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Leap Year |

A leap year is a year in i beg your pardon an extra work is included to the calendar in order come synchronize it v theseasons. Due to the fact that the tropic year is 365.242190 days long, a leap year need to be included roughlyonce every 4 years (four times the fractional day provides ). In a leap year, the extra work (known as a leap day) is added at the finish of February, offering it 29 rather of the usual 28 days. In the Gregorian calendar currently in use worldwide (except probably the Russian andIranian calendars), there is a leap year every year divisible by four except for yearswhich are both divisible through 100 and not divisible through 400. Therefore, the year 2000 will certainly be a leap year, however theyears 1700, 1800, and also 1900 to be not. The complete list that leap years in the an initial half that the 21st century is therefore2000, 2004, 2008, 2012, 2016, 2020, 2024, 2028, 2032, 2036, 2040, 2044, and 2048.The extra dominance involving century is an additional correction to comprise for the reality that one extra work every fouryears is slightly too lot correction (). This scheme results in the vernal equinox gradually shifting that is date between March 19 and also 21, gift shifted once every leap year, and then gift abruptly shifted innon-leap centuries (see number above).In the Gregorian calendar, 97 years out of every 400 space leap years, providing the total variety of days in 400 yearsas You are watching: Leap years of the 21st century The leap year was presented in the Julian calendar in 46 BC. However, about 10 BC, the was discovered thatthe clergymans in fee of computing the calendar had actually been including leap year every three years instead of the 4 decreedby Caesar (Vardi 1991, p.239). As a result of this error, no more leap years were included until 8 AD. Leap yearswere as such 45 BC, 42 BC, 39 BC, 36 BC, 33 BC, 30 BC, 27 BC, 24 BC, 21 BC, 18 BC, 15 BC, 12 BC, 9 BC, 8 AD, 12 AD,and every 4th year afterwards (Tøndering), until the Gregorian calendar was presented (resulting inskipping 3 out that every 4 centuries). The UNIX command cal erroneously lists 4AD together a leap year (Vardi 1991).Century, Gregorian Calendar, Julian Calendar, Leap Day, Leap Second, Millennium, Year Hollon, B. "An development to Calendars." http://www.12x30.net/intro.html. Seidelmann, P.K. Explanatory supplement to the astronomical Almanac. Mill Valley, CA: University science Books, 1992.Starr, A. "Leap Day/Leap Year." http://www.emailman.com/leapday/. Strohsacker, J. " See more: How To Catch Suicune Leaf Green ? Firered/Leafgreen February 29 Leap Day." http://www.mystro.com/leap.htm. Tøndering, C. "Frequently inquiry Questions about Calendars." http://www.tondering.dk/claus/calendar.html. Vardi, I. "The Julian Calendar." §3.5.1 in Computational Recreations in Mathematica. Redwood City, CA: Addison-Wesley, p.44, 1991. |