32 Facts About Hebrew calendar

1.

Present Hebrew calendar is the result of a process of development, including a Babylonian influence.

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2.

Until the Tannaitic period, the Hebrew calendar employed a new crescent moon, with an additional month normally added every two or three years to correct for the difference between the lunar year of twelve lunar months and the solar year.

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3.

Biblical references to the pre-exilic Hebrew calendar include ten of the twelve months identified by number rather than by name.

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4.

Accuracy of the Mishnah's claim that the Mishnaic Hebrew calendar was used in the late Second Temple period is less certain.

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5.

Between 70 and 1178 CE, the observation-based Hebrew calendar was gradually replaced by a mathematically calculated one.

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6.

Later writers, such as Nachmanides, explained Hai Gaon's words to mean that the entire computed calendar was due to Hillel b Yehuda in response to persecution of Jews.

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7.

Furthermore, two Jewish dates during post-Talmudic times are impossible under the rules of the modern Hebrew calendar, indicating that its arithmetic rules were developed in Babylonia during the times of the Geonim .

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8.

Except for the epoch year number, the Hebrew calendar rules reached their current form by the beginning of the 9th century, as described by the Persian Muslim astronomer Muhammad ibn Musa al-Khwarizmi in 823.

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9.

Al-Khwarizmi's study of the Jewish Hebrew calendar describes the 19-year intercalation cycle, the rules for determining on what day of the week the first day of the month Tishri shall fall, the interval between the Jewish era and the Seleucid era, and the rules for determining the mean longitude of the sun and the moon using the Jewish Hebrew calendar.

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10.

Seventh day, Shabbat, as its Hebrew calendar name indicates, is a day of rest in Judaism.

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11.

Accordingly, the basic Hebrew calendar year is one of twelve lunar months alternating between 29 and 30 days:.

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12.

Since the adoption of a fixed calendar, intercalations in the Hebrew calendar have been assigned to fixed points in a 19-year cycle.

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13.

The Hebrew calendar rules have been designed to ensure that Rosh Hashanah does not fall on a Sunday, Wednesday or Friday.

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14.

In Hebrew calendar there are two common ways of writing the year number: with the thousands, called, and without the thousands, called .

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15.

Hebrew calendar included all the rules for the calculated calendar and their scriptural basis, including the modern epochal year in his work, and beginning formal usage of the anno mundi era.

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16.

Jewish Hebrew calendar has several distinct new years, used for different purposes.

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17.

Jewish Hebrew calendar is based on the Metonic cycle of 19 years, of which 12 are common years of 12 months and 7 are leap years of 13 months.

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18.

However, there is another rule which not only tells whether the year is leap but gives the fraction of a month by which the Hebrew calendar is behind the seasons, useful for agricultural purposes.

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19.

At the innovation of the sages, the Hebrew calendar was arranged to ensure that Yom Kippur would not fall on a Friday or Sunday, and Hoshana Rabbah would not fall on Shabbat.

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20.

Annual calendar of a numbered Hebrew year, displayed as 12 or 13 months partitioned into weeks, can be determined by consulting the table of Four gates, whose inputs are the year's position in the 19-year cycle and its molad Tishrei.

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21.

The in Hebrew calendar letters are written right-to-left, so their days of the week are reversed, the right number for and the left for.

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22.

Furthermore, the seasonal drift of the rabbinic Hebrew calendar is avoided, resulting in the years affected by the drift starting one month earlier in the Karaite Hebrew calendar.

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23.

Also, the four rules of postponement of the rabbinic Hebrew calendar are not applied, since they are not mentioned in the Tanakh.

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24.

Calculation of the Samaritan Hebrew calendar has historically been a secret reserved to the priestly family alone, and was based on observations of the new crescent moon.

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25.

Epoch of the Samaritan Hebrew calendar is year of the entry of the Children of Israel into the Land of Israel with Joshua.

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26.

Many of the Dead Sea Scrolls have references to a unique Hebrew calendar, used by the people there, who are often assumed to be Essenes.

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27.

Year of this Hebrew calendar used the ideal Mesopotamian Hebrew calendar of twelve 30-day months, to which were added 4 days at the equinoxes and solstices, making a total of 364 days.

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28.

Furthermore, the molad interval determines the calendar mean year, so using a progressively shorter molad interval would help correct the excessive length of the Hebrew calendar mean year, as well as helping it to "hold onto" the northward equinox for the maximum duration.

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29.

The Hebrew calendar, which is a tradition with great importance to Jewish practice and rituals was particularly dangerous since no tools of telling of time, such as watches and calendars were permitted in the camps.

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30.

The keeping of a Hebrew calendar was a rarity amongst prisoners and there are only two known surviving calendars that were made in Auschwitz, both of which were made by women.

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31.

Early Zionist pioneers were impressed by the fact that the Hebrew calendar preserved by Jews over many centuries in far-flung diasporas, as a matter of religious ritual, was geared to the climate of their original country: the Jewish New Year marks the transition from the dry season to the rainy one, and major Jewish holidays such as Sukkot, Passover, and Shavuot correspond to major points of the country's agricultural year such as planting and harvest.

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32.

Accordingly, in the early 20th century the Hebrew calendar was re-interpreted as an agricultural rather than religious calendar.

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