The Mayan and Julian Calendar The Mayan calendar, in its full glory, is probably the most complicated calendar based on integer arithmetic that has ever existed. While lunar and lunisolar calendars do exist that are very complex, most of them are based on observation, as in starting a month when the moon is in a particular stage, or on floating point calculations that for all practical purposes simply replace such observation. The Maya did not have algebra, but they had an enormous advantage over many calendar-builders in the old world in that they invented zero (Kelley).

The Mayan calendar is comprised of many elements: The tzolkin, a 260-day interlocking cycle of 13 numbers and 20 day names; The haab, a 365-day year, also known as the vague year since the haab drifts in relation to the seasons. This is a linear cycle of 18 months of 20 days, plus a terminal 5-day month. The Maya made no attempt to synchronize the seasons and the haab, unlike the Gregorian calendar in widespread use today; The Long Count, an exact count of days from a zero point, usually referenced to Wed Sep 8, 3,114 BC (Julian Style).

This assumes a Correlation Constant of 584285, the revised GMT correlation; A perpetual cycle of 9 Lords of the Night; An 819-day cycle of 4 colors and 4 directions and their corresponding gods; Numerous cycles and ritual periods. (Kelley) In the year 46 BC, the Greek Sosigenes convinced Julius Caesar to reform the Roman calendar to a more manageable form. At this time, Julius also changed the number of days in the months to achieve a 365-day year. In order to catch up with the seasons, Julius Caesar also added 90 days to the year 46 BC between November and February (Vardi 1991, p.238).

### The Essay on Modern Day Plague Year 2000

Modern Day Plague Argument: Mankind has become too dependent on computers, and we as a society are covering up our errors and not facing the facts, to avoid panic. About four years ago, a new "pop" headline came hot of the press rumoring something about home computers having problems when the year 2000 hit. "The year 2000, that's six years away," people thought. Many believed in six years it would ...

The Julian calendar consisted of cycles of three 365-day years followed by a 366-day leap year. Around 9 BC, it was found that the priests in charge of computing the calendar had been adding leap years every three years instead of the four decreed by Caesar (Vardi 1991, p.239).

As a result of this error, no more leap years were added until 8 AD. Leap years were therefore 45 BC, 42 BC, 39 BC, 36 BC, 33 BC, 30 BC, 27 BC, 24 BC, 21 BC, 18 BC, 15 BC, 12 BC, 9 BC, 8 AD, 12 AD, and every fourth year thereafter (Tondering).

The average length of a year in the Julian Calendar is 365.25 days (one additional day being added every four years).

This is significantly different from the real length of the solar year. However, there is uncertainty among astronomers as to what the length of the solar year really is (see Simon Cassidys Error in Statement of Tropical Year).

The main competing values seem to be the mean tropical year of 365.2422 days (mean solar days) and the vernal equinox year of 365.2424 days. The difference of the length of the Julian calendar year from the length of the real solar year is thus 0.0078 days (11.23 minutes) in the former case and 0.0076 days (10.94 minutes) in the latter case. The Roman date-keepers initially misunderstood Caesars instructions concerning the new calendar (according to Macrobius), and erroneously held every third year, rather than every fourth year, to be a leap year. There is some dispute as to exactly which years from 43B.C. through to 8A.D.

were actually leap years, but a reconstruction which is consistent with the available evidence is that every third year following 43B.C. (i.e. 40B.C., 37B.C., etc.) was a leap year, until 10B.C., after which, according to this hypothesis, Augustus Caesar (Julius Caesars successor) suspended leap years, reinstating them with the leap year of 4A.D. As one can see, both Mayan and Julian Calendars are truly amazing systems of time keeping. The Mayan Calendar still leaves scientists wonder its algebraic accuracy, and the Julian calendar became a forebear of the calendar, used by nearly all people in the modern world. Even though, these two calendars are somewhat different, they have such similar as number of days 365, and a zero point.

### The Essay on 260 Day Maya Calendar Days

The Maya Calendar The Maya calendar in its final form probably dates from about the 1 st century B. C. It is extremely accurate, and the calculations of Maya priests were so precise that their calendar correction is 10, 000 th of a day more exact than the standard calendar we use today. They used 20-day months, and had two calendar years: the 260-day Sacred Round, or tzolkin, and the 365-day Vague ...

The differences are the number of days in a month, number of month and a presence of a leap year in the Julian calendar. Works cited: Kelley, David H., The Maya Calendar Correlation Problem, in Kolata, Alan L., and Richard M. Leventhal, eds., Civilization in the Ancient Americas, University of New Mexico, Albuquerque, 1983, p. 157. Tondering, C. Frequently Asked Questions about Calendars. http://www.tondering.dk/claus/calendar.html. Vardi, I. The Julian Calendar.

3.5.1 in Computational Recreations in Mathematica. Reading, MA: Addison-Wesley, pp.44 and 238-240, 1991..