GREGORIAN CALENDAR CALENDAR JULIAN The Gregorian calendar is the calendar
currently used in most parts of the world. Designed by a panel of scientists under the direction of Christophorus Clavius
to correct secular drift
Julian calendar, its name bears the name of its instigator
Gregory XIII, Pope
of
1572 to 1585
. Its point of departure, the year
1, is estimated as the year of the birth of Jesus
.
Summary [
hide] 1 Structure
Calendar 1.1 Subdivisions 1.2 The adjustment Gregorian 2 Introduction of the Gregorian calendar 3 Debates on the Gregorian calendar in history 4 Use by historians 5 Trivia 6 See also 6.1 Bibliography 6.2 Internal links 6.3 External links
/ /
Structure Timetable:
The structure of the Gregorian calendar is similar to the Julian calendar
of ancient Rome
in force until then. It is a solar calendar, based on the revolution of Earth around the Sun in 365.2422 days
than 24 hours
of 60 to 60 minutes second metric. The Gregorian calendar gives an average time of the year of 365.2425 days, to ensure a whole number of days per year are added every four years a leap day on February 29
(see
leap year) with the exception of leap years centuries that are removed, unless the year is divisible by 400. He is currently an error of about one day 3000 years.
The Gregorian calendar uses the rules of the Gregorian
.
Subdivisions
The Gregorian calendar is divided into twelve months
grouped into four quarters
:
Q1 Q2 Q3
Q4
January, 31 days in February
, 28 or 29 days
March , 31 days.
April, May
30 days, 31 days
June, 30 days.
July, 31 days
August, 31 days
September, 30 days.
October, 31 days
November, December
30 days, 31 days.
90 or 91 days
91 days 92 days 92 days
A period of seven days forms a week
. The days of a week have a name: in French,
Monday, Tuesday
,
Wednesday,
Thursday, Friday
,
Saturday and Sunday
. A period of four weeks as a
months and a period of twelve months form a year
.
era commonly used with the Gregorian calendar is the
Christian era, that is to say, "AD" (Anno Domini
in Latin phrase still used in English and most often noted after year abbreviated AD, and formerly designated as the French year of grace or year of the Lord).
year "zero" of it would exist?
A calendar is a measure of time, a count of years, months and days. One measure assesses the magnitude of the observed object. She can not leave until zero. But none, except that The starting point is the landmark. Here, in the sense of time, so this is a moment, not a period of time. (Zero is zero). Came after a year, said it was the first year. Let the analogy with distance, one-dimensional notion of space: a runner from a given point, and after one kilometer, it is called the km 1. Presumably also, eg, measurement of distances in kilometers on road maps. The first year of any schedule can therefore only one year (as on 1 km traveled is km 1).
also about those who claim that the calendars would have to include the years zero: some, noting that the makers of the time schedules were not retained from year zero, believed that the Romans (without thinking about the Semites and other Christians) did not know the existence of zero. But in fact, having realized that the calendars should not logically include the year zero, our ancestors have not been and we can not conclude that they did not know zero. The era
above is the pre-Christian era and is counted in the opposite direction, again from time zero. It is in the direction "before Christ", often abbreviated in French "av. AD. The years "x ave. J.-C. also noted "-x".
adjustment Gregorian
The introduction of the Gregorian calendar replace the Julian calendar began on 15 October 1582 with countries claiming alignment Rome
Spain ,
Portugal, United States of the Italian peninsula (including
Papal States). The aim was to fight against the drift of the date of Easter
(Sunday after the first moon of the equinox fictitious spring) that moved to summer.
In fact the major reform and sufficient eliminating this drift (which was easily applied in other countries by the limited reform of the Julian calendar) was the mode of application of leap years in century years. The main difference between the Gregorian calendar and its predecessor, the Julian calendar
unreformed, lies in the distribution of leap years.
As noted above, the tropical year
average, that is to say the period of revolution of the Earth around the Sun, hard 365.24219 days. By inserting a leap day every four years, attributed to the Julian calendar year an average of 365.25 days. This induces a lag of about 8 days per thousand compared to real time, with the effect that the date of Easter
determined by the March 21
(sort of
spring equinox legal), slipped gradually away from the actual spring equinox, which this last "bump" in the calendar slowly, reaching around 10 March (Julian) at
sixteenth century. It is therefore considered as
common years (Years of 365 days) vintages that are multiples of 100 without being multiples of 400. Thus 1600 and 2000 were leap years but not 1700, 1800, 1900, which were common. Similarly, 2100, 2200, 2300 will be common, while 2400 will be a leap year
.
Applying this rule, we arrive at a year of 365.2425 days instead of 365.24219 days is an excess of three days in 10,000 years. It was proposed to amend the rule to consider the multiple years of 4000 to be normal. But because of the shortening of the tropical year estimated at 0.5 sec per century and elongation of the day of 1.64 milliseconds per century, it is unrealistic to achieve this level of accuracy, uncertainty over the duration of the year to 10 000 years of the same order of magnitude.
