Gregorian calendar
Also known as: Western calendar · Christian calendar · New Style · new Western calendar · new Christian calendar
- 1Implemented in October 1582.
- 2Established by the papal bull Inter gravissimas.
- 3Introduced by Pope Gregory XIII.
- 4Replaced the Julian calendar.
- 5Average year length of 365.2425 days.
- 6Approximates the 365.2422-day tropical year.
The Gregorian calendar is the calendar used in most parts of the world.
Connections1
Scientific contribution by the university's scholars
The University of Salamanca was commissioned by the Vatican to provide the astronomical calculations necessary for the reform of the calendar in 1582.
The Gregorian calendar is the internationally recognized civil calendar used across most of the world today. It was introduced in October 1582 through the papal bull Inter gravissimas, issued by Pope Gregory XIII, to replace the older Julian calendar.
Wikimedia Commons gallery media for Gregorian calendar.Wikimedia Commons; William Hogarth; The Yorck Project (2002) 10.000 Meisterwerke der Malerei (DVD-ROM), distributed by DIRECTMEDIA Publishing GmbH. ISBN : 3936122202 .; Public domain; Wikimedia Commons: Gregorian calendarGregory XIII, Pope (1502 - 1585)Wikimedia Commons; Esaias van Hulsen; Engraving, 30.5 x 18.6 cm / Sheet: 32.1 x 20.6 cm. Retrieved from the Smithsonian Institution Libraries, Gregory XIII, Pope (1502 - 1585); Public domain; Wikimedia Commons: Gregorian calendarKalender ab 15.Oktober 1582Wikimedia Commons; Karl Nimtsch; Own work; CC BY-SA 3.0; Wikimedia Commons; Wikidata P18 (image) The primary innovation of this system was a refined calculation of leap years. By adjusting the frequency of these years, the average calendar year was set to 365.2425 days. This modification allowed the calendar to align more precisely with the 365.2422-day tropical year, which is defined by the Earth's revolution around the Sun.