Dionysius Exiguus invented Anno Domini years to date Easter.

Anno Domini ^[1] (Medieval Latin: In the year of (the/Our) Lord),^[2][3] abbreviated as AD or A.D., is a designation used to number years in the Julian and Gregorian calendars. More fully, years may be also specified as Anno Domini Nostri Iesu (Jesu) Christi ("In the Year of Our Lord Jesus Christ"). Look up AD, ad-, ad in Wiktionary, the free dictionary. ... A monk monking in a scriptorium. ... Dionysius Exiguus (Dennis the Little, meaning humble) (c. ... Computus (Latin for computation) is the calculation of the date of Easter in the Christian calendar. ... Medieval Latin was the form of Latin used in the Middle Ages, primarily as a medium of scholarly exchange and as the liturgical language of the medieval Roman Catholic Church, but also as a language of science, literature, law, and administration. ... The Julian calendar was a reform of the Roman calendar which was introduced by Julius Caesar in 46 BC and came into force in 45 BC (709 ab urbe condita). ... For the calendar of religious holidays and periods, see liturgical year. ...

The calendar era which it numbers is based on the traditionally reckoned year of the conception or birth of Jesus. Before Christ, abbreviated as BC or B.C., is used in the English language to denote years before the start of this epoch. A calendar era is the year numbering system used by a calendar. ... For other uses, see Annunciation (disambiguation). ... The Nativity by Petrus Christus, c. ... This article is about Jesus of Nazareth. ... This page is about the title, office or what is known in Christian theology as the Divine Person. ... The English language is a West Germanic language that originates in England. ...

Though the Anno Domini dating system was devised in 525, it was not until the 8th century that the system began to be adopted in Western Europe. According to the Catholic Encyclopedia, even popes continued to date documents according to regnal years, and usage of AD only gradually became more common in Europe from the 11th to the 14th centuries.^[4] In 1422, Portugal became the last Western European country to adopt the Anno Domini system.^[4] Regnal year: the year of the reign of a sovereign. ... A current understanding of Western Europe. ...

Year numbering using the Anno Domini system (or its related Common Era (CE) designation) is the most widespread numbering system in the world today. For decades, it has been the unofficial global standard, recognized by international institutions such as the United Nations and the Universal Postal Union. Its preeminence is due to the European colonisation of the Americas and the subsequent global spread of Western civilization with the introduction of European standards in the fields of science and administration. Its association with the Gregorian calendar was another factor which promoted the spread of the numbering system. BCE redirects here. ... UN redirects here. ... The Universal Postal Union (UPU, French: Union postale universelle) is an international organization that coordinates postal policies between member nations, and hence the world-wide postal system. ... For the calendar of religious holidays and periods, see liturgical year. ...

Traditionally, English copied Latin usage by placing the abbreviation before the year number for AD, but after the year number for BC; for example: 64 BC, but AD 2008. However, placing the AD after the year number (as in 2008 AD) is now also common. The abbreviation is also widely used after the number of a century or millennium, as in 4th century AD or 2nd millennium AD, despite the inappropriate literal combination in this case ("in the 4th century in the year of Our Lord"). The English language is a West Germanic language that originates in England. ... For other uses, see Latins and Latin (disambiguation). ... A century (From the Latin cent, one hundred) is one hundred consecutive years. ... A millennium (pl. ...

Because B.C. is an abbreviation for Before Christ, some people incorrectly conclude that A.D. must mean After Death, i.e., after the death of Jesus.^[5]

History

Further information: Calendar era

During the first six centuries of what would come to be known as the Christian era, European countries used various systems to count years. Systems in use included consular dating, imperial regnal year dating, and Creation dating. A calendar era is the year numbering system used by a calendar. ... Abbreviations: Imp. ... Regnal year: the year of the reign of a sovereign. ... Anno Mundi (AM, in the year of the world) refers to a Calendar era counting from the creation of the world. ...