The introduction of the Gregorian calendar also includes a second reform implementation more difficult, offset Gregorian suppressed ten calendar days, between 4
October 1582 and
15 October 1582 for countries that immediately followed Rome, which allowed for reattaching the spring equinox on March 21, as was the case at the beginning of the Christian era, the First Council of Nicaea
in
325.
These ten days allowed to catch a shot taken by the growing delay the Julian calendar the dates of the equinoxes since the beginning of the Christian era, that is to say more than 12 centuries before, and find the correlation between the spring equinox on March 21 and calendar. 9 years leap were counted too much (500, 600, 700, 900, 1000, 1100, 1300, 1400 and 1500 under the new calculation rules) if the Julian calendar did not induce this shift for the entire period until 'in 1582, but the corrections had been applied earlier during this period by failing to add a day in late February in some years that should have been leap (following the old rule of the Julian calendar).
However, some countries have been slow to implement the adjustment of the Gregorian century years (
adjustment dates by country ), and therefore counted as the leap year 1700 (according to the unreformed Julian calendar) This has increased the lag time in eleven days. Sweden, which used the Julian calendar was first attempted to apply only the Gregorian adjustment rule in 1700 (non-leap) without applying the offset of 10 days and then rebounded in 1704 by adding two days in the month of February (leap year doubling) to return to the old Julian calendar still used in England and in Protestant and Orthodox neighbors. The
Sweden and England
fully implements the Gregorian calendar until later, under the influence of
Germany, the Netherlands
and
Switzerland which states used simultaneously Julian and Gregorian calendars after they were Protestant or Catholic, and when they Unification wanted to standardize schedules.
The third reform of the Gregorian calendar was numbered years beginning in January and not March as in the Julian calendar (the beginning of the year in the Julian calendar to itself varied - see the article
and external links). This reform helps to match the pagan holidays of New Year in time for Christmas, not just before the holy time of Easter. In many countries, this reform has been implemented for years or even several centuries after the adjustment and offset Gregorian. However this will not be the case of Orthodox countries, including the year began in September.
Introduction of the Gregorian calendar
Moved from the beginning of the reign of Gregory, and supported by England in a
Ecumenical Council, the calendar takes its name when the Pope decides to adopt it too. First, in many countries refused on religious grounds or political (conflict between the Papacy
and some countries
Protestants, and limited application by the Orthodox churches which accept the new way of calculating years in the secular calendar but without applying the Julian calendar shift) the Gregorian calendar was released slowly
in October 1582 in Italy
at
Portugal, in its Brazilian colony, and Spain
,
in late 1582 in France
in
Austria in Poland
,
in the years 1582 to 1584
in the English colonies in Latin America
and until
California, and the Philippines
,
the sixteenth century the eighteenth century
in the French colony of Canada
, in
the years 1583 to 1590 in continental Europe and Central Lutheran Non
,
in 1600 in Scotland, in
1610 in northern Poland
,
in
1648 (date the Treaty of Westphalia
) in Alsace
,
in 1700 in Iceland and Greenland
,
in 1752 to United Kingdom and its colonies on the east coast of North America, and is now north-western United States
,
in 1753 in Sweden,
in the late eighteenth century
in Australia ,
the nineteenth century in Korea,
in 1872 in Albania,
in 1873 to Japan,
in 1912
Taiwan to
,
in 1915 in Lithuania and Estonia
,
in 1916 in Bulgaria,
in 1918
in most countries of the Tsarist empire
Orthodox :
Russia ,
Belarus, Moldova
,
Ukraine, Georgia
,
Estonia, Armenia
in
Azerbaijan, and in the countries of Central Asia
:
Turkmenistan, Uzbekistan
,
Tajikistan, Kyrgyzstan
,
Kazakhstan,
in 1919 for Catholic
Romania,
in 1920
for Orthodox Romania,
in 1924 in Greece,
in 1927 in Turkey,
the twentieth century in Africa West, Central, and South America.
countries that use the Gregorian calendar associated with another calendar are:
the countries of North Africa
: the
Algeria, Morocco
the the
Tunisia, Mauritania
the the
Libya, the
Egypt,
the Sudan, the Eritrean
,
the Middle East: Israel
the
Jordan, Syria
the , the
Iraq, the
Kuwait, Oman
the
Yemen the
Qatar,
large Asian countries: the
China, Taiwan
, the
India And the Burma
the
Thailand, Cambodia
the the
Mongolia, Nepal
the .
Only the
Saudi Arabia, the Iran
, the
Afghanistan, the Pakistan
, the
Ethiopia and Vietnam
do not use the Gregorian calendar.
