Gregor Johann Mendel was a scientist, Augustinian friar and abbot of St. Thomas' Abbey in Brno, Margraviate of Moravia. Mendel was born in a German-speaking family in the Silesian part of the Austrian Empire and gained posthumous recognition as the founder of the modern science of genetics. Though farmers had known for millennia that crossbreeding of animals and plants could favor certain desirable traits, Mendel's pea plant experiments conducted between 1856 and 1863 established many of the rules of heredity, now referred to as the laws of Mendelian inheritance. Mendel worked with seven characteristics of pea plants: plant height, pod shape and color, seed shape and color, flower position and color. Taking seed color as an example, Mendel showed that when a true-breeding yellow pea and a true-breeding green pea were cross-bred their offspring always produced yellow seeds. However, in the next generation, the green peas reappeared at a ratio of 1 green to 3 yellow. To explain this phenomenon, Mendel coined the terms “recessive” and “dominant” in reference to certain traits.
He published his work in 1866, demonstrating the actions of invisible “factors”—now called genes—in predictably determining the traits of an organism. The profound significance of Mendel's work was not recognized until the turn of the 20th century with the rediscovery of his laws. Erich von Tschermak, Hugo de Vries, Carl Correns and William Jasper Spillman independently verified several of Mendel's experimental findings, ushering in the modern age of genetics. Mendel was born into a German-speaking family in Hynčice, at the Moravian-Silesian border, Austrian Empire, he was the son of Anton and Rosine Mendel and had one older sister and one younger, Theresia. They lived and worked on a farm, owned by the Mendel family for at least 130 years. During his childhood, Mendel worked as a gardener and studied beekeeping; as a young man, he attended gymnasium in Opava. He had to take four months off during his gymnasium studies due to illness. From 1840 to 1843, he studied practical and theoretical philosophy and physics at the Philosophical Institute of the University of Olomouc, taking another year off because of illness.
He struggled financially to pay for his studies, Theresia gave him her dowry. He helped support her three sons, two of whom became doctors, he became a friar in part because it enabled him to obtain an education without having to pay for it himself. As the son of a struggling farmer, the monastic life, in his words, spared him the "perpetual anxiety about a means of livelihood." He was given the name Gregor. When Mendel entered the Faculty of Philosophy, the Department of Natural History and Agriculture was headed by Johann Karl Nestler who conducted extensive research of hereditary traits of plants and animals sheep. Upon recommendation of his physics teacher Friedrich Franz, Mendel entered the Augustinian St Thomas's Abbey in Brno and began his training as a priest. Born Johann Mendel, he took the name Gregor upon entering religious life. Mendel worked as a substitute high school teacher. In 1850, he failed the oral part, the last of three parts, of his exams to become a certified high school teacher.
In 1851, he was sent to the University of Vienna to study under the sponsorship of Abbot C. F. Napp so that he could get more formal education. At Vienna, his professor of physics was Christian Doppler. Mendel returned to his abbey in 1853 as a teacher, principally of physics. In 1856, he again failed the oral part. In 1867, he replaced Napp as abbot of the monastery. After he was elevated as abbot in 1868, his scientific work ended, as Mendel became overburdened with administrative responsibilities a dispute with the civil government over its attempt to impose special taxes on religious institutions. Mendel died on 6 January 1884, at the age of 61, in Brno, Austria-Hungary, from chronic nephritis. Czech composer Leoš Janáček played the organ at his funeral. After his death, the succeeding abbot burned all papers in Mendel's collection, to mark an end to the disputes over taxation. Gregor Mendel, known as the "father of modern genetics", was inspired by both his professors at the Palacký University and his colleagues at the monastery to study variation in plants.