Although the last non-imperial consul, Basilius, was appointed in 541 by Emperor Justinian I, later emperors through Constans II (641–668) were appointed consuls on the first January 1 after their accession. All of these emperors, except Justinian, used imperial postconsular years for all of the years of their reign alongside their regnal years.^[6] Long unused, this practice was not formally abolished until Novell xciv of the law code of Leo VI did so in 888. On January 1st of AD 541, Anicius Faustus Albinus Basilius was appointed consul in Constantinople during the Byzantine empire. ... This article is about the Roman emperor. ... Constans and his son Constantine. ... is the 1st day of the year in the Gregorian calendar. ... This follis by Leo VI bears the Byzantine Emperors official title, BASILEVS ROMEON, Emperor of the Romans; translation of text: Leo, by the grace of God, King of Romans Leo VI the Wise or the Philosopher (Greek: Λέων ΣΤ΄, Leōn VI, Armenian: [1]), (September 19, 866 – May 11, 912) was Byzantine...

The Anno Domini system was devised by a monk named Dionysius Exiguus (born in Scythia Minor) in Rome in 525. In his Easter table Dionysius equates the year AD 532 with the regnal year 284 of Emperor Diocletian. In Argumentum I attached to this table he equates the year AD 525 with the consulate of Probus Junior.^[7] He thus implies that Jesus' Incarnation occurred 525 years earlier, without stating the specific year during which his birth or conception occurred. Dionysius Exiguus (Dennis the Little, meaning humble) (c. ... Major ancient towns and colonies in Schythia Minor Scythia Minor (Greek: Μικρά Σκυθία, Mikrá Scythia) was in ancient times the region surrounded by the Danube at the north and west and the Black Sea at the east, corresponding to todays Dobruja (a large part in Romania and a smaller part in... Dionysius Exiguus Easter table was constructed in the year 525 by Dionysius Exiguus for the years 532–626. ... The anno Diocletiani era or the Diocletian era or the Era of Martyrs is a method of numbering years used by Alexandrian Christians during the fourth and fifth centuries. ... Gaius Aurelius Valerius Diocletianus (c. ...

"However, nowhere in his exposition of his table does Dionysius relate his epoch to any other dating system, whether consulate, Olympiad, year of the world, or regnal year of Augustus; much less does he explain or justify the underlying date."^[8]

Blackburn & Holford-Strevens briefly present arguments for 2 BC, 1 BC, or AD 1 as the year Dionysius intended for the Nativity or Incarnation.

Among the sources of confusion are:^[9]

• In modern times Incarnation is synonymous with conception, but some ancient writers, such as Bede, considered Incarnation to be synonymous with the Nativity
• The civil, or consular year began on January 1 but the Diocletian year began on August 29
• There were inaccuracies in the list of consuls
• There were confused summations of emperors' regnal years

Two centuries later, the Anglo-Saxon historian Bede the Venerable used another Latin term, "ante uero incarnationis dominicae tempus" ("the time before the Lord's true incarnation"), equivalent to the English "before Christ", to identify years before the first year of this era. ^[10] For other uses, see Annunciation (disambiguation). ... is the 1st day of the year in the Gregorian calendar. ... is the 241st day of the year (242nd in leap years) in the Gregorian calendar. ... For other uses, see Anglo-Saxon. ... For other uses, see Bede (disambiguation). ... For other uses, see Latins and Latin (disambiguation). ... The English language is a West Germanic language that originates in England. ...

