Bahá'í calendar

The Bahá'í calendar, also called the Badí‘ calendar (badí‘ means wondrous or unique), is a solar calendar with years composed of 19 months of 19 days each (361 days) plus an extra period of "Intercalary Days". Years begin at Naw-Rúz, on the vernal equinox, coinciding with March 20 or 21.

The first year is dated from 21 March 1844 CE, the year during which the Báb proclaimed his religion. Years are annotated with the date notation of BE (Bahá'í Era),

The year 174 BE will start at the moment of the vernal equinox in March 2017, meaning that it falls on 20 March 2017.

The Bahá'í calendar started from the original Badí‘ calendar, created by the Báb in the Kitabu'l-Asmá' and the Persian Bayán (5:3) in the 1840s. An early version of the calendar began to be implemented during his time. It used a scheme of 19 months of 19 days (19x19) for 361 days, plus intercalary days to make the calendar a solar calendar. The first day of the early implementation of the calendar year was Nowruz, while the intercalary days were assigned differently than the later Bahá'í implementation. The calendar contains many symbolic meanings and allusions including connections to prophecies of the Báb about the next Manifestation of God termed He whom God shall make manifest.

Bahá'u'lláh, the founder of the Bahá'í Faith, who claimed to be the one prophesied by the Báb, confirmed and adopted this calendar. Around 1870, he instructed Nabíl-i-A`zam, the author of The Dawn-Breakers, to write an overview of the Badí' calendar. In the Kitáb-i-Aqdas (1873) Bahá’u'lláh made Naw-Rúz the first day of the year, and also clarified the position of the Intercalary days to immediately precede the last month. Bahá'u'lláh set Naw-Rúz to the day on which the sun passes into the constellation Aries. Bahá'ís interpret this formula as a specification of the vernal equinox, though where that should be determined was not defined.

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