In 1854, Napp authorized Mendel to carry out a study in the monastery's 2 hectares experimental garden, planted by Napp in 1830. Unlike Nestler, who studied hereditary traits in sheep, Mendel used the common edible pea and started his experiments in 1856. After initial experiments with pea plants, Mendel settled on studying seven traits that seemed to be inherited independently of other traits: seed shape, flower color, seed coat tint, pod shape, unripe pod color, flower location, plant height, he first focused on seed shape, either angular or round. Between 1856 and 1863 Mendel cultivated and tested some 28,000 plants, the majority of which were pea plants; this study showed that, when true-breeding different varieties were crossed to each other, in the second generation, one in four pea pl
Calendar reform or calendrical reform, is any significant revision of a calendar system. The term sometimes is used instead for a proposal to switch to a different calendar design; the prime objective of a calendar is to unambiguously identify any day throughout history by a specific date. Periods that contain multiple days, like weeks and years, are secondary features of a calendar for convenience. Most cultures adopt a primary dating system, but different cultures have always needed to align multiple calendars with each other, because they coexisted in the same space or had established trading relations. Once specified, a calendar design cannot be altered without becoming a new one, but if a design is sufficiently close to the one used before in the local calendar system, switching to it and hence a calendar reform is possible without disruption; some design changes, will yield date identifiers different from the previous design for some days in the distant past or future. The calendar system must clarify whether dates are changed to the new design retroactively or whether the design in use and there shall be respected.
Calendar schisms happen if not all cultures that adopted a common calendar system before perform a calendar reform at the same time. If date identifiers are similar but different and mistakes are unavoidable. Most calendars have several rules which could be altered by reform: Whether and how days are grouped into subdivisions such as months and weeks, days outside those subdivisions, if any. Which years are common years and how they differ. Numbering of years, selection of the epoch, the issue of year zero. Start of the year. If a week is retained, the start and names of its days. Start of the day. If months are retained, number and names of months. Special days and periods. Alignment with social cycles. Alignment with astronomical cycles. Alignment with biological cycles. Literal notation of dates. Most calendar reforms have been made in order to synchronize the calendar with the astronomical year and/or the synodic month in lunar or lunisolar calendars. Most reforms for calendars have been to make them more accurate.
This has happened to various lunar and lunisolar calendars, the Julian calendar when it was altered to the Gregorian calendar. The fundamental problems of the calendar are that the astronomical year has neither a whole number of days nor a whole number of lunar months; such remainders could accumulate from one period to the next, thereby driving the cycles out of synch. A typical solution to force synchronization is'intercalation'; this means adding an extra day into the cycle. An alternative approach is to ignore the mismatch and let the cycles continue to drift apart; the general approaches include: The lunar calendar, which fits days into the cycle of lunar months, adding an extra day when needed, while ignoring the annual solar cycle of the seasons. The solar calendar, which fits artificial months into the year, adding an extra day into one month when needed, while ignoring the lunar cycle of new/full moons; the lunisolar calendar, which keeps both the lunar and solar cycles, adding an extra month into the year when needed.
An obvious disadvantage of the lunisolar method of inserting a whole extra month is the large irregularity of the length of the year from one to the next. The simplicity of a lunar calendar has always been outweighed by its inability to track the seasons, a solar calendar is used in conjunction to remedy this defect. Identifying the lunar cycle month requires straightforward observation of the Moon on a clear night. However, identifying seasonal cycles requires much more methodical observation of stars or a device to track solar day-to-day progression, such as that established at places like Stonehenge. After centuries of empirical observations, the theoretical aspects of calendar construction could become more refined, enabling predictions that identified the need for reform. There have been 50 to 100 reforms of the traditional Chinese calendar over 2500 years, most of which were intended to better fit the calendar months to astronomical lunations and to more add the extra month so that the regular months maintain their proper seasonal positions though each seasonal marker can occur anywhere within its month.
There have been at least four similar reforms of the lunisolar version of the Hindu calendar, all intended to make the month a better match to the lunation and to make the year a better fit to the sidereal year. There have been reforms of the solar version of the Hindu calendar which changed the distribution of the days in each month to better match the length of time that the Sun spends in each sidereal zodiacal sign; the same applies to the Buddhist calendar. The first millennium reform of the Hebrew calendar changed it from an observational calendar into a calculated calendar; the Islamic calendar was a reform of the preceding lunisolar calendar which divorced it from the solar year. Another reform was performed in Seljuk Persia by Omar Khayyam and others, developing the computed Jalali calendar; when Julius Caesar
A calendar is a system of organizing days for social, commercial or administrative purposes. This is done by giving names to periods of time days, weeks and years. A date is the designation of a specific day within such a system. A calendar is a physical record of such a system. A calendar can mean a list of planned events, such as a court calendar or a or chronological list of documents, such as a calendar of wills. Periods in a calendar are though not synchronised with the cycle of the sun or the moon; the most common type of pre-modern calendar was the lunisolar calendar, a lunar calendar that adds one intercalary month to remain synchronised with the solar year over the long term. The term calendar is taken from calendae, the term for the first day of the month in the Roman calendar, related to the verb calare "to call out", referring to the "calling" of the new moon when it was first seen. Latin calendarium meant "account book, register"; the Latin term was adopted in Old French as calendier and from there in Middle English as calender by the 13th century.