Another calculation had been developed by the Alexandrian monk Annianus around the year AD 400, placing the Annunciation on March 25, AD 9 (Julian)—eight to ten years after the date that Dionysius was to imply. Although this Incarnation was popular during the early centuries of the Byzantine Empire, years numbered from it, an Era of Incarnation, was only used, and is still only used, in Ethiopia, accounting for the eight- or seven-year discrepancy between the Gregorian and the Ethiopian calendars. Byzantine chroniclers like Maximus the Confessor, George Syncellus and Theophanes dated their years from Annianus' Creation of the World. This era, called Anno Mundi, "year of the world" (abbreviated AM), by modern scholars, began its first year on 25 March 5492 BC. Later Byzantine chroniclers used Anno Mundi years from September 1 5509 BC, the Byzantine Era. No single Anno Mundi epoch was dominant throughout the Christian world. This article is about the city in Egypt. ... For the first-century bishop, see Anianus of Alexandria. ... For other uses, see Annunciation (disambiguation). ... is the 84th day of the year (85th in leap years) in the Gregorian calendar. ... Byzantine redirects here. ... The Ethiopian calendar (Amharic: የኢትዮጵያ ዘመን አቆጣጠር ), also called the Geez calendar, is the principal calendar used in Ethiopia and is also the liturgical year of Christians in Eritrea belonging to the Eritrean Orthodox Tewahdo Church, Eastern Catholic Church of Eritrea and Lutheran (Evangelical Church of Eritrea), where it is commonly known... Saint Maximus the Confessor (also known as Maximus the Theologian and Maximus of Constantinople) (c. ... George Syncellus (died after 810) was a Byzantine chronicler and ecclesiastic. ... Saint Theophanes the Confessor (about 758/760, Constantinople - March 17, 817 or 818, Samothrace) was an aristocratic but ascetic Byzantine monk and chronicler. ... This article is about the biblical text. ... Anno Mundi (AM, in the year of the world) refers to a Calendar era counting from the creation of the world. ... is the 84th day of the year (85th in leap years) in the Gregorian calendar. ... During the 6th millennium BC, agriculture spreads from the Balkans to Italy and Eastern Europe and from Mesopotamia to Egypt. ... is the 244th day of the year (245th in leap years) in the Gregorian calendar. ... During the 6th millennium BC, agriculture spreads from the Balkans to Italy and Eastern Europe and from Mesopotamia to Egypt. ... The Byzantine calendar was the calendar officially used by the Byzantine Empire (Eastern Roman Empire)[1] from 988 by Basil II until it was conquered in 1453. ...

Accuracy

According to Doggett, "Although scholars generally believe that Christ was born some years before A.D. 1, the historical evidence is too sketchy to allow a definitive dating".^[11] According to the Gospel of St. Matthew (2:1,16) King Herod the Great was alive when Jesus was born, and ordered the Massacre of the Innocents in response to his birth. Blackburn & Holford-Strevens fix King Herod's death shortly before Passover in 4 BC,^[12] and say that those who accept the story of the Massacre of the Innocents sometimes associate the star that led the Biblical Magi with the planetary conjunction of September 15 7 BC or Halley's comet of 12 BC; even historians who do not accept the Massacre accept the birth under Herod as a tradition older than the written gospels.^[13] The Gospel of Matthew (literally, according to Matthew; Greek, Κατά Μαθθαίον or Κατά Ματθαίον, Kata Maththaion or Kata Matthaion) is a synoptic gospel in the New Testament, one of four canonical gospels. ... Herod the Great. ... The chronology of Jesus depicts the traditional chronology established for the events of the life of Jesus by the four canonical gospels (which allude to various dates for several events). ... The Holy Innocents by Giotto di Bondone. ... The Holy Innocents by Giotto di Bondone. ... Three Kings, or Three Wise Men redirects here. ... Conjunction is a term used in positional astronomy and astrology. ... is the 258th day of the year (259th in leap years) in the Gregorian calendar. ... Comet Halley, officially designated 1P/Halley, more generally known as Halleys Comet after Edmond Halley, is a comet that can be seen every 75-76 years. ...

The Gospel of St. Luke (1:5) states that St. John the Baptist was at least conceived, if not born, under King Herod, and that Jesus was conceived while St. John's mother St. Elizabeth was in the sixth month of her pregnancy (1:26). St. Luke's Gospel also states that Jesus was born during the reign of the Emperor Augustus and while Cyrenius (or Quirinius) was the governor of Syria (2:1–2). Blackburn and Holford-Strevens^[12] indicate Cyrenius/Quirinius' governorship of Syria began in AD 6, which is incompatible with conception in 4 BC, and say that "St. Luke raises greater difficulty....Most critics therefore discard Luke".^[13] Some scholars rely on St. John's Gospel to place Christ's birth in c. 18 BC.^[13] The Gospel of Luke (literally, according to Luke; Greek, Κατά Λουκαν, Kata Loukan) is a synoptic Gospel, and the third and longest of the four canonical Gospels of the New Testament. ... For the hip-hop producer with the same name, see John the Baptist (producer). ... For other persons named Octavian, see Octavian (disambiguation). ... The Virgin and St Joseph register for the census before Governor Quirinius. ... The Virgin and St Joseph register for the census before Governor Quirinius. ... For other uses, see Gospel of John (disambiguation). ...

Popularization

The first historian or chronicler to use Anno Domini as his primary dating mechanism was Victor of Tonnenna, an African chronicler of the 6th century.^{[citation needed]} A few generations later, the Anglo-Saxon historian Bede the Venerable, who was familiar with the work of Dionysius, also used Anno Domini dating in his Ecclesiastical History of the English People, finished in 731. In this same history, he was the first to use the Latin equivalent of before Christ and established the standard for historians of no year zero, even though he used zero in his computus. Both Dionysius and Bede regarded Anno Domini as beginning at the incarnation of Jesus, but "the distinction between Incarnation and Nativity was not drawn until the late 9th century, when in some places the Incarnation epoch was identified with Christ's conception, i.e., the Annunciation on March 25" (Annunciation style).^[14] Victor of Tunnuna (d. ... For other uses, see Anglo-Saxon. ... For other uses, see Bede (disambiguation). ... For the political notion, see Year Zero (political notion). ... Computus (Latin for computation) is the calculation of the date of Easter in the Christian calendar. ... For other uses, see Annunciation (disambiguation). ... is the 84th day of the year (85th in leap years) in the Gregorian calendar. ...

On the continent of Europe, Anno Domini was introduced as the era of choice of the Carolingian Renaissance by Alcuin. This endorsement by Emperor Charlemagne and his successors popularizing the usage of the epoch and spreading it throughout the Carolingian Empire ultimately lies at the core of the system's prevalence until present times. For other uses, see Europe (disambiguation). ... Sample of Carolingian minuscule, one of the products of the Carolingian Renaissance. ... This article is about the scholar Alcuin of York. ... Charlemagne (left) and Pippin the Hunchback. ... The Franks were originally lead by dukes (military leaders) and reguli (petty kings). ... Map of Carolingian Empire The term Carolingian Empire is sometimes used to refer to the realm of the Franks under the dynasty of the Carolingians. ...

Outside the Carolingian Empire, Spain continued to date by the Era of the Caesars, or Spanish Era, which began counting from 38 BC, well into the Middle Ages,. The Era of Martyrs, which numbered years from the accession of Diocletian in 284, who launched the last yet most severe persecution of Christians, was used by the Church of Alexandria, and is still used officially by the Coptic church. It also used to be used by the Ethiopian church. Another system was to date from the crucifixion of Jesus Christ, which as early as Hippolytus and Tertullian was believed to have occurred in the consulate of the Gemini (AD 29), which appears in the occasional medieval manuscript. Most Syriac manuscripts written at the end of the 19th century still gave the date in the end-note using the "year of the Greeks" (Anno Graecorum = Seleucid era).^{[citation needed]} The Spanish era or Era of the Caesars refers to the dating system used in Hispania until the fourteenth century and the adoption of Anno Domini. ... The Spanish era or Era of the Caesars refers to the dating system used in Hispania until the fourteenth century and the adoption of Anno Domini. ... The anno Diocletiani era or the Diocletian era or the Era of Martyrs is a method of numbering years used by Alexandrian Christians during the fourth and fifth centuries. ... Gaius Aurelius Valerius Diocletianus (c. ... The Orthodox Church of Alexandria is one of the autocephalous Eastern Orthodox Churches. ... Jesus Christ in a Coptic icon. ... For other uses, see Crucifixion (disambiguation). ... Statue of Hippolytus, 3rd century. ... Quintus Septimius Florens Tertullianus, anglicised as Tertullian, (ca. ... Coin of Philip V of Macedon (ruled 221–179 BC). ...

Even though Anno Domini was in widespread use by the 9th century, Before Christ (or its equivalent) did not become widespread until the late 15th century.^[15]

Synonyms

Common Era

Main article: Common Era

Anno Domini is sometimes referred to as the Common Era, Christian Era or Current Era (abbreviated as C.E. or CE). CE is often preferred by those who desire a term unrelated to religious conceptions of time. For example, Cunningham and Starr (1998) write that "B.C.E./C.E. ... do not presuppose faith in Christ and hence are more appropriate for interfaith dialog than the conventional B.C./A.D." The People's Republic of China, founded in 1949, adopted Western years, calling that era gōngyuán (公元) which literally means Common Era. BCE redirects here. ... BCE redirects here. ...

