Some historical calendars had "weeks" consisting of eight days.
Some historical calendars had "weeks" consisting of eight days.
In the Burmese version of Theravada Buddhism, the week has eight days. Wednesday is divided into Wednesday proper (midnight to noon) and Rahu (noon to midnight). Each day is associated with a compass direction, a planet, and a totem animal.
The ancient Etruscans developed an eight-day market week known as the nundinum around the 8th or 7th century BC. This was passed on to the Romans no later than the 6th century BC. As Rome expanded, it encountered the seven-day week and for a time attempted to include both. The popularity of the seven-day rhythm won, and the eight-day week disappeared.
The cycle of seven days – named for the sun, the moon, and the five planets visible to the naked eye – was already customary in the time of Justin Martyr, who wrote of the Christians meeting on the Day of the Sun (Sunday). [1]
Emperor Constantine eventually established the seven-day week in the Roman calendar in AD 321. [2]
The Celts used periods of darkness such as night and winter to begin their calculations of time. This meant that the first period of time in a "week" was a night, followed by a day. Further, they also counted the ending night period, giving rise to periods of time with more nights than days. In Old Irish, the term nómad is used to signify a number of days. The usage of the term varies and there are different theories about the length of time involved, but they all involve nine periods of some kind, e.g. nine days & nights; 9 × 8 hours = 72 hours = 3 days & nights; 9 × 9 hours ~ 3½ days; 9 × 12 hours = 4½ days. [3] [4] Joseph Loth noted the frequency of the expression co cend nomaide (“to the end of a nómad”) in the literature—sometimes replaced by nóilaíthe (“nine days”)—and how the division fitted neatly into a sidereal month of 27 nights. [4] In Welsh, the word for "week" is wythnos which literally means "eight-nights" since it was historically considered that a week started and ended with a period of night bracketing seven days. Similarly the word for "fortnight", pythefnos, literally means "fifteen-nights". [5] [6] The Irish word for "fortnight", coicís , also relates to the number fifteen.
A day is the time period of a full rotation of the Earth with respect to the Sun. On average, this is 24 hours, 1440 minutes, or 86,400 seconds. In everyday life, the word "day" often refers to a solar day, which is the length between two solar noons or times the Sun reaches the highest point. The word "day" may also refer to daytime, a time period when the location receives direct and indirect sunlight. On Earth, as a location passes through its day, it experiences morning, noon, afternoon, evening, and night. The effect of a day is vital to many life processes, which is called the circadian rhythm.
A week is a unit of time equal to seven days. It is the standard time period used for short cycles of days in most parts of the world. The days are often used to indicate common work days and rest days, as well as days of worship. Weeks are often mapped against yearly calendars, but are typically not the basis for them, as weeks are not based on astronomy.
Saturday is the day of the week between Friday and Sunday. No later than the 2nd century, the Romans named Saturday diēs Sāturnī for the planet Saturn, which controlled the first hour of that day, according to Vettius Valens. The day's name was introduced into West Germanic languages and is recorded in the Low German languages such as Middle Low German satersdach, saterdach, Middle Dutch saterdag and Old English Sæternesdæġ, Sæterndæġ or Sæterdæġ.
Wednesday is the day of the week between Tuesday and Thursday. According to international standard ISO 8601, it is the third day of the week. In countries which have Friday as their holiday, Wednesday is the fifth day of the week. In countries which use the Sunday-first convention, and in both the Islamic and Jewish calendars, Wednesday is the fourth day of the week.
A fortnight is a unit of time equal to 14 days. The word derives from the Old English term fēowertīene niht, meaning "fourteen nights".
In the practice of Christianity, canonical hours mark the divisions of the day in terms of fixed times of prayer at regular intervals. A book of hours, chiefly a breviary, normally contains a version of, or selection from, such prayers.