A calendar can be on paper or electronic device. The course of the sun and the moon are the most salient natural recurring events useful for timekeeping, thus in pre-modern societies worldwide lunation and the year were most used as time units; the Roman calendar contained remnants of a ancient pre-Etruscan 10-month solar year. The first recorded physical calendars, dependent on the development of writing in the Ancient Near East, are the Bronze Age Egyptian and Sumerian calendars. A large number of Ancient Near East calendar systems based on the Babylonian calendar date from the Iron Age, among them the calendar system of the Persian Empire, which in turn gave rise to the Zoroastrian calendar and the Hebrew calendar. A great number of Hellenic calendars developed in Classical Greece, in the Hellenistic period gave rise to both the ancient Roman calendar and to various Hindu calendars. Calendars in antiquity were lunisolar, depending on the introduction of intercalary months to align the solar and the lunar years.
This was based on observation, but there may have been early attempts to model the pattern of intercalation algorithmically, as evidenced in the fragmentary 2nd-century Coligny calendar. The Roman calendar was reformed by Julius Caesar in 45 BC; the Julian calendar was no longer dependent on the observation of the new moon but followed an algorithm of introducing a leap day every four years. This created a dissociation of the calendar month from the lunation; the Islamic calendar is based on the prohibition of intercalation by Muhammad, in Islamic tradition dated to a sermon held on 9 Dhu al-Hijjah AH 10. This resulted in an observation-based lunar calendar that shifts relative to the seasons of the solar year; the first calendar reform of the early modern era was the Gregorian calendar, introduced in 1582 based on the observation of a long-term shift between the Julian calendar and the solar year. There have been a number of modern proposals for reform of the calendar, such as the World Calendar, International Fixed Calendar, Holocene calendar, the Hanke-Henry Permanent Calendar.
Such ideas are mooted from time to time but have failed to gain traction because of the loss of continuity, massive upheaval in implementation, religious objections. A full calendar system has a different calendar date for every day, thus the week cycle is by itself not a full calendar system. The simplest calendar system just counts time periods from a reference date; this applies for Unix Time. The only possible variation is using a different reference date, in particular, one less distant in the past to make the numbers smaller. Computations in these systems are just a matter of subtraction. Other calendars have one larger units of time. Calendars that contain one level of cycles: week and weekday – this system is not common year and ordinal date within the year, e.g. the ISO 8601 ordinal date systemCalendars with two levels of cycles: year and day – most systems, including the Gregorian calendar, the Islamic calendar, the Solar Hijri calendar and the Hebrew calendar year and weekday – e.g. the ISO week dateCycles can be synchronized with periodic phenomena: Lunar calendars are synchronized to the motion of the Moon.
Solar calendars are based on perceived seasonal changes synchronized to the apparent motion of the Sun. Lunisolar calendars are based on a combination of both solar and lunar reckonings; the week cycle is an example of one, not synchronized to any external phenomenon. A calendar includes more than one type of cycle, or has both cyclic and non-cyclic elements. Most calendars incorporate more complex cycles. For example, the vast majority of them track years, months and days; the seven-day week is universal, though its use varies. It has run uninterrupted for millennia. Solar calendars assign a date to each solar day. A day may consist of the period between sunrise and sunset, with
Tycho Brahe was a Danish nobleman and writer known for his accurate and comprehensive astronomical and planetary observations. He was born in the Danish peninsula of Scania. Well known in his lifetime as an astronomer and alchemist, he has been described as "the first competent mind in modern astronomy to feel ardently the passion for exact empirical facts." His observations were some five times more accurate than the best available observations at the time. An heir to several of Denmark's principal noble families, he received a comprehensive education, he took an interest in the creation of more accurate instruments of measurement. As an astronomer, Tycho worked to combine what he saw as the geometrical benefits of the Copernican system with the philosophical benefits of the Ptolemaic system into his own model of the universe, the Tychonic system, his system saw the Moon as orbiting Earth, the planets as orbiting the Sun, but erroneously considered the Sun to be orbiting the Earth. Furthermore, he was the last of the major naked-eye astronomers, working without telescopes for his observations.
