This week is the last week of 1389 AP (3748 ZRE), i.e. in the Iranian Calendar or Jalali Calendar. Tomorrow night, is Chaharshanbe Soori, The Iranian ancient Fire Festival, and Iranians want to come in the streets and protest again.
There are many differences between Iranian Calendar and Gregorian Calendar and Islamic Calendar. The Iranian calendars are a succession of calendars invented or used for over four millennia in Greater Iran. One of the longest chronological records in human history, the Iranian calendar has been modified time and again during its history to suit administrative, climatic, and religious purposes. The early Zarathushtrians counted their era, the Zarathushtrian Religious Era (ZRE), from Nowruz (vernal equinox) of 1737 BCE. The credit of precisely calculating ZRE goes to an Iranian scholar, the late Zabih Behruz. Right now, we are going through the last days of the last month of 3748 ZRE. The modern Iranian calendar (Solar Hejri / Jalali Calendar) is now the official calendar in Iran. It begins on the vernal equinox as determined by astronomical calculations for Iran. This determination of starting moment is more accurate than the Gregorian calendar because it is synchronized with the vernal equinox year, but requires consulting an astronomical almanac. Its years are designated AP, short for Anno Persico. The Iranian year usually begins within a day of 21 March of the Gregorian calendar. [*]
The earliest evidence of Iranian calendrical traditions is from the second millennium BC, in the age of prophet Zoroaster, and the first fully preserved calendar is that of the Achaemenids. Throughout recorded history, Iranians have been keen on the idea and importance of having a calendar. They were among the first cultures to use a solar calendar and have long favored a solar over lunar and lunisolar approaches. The sun has always been a symbol in Iranian culture and is closely related to the folklore regarding Cyrus the Great himself. Yazdgerd III, the last ruler of the Sassanid dynasty, introduced the final changes to the ancient calendar. The year 632 CE was chosen as the beginning of a new era, and this last imperial Iranian calendar is known as the Yazdgerdi calendar. Before the Yazdgerdi calendar was completed, Muslim Arabs overthrew the dynasty in the 7th century and established the Islamic calendar, a lunar calendar. Umar, the second caliph of Islam, began numbering years in 17AH (638 CE), regarding the first year as the year of Muhammad’s Hijra (emigration) from Mecca to Medina, in September 622 CE. Years of the Islamic calendar are designated AH from the Latin Anno Hegirae.
The solar Jalali calendar was adopted on March 1079 CE in the era of the Seljuk Sultan Jalal al-Din Malik Shah I (for whom it was named), based on the recommendations of a committee of astronomers, including Omar Khayyam . Sultan Jalal commissioned the task in 1073 CE. Its work was completed well before the Sultan’s death in 1092 CE, after which the observatory would be abandoned. In these Calendar, the first six months (Farvardin–Shahrivar) have 31 days, the next five
(Mehr–Bahman) have 30 days, and the last month (Esfand) has 29 days or 30 days in leap years. The name of months are the same as their ancient Persian names:
Spring: 1-Farvardin (Guardian spirits, souls of the righteous) 2-Ordibehesht (Best Truth” / “Best Righteousness) 3-Khordad (Wholeness” / “Perfection)
Summer: 4- Tir (Sirius) 5-Mordad (Immortality) 6-Shahrivar (Desirable Dominion)
Autumn: 7-Mehr (Covenant/Sun) 8-Aban (Waters) 9-Azar (Fire)
Winter: 10-Dey (The Creator, i.e. Ahura Mazda) 11-Bahman (Good Mind) 12-Esfand (Holy Devotion)
The Persian year begins at the first day of Spring Season, i.e. the first day of Farvardin. It’s the best selection for the beginning of the new year. In Iranian Calendar each season begin at the first day of month, and it’s very good. The new year holiday season, or Nowruz Holidays are two weeks, i.e. the first two weeks of Spring. We recommend this sort of calendar to all of you. The New year should begin at Spring, not at Winter or Autumn. The Gregorian calendar, also known as the Western calendar, or Christian calendar, was introduced by Pope Gregory XIII, after whom the calendar was named, by a decree signed on February 1582 CE. You can find the date of today in all calendars here It’s a good website.
[*] To find the corresponding year of Solar Hejri year, subtract 621 or 622 (depending on the time of the year) from a the Gregorian calendar. And to find the corresponding year of Zarathushtrian year, add 1736 or 1737 (depending on the time of the year) to a the Gregorian calendar. And to To find the corresponding year of Zarathushtrian year, add 2359 to a Solar Hejri year.
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