Ancient Babylonian Calendar

Additional months in the of the ancient Babylonian calendar were inserted by order of the authorities. Known is one such decree, published by Hammurabi around 1760 BC."Since the year has a defect, let the month that is now beginning, will be called the second Ululu, and relying in Babylon on the 25th day of the month, Tashritu, let it be delivered on the 25th day of the month of Ulula the second."

With such edicts, the calendar was regulated up to the 5th century. BC.e. During this time, the Babylonian kingdom was repeatedly attacked by its neighbors, mainly the Assyrians;about 729 BC.e.it for a whole century was completely deprived of independence, the city of Babylon itself in 689 BC.e.was completely destroyed. However, less than a hundred years, he again shone in all its greatness. The leading force in this revived state was the Chaldean tribes who came here. In 609 BC.e. Assassins were killed under the blows of the already strong Babylonian state, in 597 BC.e. The Babylonians captured Palestine with its capital, Jerusalem. But next to it a new force was raised - Persia, and already in 539 BC.e. Babylon was conquered by the Persian king Cyrus. Two hundred years later Alexander the Great comes here and finds his death here. The territory of the former Babylonian kingdom becomes part of the Seleucid Empire. ..

For nearly two millennia, Babylonia was one of the richest countries in the world, a hotbed of science and culture. Astronomy was a great development here. Observations of celestial bodies were carried out from the upper platforms of multistage towers( ziggurats), which had five or seven floors and were simultaneously temples. Around 700 BC.e.in Babylon was compiled a textbook on astronomy( "Mul-apin").From the point of view of the question of the calendar, it is very important that it contained information on the moments of heliacic( rhythmically repeated throughout the solar( !) Year) sunsets of individual stars. As the analysis has shown, some of these tables were compiled approximately 3000 years BC.e. And this means that the Babylonian astronomers had all the data in order to make insertions of the 13th month not arbitrarily, but in accordance with the position of the Sun on the ecliptic.

This is confirmed by the following entry on one of the plates: "If on the first day Nisanu Moon is in conjunction with the Pleiades, the year is simple;if on the third day Nisan Luna in conjunction with the Pleiades, a full year [13 months]. "It's clear. For two days the Moon moves in the sky by 24 ° relative to the Sun, 4 - by the distance the Sun passes almost a month. In March, at the moment of incomprehension at the latitude of Babylon, the Moon in relation to the Sun is approximately 8 ° to the east. And if it is in conjunction with the Pleiades, then the Sun at the same time is in the constellation of Aries, not far from the modern border with the constellation of Taurus, where about 3000 years ago and was the point of the vernal equinox. If the Moon came into contact with the Pleiades on the third day, then the distance of the Sun from the point of the vernal equinox exceeds 20 °.Lunar year from 12 months shorter than solar for 11 days, so by the end of the last, 12th month this distance will be more than 30 °, and the new year would begin too soon. The insertion of an additional month delays the coming of the new year for 30 days. During this time, the Sun significantly reduces its distance from the point of the vernal equinox or even goes for it.

As can be seen from cuneiform documents, approximately from 600 BC.e. In the Babylonian calendar, octaetheride was used with insertion months in the 2 nd, 5 th and 8 th years. Since the end of the IV century. BC.e. The calendar is regulated by a 19-year cycle, the discovery of which is about 380 BC.e.is associated with the name of the astronomer Cidenas. In this case, the 1st day of the 1st Nisan is kept near the spring equinox. There is evidence that the Babylonian astronomers have also verified their calendar with the heliacal rise of the Capella - a star and a Voznichy.

It's no wonder therefore, that already about 1100 BC.e. The Babylonian calendar was borrowed by the Assyrians, and the peoples who fell under the rule of Babylon, in particular the Jews, began to use it.