In his De nova stella of 1573, he refuted the Aristotelian belief in an unchanging celestial realm. His precise measurements indicated that "new stars", in particular that of 1572, lacked the parallax expected in sublunar phenomena and were therefore not tailless comets in the atmosphere as believed but were above the atmosphere and beyond the moon. Using similar measurements he showed that comets were not atmospheric phenomena, as thought, must pass through the immutable celestial spheres. King Frederick II granted Tycho an estate on the island of Hven and the funding to build Uraniborg, an early research institute, where he built large astronomical instruments and took many careful measurements, Stjerneborg, when he discovered that his instruments in Uraniborg were not sufficiently steady. On the island he founded manufactories, such as a paper mill, to provide material for printing his results. After disagreements with the new Danish king, Christian IV, in 1597, he went into exile, was invited by the Bohemian king and Holy Roman Emperor Rudolph II to Prague, where he became the official imperial astronomer.
He built an observatory at Benátky nad Jizerou. There, from 1600 until his death in 1601, he was assisted by Johannes Kepler, who used Tycho's astronomical data to develop his three laws of planetary motion. Tycho's body has been exhumed twice, in 1901 and 2010, to examine the circumstances of his death and to identify the material from which his artificial nose was made; the conclusion was that his death was caused by a burst bladder, not by poisoning as had been suggested, that the artificial nose was more made of brass than silver or gold, as some had believed in his time. Tycho was born as heir to several of Denmark's most influential noble families and in addition to his immediate ancestry with the Brahe and the Bille families, he counted the Rud, Trolle and Rosenkrantz families among his ancestors. Both of his grandfathers and all of his great grandfathers had served as members of the Danish king's Privy Council, his paternal grandfather and namesake Thyge Brahe was the lord of Tosterup Castle in Scania and died in battle during the 1523 Siege of Malmö during the Lutheran Reformation Wars.
His maternal grandfather Claus Bille, lord to Bohus Castle and a second cousin of Swedish king Gustav Vasa, participated in the Stockholm Bloodbath on the side of the Danish king against the Swedish nobles. Tycho's father Otte Brahe, like his father a royal Privy Councilor, married Beate Bille, herself a powerful figure at the Danish court holding several royal land titles. Both parents are buried under the floor of Kågeröd Church, four kilometres east of Knutstorp. Tycho was born at his family's ancestral seat of Knutstorp Castle, about eight kilometres north of Svalöv in Danish Scania, he was the oldest of 12 siblings. His twin brother died before being baptized. Tycho wrote an ode in Latin to his dead twin, printed in 1572 as his first published work. An epitaph from Knutstorp, but now on a plaque near the church door, shows the whole family, including Tycho as a boy; when he was only two years old Tycho was taken away to be raised by his uncle Jørgen Thygesen Brahe and his wife Inger Oxe who were childless.
It is unclear why Otte Brahe reached this arrangement with his brother, but Tycho was the only one of his siblings not to be raised by his mother at Knutstorp. Instead, Tycho was raised at Jørgen Brahe's estate at Tosterup and at Tranekær on the island of Langeland, at Næsbyhoved Castle near Odense, again at the Castle of Nykøbing on the island of Falster. Tycho wrote that Jørgen Brahe "raised me and generously provided for me during his life until my eighteenth year. From ages 6 to 12, Tycho attended Latin school in Nykøbing. At age 12, on 19 April 1559, Tycho began studies at the University of Copenhagen. There, following his uncle's wishes, he studied law, but studied a variety of other subjects and became interested in astronomy. At the University, Aristotle was a staple of scientific theory, Tycho received a thorough training in Aristotelian physics and cosmology, he experienced the solar eclipse of 21 August 1560, was impressed by the fact that it had been pre
Carl Gustav Jung was a Swiss psychiatrist and psychoanalyst who founded analytical psychology. Jung's work was influential in the fields of psychiatry, archaeology, literature and religious studies. Jung worked as a research scientist under Eugen Bleuler. During this time, he came to the attention of the founder of psychoanalysis; the two men conducted a lengthy correspondence and collaborated, for a while, on a joint vision of human psychology. Freud saw the younger Jung as the heir he had been seeking to take forward his "new science" of psychoanalysis and to this end secured his appointment as President of his newly founded International Psychoanalytical Association. Jung's research and personal vision, made it impossible for him to bend to his older colleague's doctrine, a schism became inevitable; this division was painful for Jung, it was to have historic repercussions lasting well into the modern day. Among the central concepts of analytical psychology is individuation—the lifelong psychological process of differentiation of the self out of each individual's conscious and unconscious elements.
Jung considered it to be the main task of human development. He created some of the best known psychological concepts, including synchronicity, archetypal phenomena, the collective unconscious, the psychological complex, extraversion and introversion. Jung was an artist and builder as well as a prolific writer. Many of his works were not published until after his death and some are still awaiting publication. Carl Gustav Jung was born in Kesswil, in the Swiss canton of Thurgau, on 26 July 1875 as the second and first surviving son of Paul Achilles Jung and Emilie Preiswerk, their first child, born in 1873, was a boy named Paul. Being the youngest son of a noted Basel physician of German descent called Karl Gustav Jung, whose hopes of achieving a fortune never materialised, Paul Jung did not progress beyond the status of an impoverished rural pastor in the Swiss Reformed Church. Emilie was the youngest child of a distinguished Basel churchman and academic, Samuel Preiswerk, his second wife. Preiswerk was antistes, the title given to the head of the Reformed clergy in the city, as well as a Hebraist and editor, who taught Paul Jung as his professor of Hebrew at Basel University.
When Jung was six months old, his father was appointed to a more prosperous parish in Laufen, but the tension between his parents was growing. Emilie Jung was an depressed woman. Although she was normal during the day, Jung recalled that at night his mother became strange and mysterious, he reported that one night he saw a faintly luminous and indefinite figure coming from her room with a head detached from the neck and floating in the air in front of the body. Jung had a better relationship with his father. Jung's mother left Laufen for several months of hospitalization near Basel for an unknown physical ailment, his father took the boy to be cared for by Emilie Jung's unmarried sister in Basel, but he was brought back to his father's residence. Emilie Jung's continuing bouts of absence and depression troubled her son and caused him to associate women with "innate unreliability", whereas "father" meant for him reliability but powerlessness. In his memoir, Jung would remark; these early impressions were revised: I have trusted men friends and been disappointed by them, I have mistrusted women and was not disappointed."
After three years of living in Laufen, Paul Jung requested a transfer. In 1879 he was called to Kleinhüningen, next to Basel, where his family lived in a parsonage of the church; the relocation lifted her melancholy. When he was nine years old, Jung's sister Johanna Gertrud was born. Known in the family as "Trudi", she became a secretary to her brother. Jung was a introverted child. From childhood, he believed that, like his mother, he had two personalities—a modern Swiss citizen and a personality more suited to the 18th century. "Personality Number 1", as he termed it, was a typical schoolboy living in the era of the time. "Personality Number 2" was a dignified and influential man from the past. Although Jung was close to both parents, he was disappointed by his father's academic approach to faith. A number of childhood memories made lifelong impressions on him; as a boy, he carved a tiny mannequin into the end of the wooden ruler from his pencil case and placed it inside the case. He added a stone, which he had painted into upper and lower halves, hid the case in the attic.
Periodically, he would return to the mannequin bringing tiny sheets of paper with messages inscribed on them in his own secret language. He reflected that this ceremonial act brought him a feeling of inner peace and security. Years he discovered similarities between his personal experience and the practices associated with totems in indigenous cultures, such as the collection of soul-stones near Arlesheim or the tjurungas of Australia, he concluded that his intuitive ceremonial act was an unconscious ritual, which he had practiced in a way, strikingly similar to those in distant locations which he, as a young boy, knew nothing about. His observations about symbols and the collective unconscious were inspired, in part, by these early experi
Judaism is the religion of the Jewish people. It is an ancient, Abrahamic religion with the Torah as its foundational text, it encompasses the religion and culture of the Jewish people. Judaism is considered by religious Jews to be the expression of the covenant that God established with the Children of Israel. Judaism encompasses a wide body of texts, theological positions, forms of organization; the Torah is part of the larger text known as the Tanakh or the Hebrew Bible, supplemental oral tradition represented by texts such as the Midrash and the Talmud. With between 14.5 and 17.4 million adherents worldwide, Judaism is the tenth largest religion in the world. Within Judaism there are a variety of movements, most of which emerged from Rabbinic Judaism, which holds that God revealed his laws and commandments to Moses on Mount Sinai in the form of both the Written and Oral Torah; this assertion was challenged by various groups such as the Sadducees and Hellenistic Judaism during the Second Temple period.