Anno Salutis

Anno Salutis (Latin: "in the year of salvation") was the term sometimes used in place of Anno Domini until the 18th century. In all other respects it operated on the same epoch, reference date, which is the Incarnation of Jesus. It was used by fervent Christians to spread the message that the birth of Jesus saved mankind from eternal damnation. It was often used in a more elaborate form such as Anno Nostrae Salutis (meaning: "in the year of our salvation"), Anno Salutis Humanae (meaning: "in the year of the salvation of men"), or Anno Reparatae Salutis (meaning: "in the year of accomplished salvation"). For other uses, see Latins and Latin (disambiguation). ... Christ en majesté, Matthias Grünewald, 16th c. ... This article is about Jesus of Nazareth. ... For other uses, see Christian (disambiguation). ...

Numbering of years

Common usage omits year zero. This creates a problem with some scientific calculations. Accordingly, in astronomical year numbering, a zero year is added before AD 1, and the 'AD' and 'BC' designation is dropped. In keeping with 'standard decimal numbering', a minus sign '−' is added for years before year zero: so counting down from year 2 would give 2, 1, 0, −1, −2, and so on. This results in a one-year shift between the two systems (eg −1 equals 2 BC).^[16] Astronomical year numbering is based on BCE/CE (or BC/AD) year numbering, but follows normal decimal integer numbering more strictly. ...

Notes and references

Notes:

References: 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance to the Gregorian calendar. ... is the 34th day of the year in the Gregorian calendar. ... 2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance to the Gregorian calendar. ... is the 16th day of the year in the Gregorian calendar. ... For other uses, see Bede (disambiguation). ... Werner Rolevinck (1425-1502) was a Carthusian monk and wrote important chronicles on the history of westphalia and the world. ... This article is about the biblical text. ... This article is about Jesus of Nazareth. ... The recto of a broadsheet, pamphlet or any printed document is the side that is meant to be read first or the right-hand page of a folded sheet. ... Folio: In bookbinding, a sheet of paper, parchment, or other material folded in half to make two leaves in a codex. ... Sixtus IV (July 21, 1414 – August 12, 1484), born Francesco della Rovere, was Pope from 1471 to 1484. ... The verso of a broadsheet, pamphlet or any printed document is the side that is meant to be read second or the left-hand page of a folded sheet. ...

For other uses, see Bede (disambiguation). ... is the 353rd day of the year (354th in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... is the 253rd day of the year (254th in leap years) in the Gregorian calendar. ... Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ...

External links

Look up AD, Anno Domini in Wiktionary, the free dictionary.

• The Catholic Encyclopedia, s.v. "General Chronology"

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Major subjects	Time · Astronomy · Geology · Paleontology · Archaeology · History	Time Portal
Eras and Epochs	Calendar Eras: Ab urbe condita · Anno Domini / Common Era · Anno Mundi · Spanish era · Before Present · Hijri Egyptian · Sothic cycle · Hindu units of measurement · Vedic time-cycles Wikipedia does not have an article with this exact name. ... Wiktionary (a portmanteau of wiki and dictionary) is a multilingual, Web-based project to create a free content dictionary, available in over 151 languages. ... For the novel by Michael Crichton, see Timeline (novel). ... This article is about the concept of time. ... For other uses, see Astronomy (disambiguation). ... This article includes a list of works cited but its sources remain unclear because it lacks in-text citations. ... Paleontology, palaeontology or palæontology (from Greek: paleo, ancient; ontos, being; and logos, knowledge) is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. ... For referencing in Wikipedia, see Wikipedia:Citing sources. ... This article is about the study of the past in human terms. ... Image File history File links Download high resolution version (800x697, 123 KB) fr:: Montre gousset cs:: Kapesní hodinky de: Deutsch: Taschenuhr en: English: Pocket watch it: Italiano: Orologio da taschino (cipolla) es: Español: Reloj de bolsillo Template:ગુજરાતી ગુજરાતી: ખિસ્સામાં રાખવાની ઘડિયાળ ja: 日本語: 懐中時計 pl: Polski: Zegarek kieszonkowy pt: Português: Relógio de bolso... Image File history File links Portal. ... An era is a long period of time with different technical and colloquial meanings, and usages in language. ... In chronology, an epoch (or epochal date, or epochal event) means an instant in time chosen as the origin of a particular era. ... A calendar era is the year numbering system used by a calendar. ... Ab urbe condita (related with Anno urbis conditae: AUC or a. ... BCE redirects here. ... Anno Mundi (AM, in the year of the world) refers to a Calendar era counting from the creation of the world. ... The Spanish era or Era of the Caesars refers to the dating system used in Hispania until the fourteenth century and the adoption of Anno Domini. ... Before Present (BP) years are the units of time (counted backwards to the past) used to report raw radiocarbon ages and dates referenced to the BP scale origin in the year AD 1950 (identical to 1950 CE). ... The Islamic calendar or Muslim calendar (Arabic: التقويم الهجري; at-taqwÄ«m al-hijrÄ«; Persian: تقویم هجري قمری ‎ taqwÄ«m-e hejri-ye qamari; also called the Hijri calendar) is the calendar used to date events in many predominantly Muslim countries, and used by Muslims everywhere to determine the proper day on which to celebrate... The Sothic cycle or Canicular period is a period of 1461 ancient Egyptian years (of 365 days) or 1460 Julian years (averaging 365. ... Old Indian measures are still in use today, primarily for religious purposes in Hinduism and Jainism. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Regnal year: Canon of Kings · King lists · Limmu · Seleucid era · Era name: Chinese · Japanese · Korean
Calendars	Pre-Julian Roman · Original Julian · Proleptic Julian · Revised Julian Gregorian · Proleptic Gregorian · Old Style and New Style Regnal year: the year of the reign of a sovereign. ... The Canon of Kings was a dated list of kings used by ancient astronomers as a convenient means to date astronomical phenomena, such as eclipses. ... Limmu was an Assyrian eponym. ... Coin of Philip V of Macedon (ruled 221–179 BC). ... An era name was assigned as the name of each year by the leader (emperor or king) of the East Asian countries of China, Korea, Japan, and Vietnam during some portion of their history. ... For other uses, see Calendar (disambiguation) A page from the Hindu calendar 1871–1872. ... The Roman calendar changed its form several times in the time between the foundation of Rome and the fall of the Roman Empire. ... The Julian calendar was a reform of the Roman calendar which was introduced by Julius Caesar in 46 BC and came into force in 45 BC (709 ab urbe condita). ... The proleptic Julian calendar is produced by extending the Julian calendar to dates preceding its official introduction in 45 BC. Historians since Bede have traditionally represented the years preceding AD 1 as 1 BC, 2 BC, etc. ... The Revised Julian calendar is a calendar that was considered for adoption by the Eastern Orthodox churches at a synod in Istanbul in May 1923. ... For the calendar of religious holidays and periods, see liturgical year. ... The proleptic Gregorian calendar is produced by extending the Gregorian Calendar to dates preceding its official introduction in 1582. ... Old Style redirects here. ... Lunisolar · Solar · Lunar · Islamic · Chinese sexagenary cycle A lunisolar calendar is a calendar whose date indicates both the moon phase and the time of the solar year. ... A solar calendar is a calendar whose dates indicate the position of the earth on its revolution around the sun (or equivalently the apparent position of the sun moving on the celestial sphere). ... A lunar calendar is a calendar that is based on cycles of the moon phase. ... The Islamic calendar or Muslim calendar (Arabic: التقويم الهجري; at-taqwÄ«m al-hijrÄ«; Persian: تقویم هجري قمری ‎ taqwÄ«m-e hejri-ye qamari; also called the Hijri calendar) is the calendar used to date events in many predominantly Muslim countries, and used by Muslims everywhere to determine the proper day on which to celebrate... The Chinese sexagenary cycle (Chinese: ; pinyin: ) is a cyclic numeral system of 60 combinations of the two basic cycles, the ten Heavenly Stems (天干; tiāngān) and the twelve Earthly Branches (地支; dìzhÄ«). These have been traditionally used as a means of numbering days and years, not only in China... Astronomical year numbering · ISO week date
