Aban — month 8 of the Persian year
The eighth month of the Solar Hijri year, called Aban in Iranian usage and Aqrab in Afghan usage, runs 30 days in autumn.
The month at a glance
- Month number
- 8
- In Iranian usage
- Aban
- In Afghan usage
- Aqrab, or borj 8
- Length
- 30 days
- Gregorian window
- October 22 to November 22
This month shares its Afghan name with a zodiac sign. What the tradition carries for the sign is on the sign's own page; this page is about the month.
Aban and Aqrab: one month, two naming systems
Month 8 of the Solar Hijri calendar is called Aban in Iranian usage and Aqrab in Afghan usage. These are two names for the same month of the same calendar. Neither is a nickname for the other.
In Afghan usage the traditional borj names are the month names, and a month is very often referred to simply by its number. Borj 8 is this month: Aqrab. If you came here after typing that number, this is the month you were looking for.
Only the names differ between the two systems. The month boundaries are the same, the lengths are the same, and the leap rule is the same. A date written in one naming system falls on exactly the same day as the same date written in the other, so nothing needs converting between Iranian and Afghan usage beyond swapping the name.
Where the eighth month sits in the year
Aban, or Aqrab, is the eighth month of the Solar Hijri year, and it falls in autumn. The month before it is Mehr, called Mizan in Afghan usage. The month after it is Azar, called Qaws in Afghan usage.
It runs 30 days, every year. Its length does not shift in a leap year, and it is the same 30 days under either naming system. The leap day of this calendar belongs to Esfand, the last month, which is the one month whose length varies; Aban is unaffected by it.
Why its Gregorian dates shift from year to year
The lengths of the Solar Hijri months are set by the calendar's own rule, but the start of the year is not. The year begins at the vernal equinox, an astronomical moment that does not fall on the same Gregorian day each time. Every month after it inherits that small drift, so the Gregorian date on which Aban begins is determined by the equinox rather than fixed by choice.
The movement is narrow and predictable rather than loose. Over the documented window of 101 consecutive Persian years, 1329 to 1429, corresponding to the Gregorian years 1950 to 2050, this month has begun on 22 to 24 October and ended on 20 to 22 November. Three distinct start dates cover the whole span.
This is why a calendar printed with a single fixed range for the month is right in most years and wrong in the rest. The table below sets out the documented years grouped by the Gregorian date the month began on, so the exact correspondence can be read off directly rather than estimated.
When Aban began
The month lengths are set by the calendar's own rule, but the year starts at the spring equinox — so the Gregorian day this month begins on is not the same every year.
Across the 101 years below, Aban began on 3 different Gregorian dates. A calendar printed with one fixed range is right for most of them and wrong for the rest.
From 1950-10-23 to 2050-11-21.
October 22
1996, 2000, 2004, 2008, 2012, 2016, 2020, 2024, 2028, 2029, 2032, 2033, 2036, 2037, 2040, 2041, 2044, 2045, 2048, 2049
October 23
1950, 1952, 1953, 1954, 1956, 1957, 1958, 1960, 1961, 1962, 1963, 1964, 1965, 1966, 1967, 1968, 1969, 1970, 1971, 1972, 1973, 1974, 1975, 1976, 1977, 1978, 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1997, 1998, 1999, 2001, 2002, 2003, 2005, 2006, 2007, 2009, 2010, 2011, 2013, 2014, 2015, 2017, 2018, 2019, 2021, 2022, 2023, 2025, 2026, 2027, 2030, 2031, 2034, 2035, 2038, 2039, 2042, 2043, 2046, 2047, 2050
October 24
1951, 1955, 1959
Sources
- Borkowski, The Persian Calendar for 3000 Years — the vernal-equinox anchoring that fixes every month boundary
- The Solar Hijri calendar's own month lengths: thirty-one days in the first six months, thirty in the next five, and twenty-nine or thirty in the last
- The traditional borj names, used as the month names of the Solar Hijri calendar in Afghanistan, where a month is also referred to by its number