Modern branches of Judaism such as Humanistic Judaism may be nontheistic. Today, the largest Jewish religious movements are Orthodox Judaism, Conservative Judaism, Reform Judaism. Major sources of difference between these groups are their approaches to Jewish law, the authority of the Rabbinic tradition, the significance of the State of Israel. Orthodox Judaism maintains that the Torah and Jewish law are divine in origin and unalterable, that they should be followed. Conservative and Reform Judaism are more liberal, with Conservative Judaism promoting a more traditionalist interpretation of Judaism's requirements than Reform Judaism. A typical Reform position is that Jewish law should be viewed as a set of general guidelines rather than as a set of restrictions and obligations whose observance is required of all Jews. Special courts enforced Jewish law. Authority on theological and legal matters is not vested in any one person or organization, but in the sacred texts and the rabbis and scholars who interpret them.
The history of Judaism spans more than 3,000 years. Judaism has its roots as an organized religion in the Middle East during the Bronze Age. Judaism is considered one of the oldest monotheistic religions; the Hebrews and Israelites were referred to as "Jews" in books of the Tanakh such as the Book of Esther, with the term Jews replacing the title "Children of Israel". Judaism's texts and values influenced Abrahamic religions, including Christianity and the Baha'i Faith. Many aspects of Judaism have directly or indirectly influenced secular Western ethics and civil law. Hebraism was just as important a factor in the ancient era development of Western civilization as Hellenism, Judaism, as the background of Christianity, has shaped Western ideals and morality since Early Christianity. Jews are an ethnoreligious group including those born Jewish, in addition to converts to Judaism. In 2015, the world Jewish population was estimated at about 14.3 million, or 0.2% of the total world population. About 43% of all Jews reside in Israel and another 43% reside in the United States and Canada, with most of the remainder living in Europe, other minority groups spread throughout Latin America, Asia and Australia.
Unlike other ancient Near Eastern gods, the Hebrew God is portrayed as solitary. Judaism thus begins with ethical monotheism: the belief that God is one and is concerned with the actions of mankind. According to the Tanakh, God promised Abraham to make of his offspring a great nation. Many generations he commanded the nation of Israel to love and worship only one God, he commanded the Jewish people to love one another. These commandments are but two of a large corpus of commandments and laws that constitute this covenant, the substance of Judaism. Thus, although there is an esoteric tradition in Judaism, Rabbinic scholar Max Kadushin has characterized normative Judaism as "normal mysticism", because it involves everyday personal experiences of God through ways or modes that are common to all Jews; this is played out through the observance of the Halakha and given verbal expression in the Birkat Ha-Mizvot, the short blessings that are spoken every time a positive commandment is to be fulfilled.
The ordinary, everyday things and occurrences we have, constitute occasions for the experience of God. Such things as one's daily sustenance, the day itself, are felt as manifestations of God's loving-kindness, calling for the Berakhot. Kedushah, nothing else than the imitation of God, is concerned with daily conduct, with being gracious and merciful, with keeping oneself from defilement by idolatry and the shedding of blood; the Birkat Ha-Mitzwot evokes the consciousness of holiness at a rabbinic rite, but the objects employed in the majority of these rites are non-holy and of general character, while the several holy objects are non-theurgic. And not only do ordinary things and occurrences bring with them the experience of God. Everything that happens to a man evokes that exp
The Ethiopian calendar or Eritrean calendar is the principal calendar used in Ethiopia and 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, the Coptic Orthodox Church of Alexandria, Ethiopian-Eritrean Evangelicalism. It is a solar calendar which in turn derives from the Egyptian calendar, but like the Julian calendar, it adds a leap day every four years without exception, begins the year on August 29 or August 30 in the Julian calendar. A gap of 7–8 years between the Ethiopian and Gregorian calendars results from an alternative calculation in determining the date of the Annunciation. Like the Coptic calendar, the Ethiopic calendar has 12 months of 30 days plus 5 or 6 epagomenal days, which comprise a thirteenth month; the Ethiopian months begin on the same days as those of the Coptic calendar, but their names are in Ge'ez. A 6th epagomenal day is added every 4 years, without exception, on August 29 of the Julian calendar, 6 months before the corresponding Julian leap day.
