This article needs additional citations for verification .(February 2017) |
The Pax calendar was invented by James A. Colligan, SJ in 1930, as a perennializing reform of the annualized Gregorian calendar. [1]
No. | Name | Days |
---|---|---|
01 | January | 28 |
02 | February | 28 |
03 | March | 28 |
04 | April | 28 |
05 | May | 28 |
06 | June | 28 |
07 | July | 28 |
08 | August | 28 |
09 | September | 28 |
10 | October | 28 |
11 | November | 28 |
12 | Columbus | 28 |
13 | Pax (leap week) | 7 |
13/14 | December | 28 |
The common year is divided into 13 months of 28 days each, whose names are the same as in the Gregorian calendar, except that a month called Columbus occurs between November and December. The first day of every week, month and year would be Sunday.
Unlike other perennial calendar reform proposals, such as the International Fixed Calendar and the World Calendar, it preserves the 7-day week by periodically intercalating an extra seven days to a common year of 52 weeks (364 days). In leap years, a one-week month called Pax would be inserted after Columbus.
To get the same mean year as the Gregorian Calendar this leap week is added to 71 of the 400 years in the cycle. The years with leap week are years whose last two digits are a number that is divisible by six (including 00) or 99: however, if a year number ending in 00 is divisible by 400, then Pax is cancelled.
Duncan Steel mentions the Pax Calendar proposal: [2]
As a matter of fact, this leap-week idea is not a new one. and such calendars have been suggested from time to time. ... In 1930, there was another leap-week calendar proposal put forward, this time by a Jesuit, James A. Colligan, but once more the Easter question scuppered it within the Catholic Church.
Unlike the International Fixed Calendar, the Pax calendar has a new year day that differs from the Gregorian New Year's Day. This is a necessary consequence of it intercalating a week rather than a day.
The following tables compare the Gregorian dates (left column) of New Year's Day in the Pax Calendar for various years. Dates in December occur in the preceding Gregorian year. Dates in bold are Sundays. The Pax years run sequentially down each column (from second-left to right), and a new column is begun when the year would need to go further up the column. Places marked "leap" means that there was no Pax year in the sequence which corresponded to that Gregorian date.
Jan 04 1931 Jan 03 1932 1937 1943 Jan 02 leap 1938 1944 1949 1955 Jan 01 1928 1933 1939 leap 1950 1956 1961 1967 Dec 31 leap 1934 1940 1945 1951 leap 1962 1968 1973 1979 Dec 30 1929 1935 leap 1946 1952 1957 1963 leap 1974 1980 1985 Dec 29 1930 1936 1941 1947 leap 1958 1964 1969 1975 leap 1986 Dec 28 leap 1942 1948 1953 1959 leap 1970 1976 1981 1987 Dec 27 leap 1954 1960 1965 1971 leap 1982 1988 Dec 26 leap 1966 1972 1977 1983 leap Dec 25 leap 1978 1984 1989 Dec 24 leap 1990
Jan 02 2000 Jan 01 leap Dec 31 2001 2007 Dec 30 1991 2002 2008 2013 2019 Dec 29 1992 1997 2003 leap 2014 2020 2025 2031 Dec 28 leap 1998 2004 2009 2015 leap 2026 2032 2037 2043 Dec 27 1993 1999 leap 2010 2016 2021 2027 leap 2038 2044 2049 Dec 26 1994 2005 2011 leap 2022 2028 2033 2039 leap 2050 Dec 25 1995 2006 2012 2017 2023 leap 2034 2040 2045 2051 Dec 24 1996 leap 2018 2024 2029 2035 leap 2046 2052 Dec 23 leap leap 2030 2036 2041 2047 leap Dec 22 leap 2042 2048 2053 Dec 21 leap 2054
The next table shows what happens around a typical turn of the century and also the full range (18 Dec to 6 Jan) of 19 days that the Pax Calendar New Year Day varies against the Gregorian calendar.
Jan 06 2301 2307 Jan 05 2302 2308 Jan 04 2303 leap Jan 03 2304 2309 Jan 02 2101 2107 leap 2310 Jan 01 2102 2108 2305 2311 Dec 31 2103 leap 2300 2306 2312 Dec 30 2104 2109 leap Dec 29 leap 2110 Dec 28 2105 2111 2291 Dec 27 2100 2106 2112 2292 2297 Dec 26 leap leap 2298 Dec 25 2293 2299 Dec 24 2091 leap 2294 Dec 23 2092 2097 2295 Dec 22 leap 2098 2296 Dec 21 2093 2099 leap Dec 20 2094 Dec 19 2095 Dec 18 2096
Colligan published multiple alternative methods of organising the months, including three 12-month plans in addition to the 13-month plan, and in a follow-up work focused on two possible 12-month calendars, in which Pax would be between September and October. He also provided two alternatives to the leap week plan, either extending one or two Mondays per year to 48 hours or making Pax a month of 28 or 21 days to be added 18 times in 400 years. [3]
Intercalation or embolism in timekeeping is the insertion of a leap day, week, or month into some calendar years to make the calendar follow the seasons or moon phases. Lunisolar calendars may require intercalations of both days and months.
The Julian calendar is a solar calendar of 365 days in every year with an additional leap day every fourth year. The Julian calendar is still used in parts of the Eastern Orthodox Church and in parts of Oriental Orthodoxy as well as by the Berbers, whereas the Gregorian calendar is used in most parts of the world.
