The Gregorian calendar is internationally the most widely used civil calendar. It is named after Pope Gregory XIII, who introduced it in October 1582.
The calendar was a refinement to the Julian calendar involving a 0.002% correction in the length of the year. The motivation for the reform was to stop the drift of the calendar with respect to the equinoxes and solstices—particularly the vernal equinox, which set the date for Easter celebrations. Transition to the Gregorian calendar would restore the holiday to the time of the year in which it was celebrated when introduced by the early Church. The reform was adopted initially by the Catholic countries of Europe. Protestants and Eastern Orthodox countries continued to use the traditional Julian calendar and adopted the Gregorian reform after a time, for the sake of convenience in international trade. The last European country to adopt the reform was Greece, in 1923.
The Gregorian reform contained two parts: a reform of the Julian calendar as used prior to Pope Gregory XIII’s time and a reform of the lunar cycle used by the Church, with the Julian calendar, to calculate the date of Easter. The reform was a modification of a proposal made by Aloysius Lilius. His proposal included reducing the number of leap years in four centuries from 100 to 97, by making 3 out of 4 centurial years common instead of leap years. Lilius also produced an original and practical scheme for adjusting the epacts of the moon when calculating the annual date of Easter, solving a long-standing obstacle to calendar reform.
The Gregorian reform modified the Julian calendar’s scheme of leap years as follows:
Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400. For example, the years 1700, 1800, and 1900 are not leap years, but the years 1600 and 2000 are.
In addition to the change in the mean length of the calendar year from 365.25 days (365 days 6 hours) to 365.2425 days (365 days 5 hours 49 minutes 12 seconds), a reduction of 10 minutes 48 seconds per year, the Gregorian calendar reform also dealt with the accumulated difference between these lengths. The canonical Easter tables were devised at the end of the third century, when the vernal equinox fell either on 20 March or 21 March depending on the year’s position in the leap year cycle. As the rule was that the full moon preceding Easter was not to precede the equinox, the date was fixed at 21 March for computational purposes and the earliest date for Easter was fixed at 22 March. The Gregorian calendar reproduced these conditions by removing ten days.
To unambiguously specify the date, dual dating or Old Style (O.S.) and New Style (N.S.) are sometimes used with dates. Dual dating uses two consecutive years because of differences in the starting date of the year, or includes both the Julian and Gregorian dates. Old Style and New Style (N.S.) indicate either whether the start of the Julian year has been adjusted to start on 1 January (N.S.) even though documents written at the time use a different start of year (O.S.), or whether a date conforms to the Julian calendar (O.S.) rather than the Gregorian (N.S.).
The Gregorian calendar continued to use the previous calendar era (year-numbering system), which counts years from the traditional date of the nativity (Anno Domini), originally calculated in the 6th century by Dionysius Exiguus. This year-numbering system, also known as Dionysian era or Common Era, is the predominant international standard today.
Born: Apr 27, 1923 · Cleveland, OH
Died: Dec 23, 2012 · New Haven, CT
Education: Smith CollegeHighlights
- 1966: Harris met Tarnower, a cardiologist (later known, due to a popular diet book he published, as the “Scarsdale Diet Doctor”), in December 1966, the year after her divorce.
- 1980: On March 10, 1980, Harris drove 264 miles from the Madeira School in Virginia to Tarnower’s home in Purchase, New York, with a .32 caliber revolver in her possession.
- 1981: Harris’ murder trial was depicted in the 1981 made-for-television movie The People vs. Jean Harris.
- 1992: Eleven years after Harris’s conviction, Governor Mario Cuomo commuted the remainder of her sentence on December 29, 1992, as she was being prepped for quadruple bypass heart surgery.
- 1997: In the 1997 Seinfeld episode “The Summer of George,” Raquel Welch plays herself portraying Harris in a fictional Tony Award-winning musical about the murders called Scarsdale Surprise.
- 2012: Harris died of natural causes on December 23, 2012, at an assisted-living center in New Haven, Connecticut at age 89.
Born: Jan 26, 1961 (age 56) · Brantford, Canada
Height: 6′ 0″ (1.83 m)
Net worth: $200 million USD (2016)
Spouse: Janet Jones (m. 1988)
Children: Paulina Gretzky (Daughter) · Emma Gretzky (Daughter) · Tristan Gretzky (Son) · Trevor Gretzky (Son) · Ty Gretzky (Son)
Siblings: Keith Gretzky (Brother) · Brent Gretzky (Brother) · Glen Gretzky (Brother) · Kim Gretzky (Sister)
- 1979: One of the highlights of Gretzky’s season was his appearance in the 1979 WHA All-Star Game.
- 1985: The Oilers also won the Cup with Gretzky in 1985, 1987 and 1988.
- 1988: Wayne Gretzky married Janet Jones on July 16, 1988.
- 1988: His trade to the Los Angeles Kings on August 9, 1988, had an immediate impact on the team’s performance, eventually leading them to the 1993 Stanley Cup Finals, and he is credited with popularizing hockey in California.
- 1996: On February 27, 1996, Gretzky joined the St. Louis Blues in a trade for Patrice Tardif, Roman Vopat, Craig Johnson, and two draft picks (Peter Hogan and Matt Zultek).
- 1998: The next season, Gretzky broke Gordie Howe’s career goal-scoring record and won the scoring title, but the team began a long slide, and despite numerous player and coaching moves, they failed to qualify for the playoffs again until 1998.
Start date: Aug 02, 1990
End date: Feb 28, 1991