Noon is 12 o'clock in the daytime. It is written as 12 noon, 12:00 m., 12 p.m., 12 pm, or 12:00 or 1200 . Solar noon is the time when the Sun appears to contact the local celestial meridian. This is when the Sun reaches its apparent highest point in the sky, at 12 noon apparent solar time and can be observed using a sundial. The local or clock time of solar noon depends on the longitude and date, with Daylight Saving Time tending to place solar noon closer to 1:00pm.
The 12-hour clock is a time convention in which the 24 hours of the day are divided into two periods: a.m. and p.m.. Each period consists of 12 hours numbered: 12, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11. The 12-hour clock was developed from the second millennium BC and reached its modern form in the 16th century AD.
Midnight sun is a natural phenomenon that occurs in the summer months in places north of the Arctic Circle or south of the Antarctic Circle, when the Sun remains visible at the local midnight. When midnight sun is seen in the Arctic, the Sun appears to move from left to right, but in Antarctica the equivalent apparent motion is from right to left. This occurs at latitudes from 65°44' to 90° north or south, and does not stop exactly at the Arctic Circle or the Antarctic Circle, due to refraction.
Compline, also known as Complin, Night Prayer, or the Prayers at the End of the Day, is the final prayer liturgy of the day in the Christian tradition of canonical hours, which are prayed at fixed prayer times.
Matins is a canonical hour in Christian liturgy, originally sung during the darkness of early morning.
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.
In a bar, a last call is an announcement made shortly before the bar closes for the night, informing patrons of their last chance to buy alcoholic beverages. There are various means to make the signal, like ringing a bell, flashing the lights, or announcing verbally.
In many languages, the names given to the seven days of the week are derived from the names of the classical planets in Hellenistic astronomy, which were in turn named after contemporary deities, a system introduced by the Sumerians and later adopted by the Babylonians from whom the Roman Empire adopted the system during Late Antiquity. In some other languages, the days are named after corresponding deities of the regional culture, beginning either with Sunday or with Monday. The seven-day week was adopted in early Christianity from the Hebrew calendar, who copied it from the Babylonians and gradually replaced the Roman nundinal cycle. Sunday remained the first day of the week, being considered the day of the sun god Sol Invictus and the Lord's Day, while the Jewish sabbath remained the seventh. Emperor Constantine adopted the seven-day week for official use in 321 CE, making the Day of the Sun a legal holiday.
Terce is a canonical hour of the Divine Office. It consists mainly of psalms and is held around 9 a.m. Its name comes from Latin and refers to the third hour of the day after dawn. With Prime, Sext, None and Compline it belongs to the so-called "Little hours".
The Copts, who belong mostly to the Coptic Orthodox Church, observe fasting periods according to the Coptic calendar. These fasting periods are exceeded by no other Christian community except the Orthodox Tewahedo. Out of the 365 days of the year, Copts often fast between 210 to 240 days. This means that Copts abstain from all animal products for up to two-thirds of each year. Coptic Orthodox fasts have evolved over time to become more lengthier and severer. A lifestyle involving such fasts may have contributed to the pacifist mindset of the Coptic people for centuries.
Date and time notation in Japan has historically followed the Japanese calendar and the nengō system of counting years. At the beginning of the Meiji period, Japan switched to the Gregorian calendar on Wednesday, 1 January 1873, but for much domestic and regional government paperwork, the Japanese year is retained. Japanese people and businesses have also adopted various conventions in accordance with their use of kanji, the widespread use of passenger trains, and other aspects of daily life.
In Roman timekeeping, a day was divided into periods according to the available technology. Initially the day was divided into two parts: the ante meridiem and the post meridiem. With the advent of the sundial circa 263 BC, the period of the natural day from sunrise to sunset was divided into twelve hours.
The shift plan, rota or roster is the central component of a shift schedule in shift work. The schedule includes considerations of shift overlap, shift change times and alignment with the clock, vacation, training, shift differentials, holidays, etc. The shift plan determines the sequence of work (W) and free (F) days within a shift system.
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