Thus the first day of the Ethiopian year, 1 Mäskäräm, for years between 1900 and 2099, is September 11. However, it falls on September 12 in years before the Gregorian leap year. Enkutatash is the word for the Ethiopian New Year in Amharic, the official language of Ethiopia, while it is called Ri'se Awde Amet in Ge'ez, the term preferred by the Ethiopian & Eritrean Orthodox Tewahedo Churchs, it occurs on September 11th in the Gregorian Calendar. The Ethiopian Calendar Year 1998 Amätä Məhrät began on the Gregorian Calendar Year on September 11th, 2005. However, the Ethiopian Years 1992 and 1996 began on the Gregorian Dates of'September 12th 1999' and'2003' respectively; this date correspondence applies for the Gregorian years 1900 to 2099. The Ethiopian leap year is every four without exception, while Gregorian centurial years are only leap years when divisible by 400; as the Gregorian year 2000 is a leap year, the current correspondence lasts two centuries instead. The start of the Ethiopian year falls on August 30th.
This date corresponds to the Old-Style Julian Calendar. This deviation between the Julian and the Gregorian Calendar will increase with the passing of the time. You can observe the real start date in the future centuries in a Gregorian to Ethiopian Date Converter. To indicate the year and followers of the Eritrean churches today use the Incarnation Era, which dates from the Annunciation or Incarnation of Jesus on March 25, AD 9, as calculated by Annianus of Alexandria c. 400. Meanwhile, Europeans adopted the calculations made by Dionysius Exiguus in AD 525 instead, which placed the Annunciation 8 years earlier than had Annianus; this causes the Ethiopian year number to be 8 years less than the Gregorian year number from January 1 until September 10 or 11 7 years less for the remainder of the Gregorian year. In the past, a number of other eras for numbering years were widely used in Ethiopia and the Kingdom of Aksum; the most important era – once used by the Eastern Christianity, still used by the Coptic Orthodox Church of Alexandria – was the Era of Martyrs known as the Diocletian Era, or the era of Diocletian and the Martyrs, whose first year began on August 29, 284.
Respective to the Gregorian and Julian New Year's Days, 31⁄2 to 4 months the difference between the Era of Martyrs and the Anni Domini is 285 years. This is because in AD 525, Dionysius Exiguus decided to add 15 Metonic cycles to the existing 13 Metonic cycles of the Diocletian Era to obtain an entire 532 year medieval Easter cycle, whose first cycle ended with the year Era of Martyrs 247 equal to year DXXXI, it is because 532 is the product of the Metonic cycle of 19 years and the solar cycle of 28 years. Around AD 400, an Alexandrine monk called Panodoros fixed the Alexandrian Era, the date of creation, on 29 August 5493 BC. After the 6th century AD, the era was used by Ethiopian chronologists; the twelfth 532 year-cycle of this era began on 29 August AD 360, so 4×19 years after the Era of Martyrs. Bishop Anianos preferred the Annunciation style as 25 March, thus he shifted the Panodoros era by about six months, to begin on 25 March 5492 BC. In the Ethiopian calendar this was equivalent to 15 Magabit 5501 B.
C.. The Anno Mundi era remained in usage until the late 19th century; the 4 year leap-year cycle is associated with the four Evangelists: the first year after an Ethiopian leap year is named the John-year, followed by the Matthew-year, the Mark-year. The year with the 6th epagomenal day is traditionally designated as the Luke-year. There are no exceptions to the 4 year leap-year cycle, like the Julian calendar but unlike the Gregorian calendar; these dates are valid only from March 1900 to February 2100. This is because 1900 and 2100 are not leap years in the Gregorian calendar, while they are still leap year