 millidays (mday)
1 milliday 100 secs or 1 minute, 26.4 seconds
1 sec 0.864 seconds

The Earth Epic Calendar designates a Milliday as one thousandth of a day, and a Sec as one one-hundredth of a milliday. This is the second time unit that uses an interval of one thousand, and like the millenium, has the mil- prefix to avoid confusion. A milliday is a little more than a minute, and a sec is a little bit less than a second. tronomical seasons vary in length between 88 and 93 days, and will change as the Earth preceeds through the Axial Precession cycle.

The lengths of the quarters in the Earth Epic Calendar don’t align precisely with the seasons because the Earth Epic Calendar values symmetry of the year and ease of planning over alignment with actual seasons.

Expressing the time in millidays would give a three digit number between 000 and 999 as a the time, with the digits representing one-tenth, one-one hundredth, and one-thousandth of a day, respectively.  So 623 millidays and 77 secs would read like this: 623.77 mday.  

Here are simple guides for converting between sexigesimal and decimal time:

Decimal time Sexigesimal Time

Sexigesimal Time

Decimal time
0 mday 12:00 am 12:00 am 0 mday
50 mday 1:12 am 1:00 am 41.67 mday
100 mday 2:24 am 2:00 am 83.33 mday
150 mday 3:36 am 3:00 am 125 mday
200 mday 4:48 am 4:00 am 166.67 mday
5:00 am 208.33 mday
250 mday 6:00 am 6:00 am 250 mday
300 mday 7:12 am 7:00 am 291.67 mday
350 mday 8:24 am 8:00 am 333.33 mday
400 mday 9:36 am 9:00 am 375 mday
450 mday 10:48 am 10:00 am 416.67 mday
11:00 am 458.33 mday
500 mday 12:00 pm 12:00 pm 500 mday
550 mday 1:12 pm 1:00 pm 541.67 mday
600 mday 2:24 pm 2:00 pm 583.33 mday
650 mday 3:36 pm 3:00 pm 625 mday
700 mday 4:48 pm 4:00 pm 666.67 mday
5:00 pm 708.33 mday
750 mday 6:00 pm 6:00 pm 750 mday
800 mday 7:12 pm 7:00 pm 791.67 mday
850 mday 8:24 pm 8:00 pm 833.33 mday
900 mday 9:36 pm 9:00 pm 875 mday
950 mday 10:48 pm 10:00 pm 916.67 mday
11:00 pm 958.33 mday

Expressing the date and time

As is true now, how the date is written or expressed depends on what you want to communicate or why.  It makes sense to highlight what is the most important.  The Earth Epic Calendar has nine different units of time to choose from.

Fundamentally, the expression of time is separated by decimal point.  Here is an example of a date in its most fundamental expression. This means 18 Eons, 16 Geneses, 12 Epochs, 117 Centuries, 16 years, the quarter of Southlight, Day 22, 500 Millidays and 66 Secs estimated since the formation of the Earth.

This, of course, is a little bit difficult to read, so breaking up the expression between the Epic, Calendar and Decimal Time Scales is a good first step.

(18.16.12) 11.716 Southlight 22, 500.66 mday

The Epic Time Scales are always expressed by three two digit numbers.  These three numbers will remain the same until we reach Epoch 13, which will be around December 21, 15,299 CE.  So these scales will only likely be used in formal expressions of the date (think about how dates are written out on diplomas, for example) or when referring to dates in eons, geneses and epochs in the past or future—such as earth scientists, archaeologists, et cetera. 

The question of whether to use the millenium in the date expression depends on what you wish to communicate. Which expression below is the most practical?  It’s up to you, and it partially depends on the context.  

11.716 Southlight 22
716 Southlight 22

If you are comparing dates across centuries since 1300 CE—that is, the beginning of our current Millenium 11 EE—the three digit year would be the most effective.  See how much easier it is to distinguish between the three-digit years compared to the five-digit years.

Event Gregorian Year EE 3-digit Year EE 5-digit year
Beginning of Black Death 1340 40 11.040
Fall of Constantinople 1453 153 11.153
Voyages of Christopher Columbus 1492 192 11.192
Introduction of Gregorian Calendar 1582 282 11.282
War of the Three Kingdoms Begins 1639 339 11.339
Bacon's Rebellion 1676 376 11.376
Glorious Revolution 1688 388 11.388
Acts of Union, Founding of United Kingdom 1707 407 11.407
American Declaration of Independence 1776 476 11.476

If, however, you are comparing dates across centuries that cross a millenium boundary, then you’ll want to include the millenium.  Note that when doing so, you must indicate the millennium even when in Millennium 0, so that you don’t confuse the approximate date the earliest known walled city of Jericho was built –expressed as 0.700—with 2000 CE—which can be expressed in this millennium as either 700 or 11.700.

The Earth Epic Calendar reflects our current understanding of the Earth and passage of time. As such, it is a big step forward from the predominantly religious calendars that have dominated up until this point.  It addresses religious imperialism by being independent of any religion that would seek to declare a monopoly on truth. It addreses cultural imprerialism through its independence of any specific culture and by permitting local cultures to name the quarters as appropriate for them.  It is the first calendar to take into account time on Earth before the genesis of the human race and, as such,  represents an important shift away from a human-centric point of view to account for the Earth as a whole life system. 

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