A leap year is a calendar year that contains an additional day added to keep the calendar year synchronized with the astronomical year or seasonal year. Because astronomical events and seasons do not repeat in a whole number of days, calendars that have a constant number of days in each year will unavoidably drift over time with respect to the event that the year is supposed to track, such as seasons. By inserting ("intercalating") an additional day or month into some years, the drift between a civilization's dating system and the physical properties of the Solar System can be corrected. A year that is not a leap year is a common year.
The International Fixed Calendar is a proposed calendar reform designed by Moses B. Cotsworth, first presented in 1902. The solar calendar divides the year into 13 months of 28 days each. A type of perennial calendar, every date is fixed to the same weekday every year. Though it was never officially adopted at the country level, the entrepreneur George Eastman instituted its use at the Eastman Kodak Company in 1928, where it was used until 1989. While it is sometimes described as the 13-month calendar or the equal-month calendar, various alternative calendar designs share these features.
The Roman calendar was the calendar used by the Roman Kingdom and Roman Republic. Although the term is primarily used for Rome's pre-Julian calendars, it is often used inclusively of the Julian calendar established by the reforms of the dictator Julius Caesar and emperor Augustus in the late 1st century BC.
The World Calendar is a proposed reform of the Gregorian calendar created by Elisabeth Achelis of Brooklyn, New York in 1930.
The Darian calendar is a proposed system of timekeeping designed to serve the needs of any possible future human settlers on the planet Mars. It was created by aerospace engineer, political scientist, and space jurist Thomas Gangale in 1985 and named by him after his son Darius. It was first published in June 1986. In 1998 at the founding convention of the Mars Society the calendar was presented as one of two calendar options to be considered along with eighteen other factors to consider for the colonization of Mars.
Dominical letters or Sunday letters are a method used to determine the day of the week for particular dates. When using this method, each year is assigned a letter depending on which day of the week the year starts.
Calendar reform or calendrical reform is any significant revision of a calendar system. The term sometimes is used instead for a proposal to switch to a different calendar design.
The determination of the day of the week for any date may be performed with a variety of algorithms. In addition, perpetual calendars require no calculation by the user, and are essentially lookup tables. A typical application is to calculate the day of the week on which someone was born or a specific event occurred.
A leap week calendar is a calendar system with a whole number of weeks in a year, and with every year starting on the same weekday. Most leap week calendars are proposed reforms to the civil calendar, in order to achieve a perennial calendar. Some, however, such as the ISO week date calendar, are simply conveniences for specific purposes.
A perpetual calendar is a calendar valid for many years, usually designed to look up the day of the week for a given date in the past or future.
The Ethiopian calendar, or Ge'ez calendar, is the official calendar in Ethiopia. It is used as both the civil calendar and an ecclesiastical calendar. It is the liturgical year for Ethiopian and Eritrean Christians belonging to the Orthodox Tewahedo Churches, Eastern Catholic Churches, and Eastern Protestant Christian P'ent'ay Churches. Most Protestants in the diaspora have the option of choosing the Ethiopian calendar or the Gregorian calendar for religious holidays, with this option being used given that the corresponding eastern celebration is not a public holiday in the western world. The Ethiopian calendar is a solar calendar that has more in common with the Coptic calendar of the Coptic Orthodox Church of Alexandria and Coptic Catholic Church, but like the Julian calendar, it adds a leap day every four years without exception, and begins the year on 29 August or 30 August in the Julian calendar. A gap of seven to eight years between the Ethiopian and Gregorian calendars results from an alternative calculation in determining the date of the Annunciation.
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.
The solar cycle is a 28-year cycle of the Julian calendar, and 400-year cycle of the Gregorian calendar with respect to the week. It occurs because leap years occur every 4 years, typically observed by adding a day to the month of February, making it February 29th. There are 7 possible days to start a leap year, making a 28-year sequence.
An annual calendar is a representation of the year that expires with the year represented, or that must be altered annually to remain current. The term takes different but related meanings across two contexts. One is for static (synchronic) calendars, such as wall calendars or calendar systems. The other is for dynamic (diachronic) calendars, such as digital calendars or timepieces. Static representations of the Gregorian calendar year are annual, because the weekdays of Gregorian dates vary from year to year. The calendar representing one year will not serve for the next year. With perennial calendars, the same representation of the year serves for every year. Perpetual calendars, in this context, are computation devices for determining the weekdays of dates in any given year, or for representing a wide range of annual calendars.
A century leap year is a year in the Gregorian calendar that is evenly divisible by 400 and is thus a leap year.
The Gregorian calendar is the calendar used in most parts of the world. It was introduced on February 24 with a papal bull, and went into effect in October 1582 by Pope Gregory XIII as a modification of, and replacement for, the Julian calendar. The principal change was to space leap years differently so as to make the average calendar year 365.2425 days long, more closely approximating the 365.2422-day 'tropical' or 'solar' year that is determined by the Earth's revolution around the Sun.
The Hanke–Henry Permanent Calendar (HHPC) is a proposal for calendar reform. It is one of many examples of leap week calendars, calendars that maintain synchronization with the solar year by intercalating entire weeks rather than single days. It is a modification of a previous proposal, Common-Civil-Calendar-and-Time (CCC&T). With the Hanke–Henry Permanent Calendar, every calendar date always falls on the same day of the week. A major feature of the calendar system is the abolition of time zones.
A perennial calendar is a calendar that applies to any year, keeping the same dates, weekdays and other features.