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Proleptic Calendar (other)
A proleptic calendar is a calendar that is applied to dates before its introduction. Examples include: * Proleptic Gregorian calendar The proleptic Gregorian calendar is produced by extending the Gregorian calendar backward to the dates preceding its official introduction in 1582. In nations that adopted the Gregorian calendar after its official and first introduction, dates occ ... * Proleptic Julian calendar * Symmetry454 {{disam Calendars ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proleptic Gregorian Calendar
The proleptic Gregorian calendar is produced by extending the Gregorian calendar backward to the dates preceding its official introduction in 1582. In nations that adopted the Gregorian calendar after its official and first introduction, dates occurring in the interim period of 15 October 1582 (the first date of use of Gregorian calendrical dates, being dated 5 October 1582 in the preceding Julian calendar) to the date on which the pertinent nation adopted the Gregorian calendar and abandoned the Julian calendar are sometimes 'Gregorianized' also. For example, the birthday of U.S. President George Washington was originally dated 11 February 1731 (Old Style) because Great Britain, of which he was born a subject, used (until September 1752) the Julian calendar and dated the beginning of English years as 25 March. After Great Britain switched to the Gregorian calendar, Washington's birthday was dated 22 February 1732 proleptically, according to the Gregorian calendar applied backward. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proleptic Julian Calendar
The proleptic Julian calendar is produced by extending the Julian calendar backwards to dates preceding AD 8 when the quadrennial leap year stabilized. The leap years that were actually observed between the implementation of the Julian calendar in 45 BC and AD 8 were erratic (see the Julian calendar article for details). A calendar obtained by extension earlier in time than its invention or implementation is called the " proleptic" version of the calendar. Likewise, the proleptic Gregorian calendar is occasionally used to specify dates before the introduction of the Gregorian calendar in 1582. Because the Julian calendar was used before that time, one must explicitly state that a given quoted date is based on the proleptic Gregorian calendar if that is the case. The Julian calendar itself was introduced by Julius Caesar, and as such is older than the introduction of the Anno Domini era (or the "Common Era"), counting years since the birth of Christ as calculated by Dionysus Ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symmetry454
The Symmetry454 calendar (Sym454) is a proposal for calendar reform created by Irv Bromberg of the University of Toronto, Canada. It is a perennial solar calendar that conserves the traditional month pattern and 7-day week, has symmetrical equal quarters in 82% of the years in its 293-year cycle, and starts every month on Monday. Calendar year The proposed calendar is laid out as follows: : The last 7 days of December, shown in grey, are intercalary days that are appended only to the end of leap years. The idea of months having 4 or 5 whole weeks is not new, having been proposed in the 1970s by Chris Carrier for the Bonavian Civil Calendar and by Joseph Shteinberg for his "Calendar Without Split Weeks". Whereas the former has 5 + 4 + 4 weeks per quarter, and the latter has 4 + 4 + 5 weeks per quarter, the Symmetry454 Calendar has a ''symmetrical'' 4 + 5 + 4 weeks per quarter, which is why it is named Symmetry454. Balanced quarters are desirable for businesses because they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |