46 relations: Ancient Egypt, Augustus, Ayyám-i-Há, Bahá'í calendar, Bengali calendars, Blue moon, Buddhist calendar, Calendar year, Celtic calendar, Chinese calendar, Common year, Computus, Coptic calendar, Decree of Canopus, Egyptian calendar, Ethiopian calendar, French Republican Calendar, Gregorian calendar, Haab', Hebrew calendar, Hegira, Hindu calendar, Igbo calendar, Indian national calendar, Intercalated Games, International Earth Rotation and Reference Systems Service, Iranian calendars, Islamic calendar, ISO 8601, ISO week date, Julian calendar, Leap second, Leap year, Lunar month, Lunisolar calendar, March equinox, Metonic cycle, Month, Nasi', New moon, Ptolemy III Euergetes, Solar Hijri calendar, Tabular Islamic calendar, Thai lunar calendar, Tropical year, World Calendar.
Ancient Egypt was a civilization of ancient Northeastern Africa, concentrated along the lower reaches of the Nile River - geographically Lower Egypt and Upper Egypt, in the place that is now occupied by the countries of Egypt and Sudan.
Augustus (Augustus; 23 September 63 BC – 19 August 14 AD) was a Roman statesman and military leader who was the first Emperor of the Roman Empire, controlling Imperial Rome from 27 BC until his death in AD 14.
Ayyám-i-Há refers to a period of intercalary days in the Bahá'í calendar, when Bahá'ís celebrate the Festival of Ayyám-i-Há.
The Bahá'í calendar, also called the Badíʿ calendar (Badíʿ means wondrous or unique), is a solar calendar with years composed of 19 months of 19 days each (361 days) plus an extra period of "Intercalary Days".
The Bengali Calendar or Bangla Calendar (Baṅgābda) is a solar calendar used in the region of Bengal.
A blue moon is an additional full moon that appears in a subdivision of a year: either the third of four full moons in a season, or a second full moon in a month of the common calendar.
The Buddhist calendar is a set of lunisolar calendars primarily used in mainland Southeast Asian countries of Cambodia, Laos, Myanmar and Thailand as well as in Sri Lanka and Chinese populations of Malaysia and Singapore for religious or official occasions.
Generally speaking, a calendar year begins on the New Year's Day of the given calendar system and ends on the day before the following New Year's Day, and thus consists of a whole number of days.
The Celtic calendar is a compilation of pre-Christian Celtic systems of timekeeping, including the Gaulish Coligny calendar, used by Celtic countries to define the beginning and length of the day, the week, the month, the seasons, quarter days, and festivals.
The traditional Chinese calendar (official Chinese name: Rural Calendar, alternately Former Calendar, Traditional Calendar, or Lunar Calendar) is a lunisolar calendar which reckons years, months and days according to astronomical phenomena.
A common year is a calendar year with 365 days.
Computus (Latin for "computation") is a calculation that determines the calendar date of Easter.
The Coptic calendar, also called the Alexandrian calendar, is a liturgical calendar that was used by the Coptic Orthodox Church and is still used in Egypt.
The Decree of Canopus is a trilingual inscription in three scripts, which dates from the Ptolemaic period of Ancient Egypt.
The ancient Egyptian calendar was a solar calendar with a 365-day year.
The Ethiopian calendar (የኢትዮጵያ ዘመን አቆጣጠር; yä'Ityoṗṗya zämän aḳoṭaṭär) is the principal calendar used in Ethiopia and also serves as the liturgical year for Christians in Eritrea and Ethiopia belonging to the Eritrean Orthodox Tewahedo Church, Ethiopian Orthodox Tewahedo Church, Eastern Catholic Churches and Coptic Orthodox Church of Alexandria.
The French Republican Calendar (calendrier républicain français), also commonly called the French Revolutionary Calendar (calendrier révolutionnaire français), was a calendar created and implemented during the French Revolution, and used by the French government for about 12 years from late 1793 to 1805, and for 18 days by the Paris Commune in 1871.
The Gregorian calendar is the most widely used civil calendar in the world.
The Haab' is part of the Maya calendric system.
The Hebrew or Jewish calendar (Ha-Luah ha-Ivri) is a lunisolar calendar used today predominantly for Jewish religious observances.
The Hegira (also called Hijrah, هِجْرَة) is the migration or journey of the Islamic prophet Muhammad and his followers from Mecca to Yathrib, later renamed by him to Medina, in the year 622.
Hindu calendar is a collective term for the various lunisolar calendars traditionally used in India.
The Igbo calendar is the traditional calendar system of the Igbo people from present-day Nigeria.
The Indian national calendar, sometimes called the Shalivahana Shaka calendar, is used along with the Vikram Samvat calendar.
The Intercalated Olympic Games were to be a series of International Olympic Games halfway between what is now known as the Games of the Olympiad.
The International Earth Rotation and Reference Systems Service (IERS), formerly the International Earth Rotation Service, is the body responsible for maintaining global time and reference frame standards, notably through its Earth Orientation Parameter (EOP) and International Celestial Reference System (ICRS) groups.
The Iranian calendars (گاهشماری ایرانی Gâhshomâriye Irâni) are a succession of calendars invented or used for over two millennia in Iran (Persia).
The Islamic, Muslim, or Hijri calendar (التقويم الهجري at-taqwīm al-hijrī) is a lunar calendar consisting of 12 months in a year of 354 or 355 days.
ISO 8601 Data elements and interchange formats – Information interchange – Representation of dates and times is an international standard covering the exchange of date- and time-related data.
The ISO week date system is effectively a leap week calendar system that is part of the ISO 8601 date and time standard issued by the International Organization for Standardization (ISO) since 1988 (last revised in 2004) and, before that, it was defined in ISO (R) 2015 since 1971.
The Julian calendar, proposed by Julius Caesar in 46 BC (708 AUC), was a reform of the Roman calendar.
A leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time (UTC) in order to keep its time of day close to the mean solar time as realized by UT1.
A leap year (also known as an intercalary year or bissextile year) is a calendar year containing one additional day (or, in the case of lunisolar calendars, a month) added to keep the calendar year synchronized with the astronomical or seasonal year.
In lunar calendars, a lunar month is the time between two successive syzygies (new moons or full moons).
A lunisolar calendar is a calendar in many cultures whose date indicates both the moon phase and the time of the solar year.
The March equinox or Northward equinox is the equinox on the Earth when the subsolar point appears to leave the southern hemisphere and cross the celestial equator, heading northward as seen from Earth.
For astronomy and calendar studies, the Metonic cycle or Enneadecaeteris (from ἐννεακαιδεκαετηρίς, "nineteen years") is a period of very close to 19 years that is nearly a common multiple of the solar year and the synodic (lunar) month.
A month is a unit of time, used with calendars, which is approximately as long as a natural period related to the motion of the Moon; month and Moon are cognates.
Nasiʾ, Nasii, or Nasie (النسيء, al-Nasīʾ, "postponement") was an aspect of the calendar of pre-Islamic Arabia, mentioned in the Quran in the context of the "four forbidden months".
In astronomy, the new moon is the first lunar phase, when the Moon and Sun have the same ecliptic longitude.
Ptolemy III Euergetes (Πτολεμαῖος Εὐεργέτης, Ptolemaĩos Euergétēs "Ptolemy the Benefactor"; 284–222 BC) was the third king of the Ptolemaic dynasty in Egypt from 246 to 222 BCE.
The Solar Hijri calendar (gāh-shomāri-ye hejri-ye khorshidi; لمريز لېږدیز کلیز), also called the Solar Hejri calendar or Shamsi Hijri calendar, and abbreviated as SH, is the official calendar of Iran and Afghanistan.
The Tabular Islamic calendar (an example is the Fatimid or Misri calendar) is a rule-based variation of the Islamic calendar.
The Thai lunar calendar (ปฏิทินจันทรคติ,,, literally, Specific days according to lunar norms), or Tai calendar, is a lunisolar Buddhist calendar.
A tropical year (also known as a solar year) is the time that the Sun takes to return to the same position in the cycle of seasons, as seen from Earth; for example, the time from vernal equinox to vernal equinox, or from summer solstice to summer solstice.
The World Calendar is a proposed reform of the Gregorian calendar created by Elisabeth Achelis of Brooklyn, New York in 1930.
Calendrical intercalation, Embolism (timekeeping), Embolismic month, Epagomenal, Epagomenal day, Epagomenal days, Intercalary day, Intercalary days, Intercalary month, Intercalation (calendar), Intercaluary day, Leap month.