Debates on the Gregorian calendar in History:
If the principle of the Gregorian adjustment has not been questioned, it is not true of its internal structure. Critics
wore in France
its relationship with the
Christianity , through the Christian era
, religious festivals, and references to saints
in
diaries. The diaries were in effect at the time a major media in the French countryside.
This motivated some projects such as calendars lay the
the Republican calendar French Revolution
. Unlike
metric, it does not succeed: it is true that the principle not to rest one day out of ten (decades) instead of seven could not enthuse. Another reason, more technical, was that the shift schedule between France and neighboring countries posed some difficulties in the border areas.
Another draft timetable
secular (the
fixed schedule) has been proposed by Auguste Comte
: calendar
positivist. This has hardly been used outside of the Count and a few disciples.
Other critics seem to concern the very construction of the calendar month
variable length (28 to 31 days) which makes such an analysis of economic statistics;
difficult correspondence between the names of days and number in the month, duration
quarters (the second quarter being for example shorter than the third);
weeks (4.33) per month;
change the date of some holidays like Easter
.
But originality is not related to human choices, timing is simply trying to follow the astronomical year. It does not involve a whole day and summer and winter periods are 7 days apart in time. The lunar cycle is not fixed either. Nevertheless it must be a number of whole days in a year to navigate and monitor the length of day (sunrise
Sun ).
This difficulty has led many reform proposals to use the principle of
epagomena days. It is a white day that does not count the week. By adding one (or two leap years) day epagomenal year, we come to gain equality 365 = 7 × 52 + 1. The same idea with
additional days in the Republican calendar
of the French Revolution.
months duration was chosen to correspond approximately to a lunar cycle. Thus, even a non-literate population could know about, observing the change in appearance of the moon, when a month had elapsed, the reference to the moon was important for the sailors (to know the tides
) and farmers (night work fields) of a predominantly rural population.
If today this relationship is not evident in our urban civilization
, the vast majority of reforms trying to keep a calendar month about a lunar month.
Note, however, the emergence of the Badi `calendar
used in the Baha'i
. If it is also based on a solar year, the latter starting at the vernal equinox on March 21
, its originality lies in the abandonment of reference for the duration of the lunar month. A year of this calendar has 19 months because of 19 days (361 days). 4 to 5 additional days needed to complete one year are inserted between the 18th and 19th months and the intercalary days are appointed.
Over the last three centuries, other reform proposals have been advanced. The best known were the proposals for universal calendar
and
fixed schedule. The mid-twentieth century
, the League of Nations
then the United Nations
led studies to reform the calendar. These were abandoned under pressure from countries like the United States
the
UK, the Netherlands
or
Indonesia, officially so as not to disrupt religious traditions.
Many authors of science fiction
played with the idea that the timing landowner might one day be used in any known space, while almost everyone has forgotten its original purpose or even the existence of Earth itself.
On a more down to earth at the approach of the year
2000, when it came to adapt computer systems
which for the most part, were affected by the bug
Year 2000 through the system date and algorithms
of
dating used in computer programs
, the question arose between the authorities of different religions
to know what was the baseline schedule. Following a debate in the United States, it was finally decided to retain, for the sake of simplicity, the Gregorian calendar ...
use by historians: 1582
Before, we used the Julian calendar
. So this calendar is also used by historians
for that period, as they work with dates on the documents. The Gregorian calendar is rarely used
retroactively.
Trivia:
in Edmond Rostand's Cyrano de Bergerac
says the
26 September 1655 was a Saturday. It was actually a Sunday!
Teresa of Avila died in the night shift from October 4 to October
15 1582. The date of the feast of Saints being established after their death (their "birthday into heaven"), the feast of this holy tomb October 15.
Shakespeare and Cervantes
died on the same date but not the same day, the United Kingdom - for its part
Anglican - did not immediately adopted the Gregorian calendar.
Montaigne in his Essays
mentions the difficulties his contemporaries tried to move gradually to the new calendar.
Remains Calendar Julian remain fossilized in the strata of popular culture
. They are removed regularly mark the publication of various calendars, almanacs and other publications agricultural gardening. Examples:
"At Sainte Luce, the days get longer the jump of a flea, AT Nadal (Christmas) from the foot of a gal (cock) And the new year's not an ox." These dates are those of the Julian calendar. In our current schedule we celebrate the Holy Luce December 13 but the days begin to lengthen until 22 December.
"The Saint Barnabas (June 11) is the longest day of the year." This saying reflects today the 10-day lag introduced during the adoption of the Gregorian calendar to catch the Julian calendar on the Sun.
"In St. Matthew (September 21), day equals the night." he chants the advent of the autumn equinox in accordance with the existing timetable.
"At St. Catherine's (November 25th), everything takes root!" Excellent reference for gardeners to make most plantation
Denarius (currency) 