Astronomic time and techniques	Astronomical chronology · Cosmic Calendar · Ephemeris · Galactic year · Metonic cycle · Milankovitch cycles
Geologic time and techniques	Deep time · Geological history · Eon · Eras · Periods · Faunal stage Chronostratigraphy · Geochronology · Isotope geochemistry · Law of superposition · Optical dating · Samarium-neodymium dating
Archaeological techniques	Dating methodology Absolute dating · Incremental dating · Archaeomagnetic dating · Dendrochronology · Glottochronology · Ice_core · Lichenometry · Paleomagnetism · Radiocarbon dating · Radiometric dating · Tephrochronology · Thermoluminescence dating · Uranium-lead dating Astronomical year numbering is based on BCE/CE (or BC/AD) year numbering, but follows normal decimal integer numbering more strictly. ... The ISO week date system is a leap week calendar system that is part of the ISO 8601 date and time standard. ... An ephemeris (plural: ephemerides) (from the Greek word ephemeros = daily) is a device giving the positions of astronomical objects in the sky. ... // Galactic time NGC 4414, a typical spiral galaxy alike our Milky Way Galactic time, not to confuse with siderial time, is the time that is described by our spin relative to the center of the galaxy. ... The Metonic cycle or Enneadecaeteris in astronomy and calendar studies is a particular approximate common multiple of the year (specifically, the seasonal tropical year) and the synodic month. ... Milankovitch cycles are the collective effect of changes in the Earths movements upon its climate, named after Serbian civil engineer and mathematician Milutin Milanković. The eccentricity, axial tilt, and precession of the Earths orbit vary in several patterns, resulting in 100,000 year ice age cycles of the... Diagram of geological time scale. ... Deep time is the theory that Earth is billions of years old and thus had a long history of development and change. ... Geological time scale. ... In general usage, an eon (sometimes spelled aeon) is a very long period of time. ... A geologic era is a subdivision of geologic time that is a separate classification that divides the Phanerozoic Eon into three parts timeframes. ... 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Dating material drawn from the archaeological record can made by a direct study of a artifact or may be deduced by association with materials found in the context the item is drawn from or inferred by its point of discovery in the sequence relative to datable contexts. ... Absolute dating is the process of determining a specific archaeological date. ... Incremental dating techniques allow the construction of year-by-year annual chronologies, which can be fixed ( linked to the present day and thus calendar or sidereal time) or floating. ... Archaeomagnetism (adjective archaeomagnetic) is the science of how to interpret signatures of the Earths magnetic field at past times that are recorded in archaeological materials. ... The growth rings of an unknown tree species, at Bristol Zoo, England Pinus taeda Cross section showing annual rings, Cheraw, South Carolina Pine stump showing growth rings Dendrochronology or tree-ring dating is the method of scientific dating based on the analysis of tree-ring growth patterns. ... Glottochronology refers to methods in historical linguistics used to estimate the time at which languages diverged, based on the assumption that the basic (core) vocabulary of a language changes at a constant average rate. ... Ice Core sample taken from drill. ... Lichens are a symbiotic relationship between algal and fungal communities and they increase in size radially as they grow. ... Paleomagnetism refers to the study of the record of the Earths magnetic field preserved in various magnetic minerals through time. ... Radiocarbon dating is a radiometric dating method that uses the naturally occurring isotope carbon-14 (14C) to determine the age of carbonaceous materials up to about 60,000 years. ... Radiometric dating (often called radioactive dating) is a technique used to date materials, based on a comparison between the observed abundance of particular naturally occurring radioactive isotopes and their known decay rates. ... Tephrochronology is a geochronolgical technique that utilises discreet layers of tephra—volcanic ash from a single eruption— to create a chronological framework in which palaeoenvironmental or archaeological records can be placed. ... Thermoluminescence (TL) dating is the determination by means of measuring the accumulated radiation dose of the time elapsed since material containing crystalline minerals was either heated (lava, ceramics) or exposed to sunlight (sediments). ... Radiometric dating is a technique used to date materials based on a knowledge of the decay rates of naturally occurring isotopes, and the current abundances. ... Relative dating · Seriation · Stratification
Genetic techniques	Amino acid dating · Molecular clock
Related topics	Chronicle · New Chronology · Periodization · Synchronoptic view · Timeline · Year zero Circa · Floruit