Noon (also midday or noon time) is 12 o'clock in the daytime, as opposed to midnight. The term 12 p.m. (for post meridiem, and also written as 12 pm or similar variations thereof) is sometimes used for noon.

Solar noon is the time when the Sun appears to contact the local celestial meridian. This is when the Sun apparently reaches its highest point in the sky, at 12 noon apparent solar time. The local or clock time of solar noon depends on the longitude and date.[1]

In many cultures in the Northern Hemisphere, noon had ancient geographic associations with the direction "south" (as did midnight with "north" in some cultures). Remnants of the noon = south association are preserved in the words for noon in French (Midi) and Italian (Mezzogiorno), both of which also refer to the southern parts of the respective countries. Modern Russian, Polish, Belarusian, Ukrainian, and Serbian go a step farther, with the words for noon (полдень, południe, поўдзень, південь, пoднe – literally "half-day") also meaning "south" and the words for "midnight" (północ, поўнач, північ, пoнoħ – literally "half-night", as with English mid(dle) meaning "half") also meaning "north".

Noon India Kerala
The Sun at noon, as viewed from Kerala, India


Big Brum from Hill Street - - 499120
A clock tower in Birmingham, England, showing 12 o'clock noon

The word noon is derived from Latin nona hora, the ninth hour of the day, and is related to the liturgical term none. The Roman and Western European medieval monastic day began at 6:00 a.m. (06:00) at the equinox by modern timekeeping, so the ninth hour started at what is now 3:00 p.m. (15:00) at the equinox. In English, the meaning of the word shifted to midday and the time gradually moved back to 12:00 local time (that is, not taking into account the modern invention of time zones). The change began in the 12th century and was fixed by the 14th century.[2]

Solar noon

Solar noon (informally high noon)[3] is the moment when the Sun contacts the observer's meridian, reaching its highest position above the horizon on that day ("Sun transit time"). This is also the origin of the terms ante meridiem (a.m.) and post meridiem (p.m.), as noted below. The Sun is directly overhead at solar noon at the Equator on the equinoxes, at the Tropic of Cancer (latitude 23°26′12.4″ N) on the June solstice and at the Tropic of Capricorn (23°26′12.4″ S) on the December solstice. In the Northern Hemisphere, north of the Tropic of Cancer, the Sun is due south of the observer at solar noon; in the Southern Hemisphere, south of the Tropic of Capricorn, it is due north.

The elapsed time from the local solar noon of one day to the next is exactly 24 hours on only four instances in any given year. This occurs when the effects of Earth’s obliquity of ecliptic and its orbital speed around the Sun offset each other. These four days for the current epoch are centered on 11 February, 13 May, 25 July, and 3 November.

It occurs at only one particular line of longitude each event. This line varies year to year, since Earth's true year is not an integer number of days. This event time and location also varies due to Earth's orbit being gravitationally perturbed by the planets.

These four 24-hour days occur in both hemispheres simultaneously. The precise UTC times for these four days also mark when the opposite line of longitude, 180° away, experiences precisely 24 hours from local midnight to local midnight the next day. Thus, four varying great circles of longitude define from year to year when a 24-hour day (noon to noon or midnight to midnight) occurs.

The two longest time spans from noon to noon occur twice each year, around 20 June (24 hours plus 13 seconds) and 21 December (24 hours plus 30 seconds).

The shortest time spans occur twice each year, around 25 March (24 hours minus 18 seconds) and 13 September (24 hours minus 22 seconds).


In the US, noon is commonly indicated by 12 p.m., and midnight by 12 a.m. While some argue that such usage is "improper"[4] based on the Latin meaning (a.m. stands for ante meridiem and p.m. for post meridiem, meaning "before midday" and "after midday" respectively), digital clocks are unable to display anything else, and an arbitrary decision must be made.

An earlier standard of indicating noon as "12M" or "12m" (for "meridies"), which was specified in the U.S. GPO Government Style Manual,[5] has fallen into relative obscurity; the current edition of the GPO makes no mention of it.[6][7][nb 1]

However, due to the lack of an international standard, the use of 12 a.m. and 12 p.m. can be confusing. Common alternative methods of representing these times are:

  • to use a 24-hour clock (00:00 and 12:00, 24:00; but never 24:01)
  • to use "12 noon" or "12 midnight" (though "12 midnight" may still present ambiguity regarding the specific date)
  • to specify midnight as between two successive days or dates (as in "midnight Saturday/Sunday" or "midnight December 14/15")
  • to avoid those specific times and to use "11:59 p.m." or "12:01 a.m." instead. (This is common in the travel industry to avoid confusion to passengers' schedules, especially train and plane schedules.)

See also


  1. ^ The 29th edition of the U.S. GPO Government Printing Office Style Manual (2000) section 12.9


  1. ^ "The Sun as an Energy Resource".
  2. ^ Online Etymology Dictionary
  3. ^ "high noon". The Cambridge Advanced Learner's Dictionary & Thesaurus. Cambridge University Press. Retrieved 2016-12-19.
  4. ^ Physics Laboratory FAQ "Times of Day"
  5. ^ Style manual of the Government Printing Office / (Rev. ed.). Washington, D.C. :. 1923.
  6. ^ "U.S. GPO Government Printing Office Style Manual Chapter 9". 2008. Retrieved 2009-06-11.
  7. ^ "U.S. GPO Government Printing Office Style Manual Chapter 12". 2008. Retrieved 2009-06-11.

External links

12-hour clock

The 12-hour clock is a time convention in which the 24 hours of the day are divided into two periods: a.m. (from Latin ante meridiem, translates to, before midday) and p.m. (from Latin post meridiem translates to, past midday). Each period consists of 12 hours numbered: 12 (acting as zero), 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11. The 24 hour/day cycle starts at 12 midnight (may be indicated as 12 a.m.), runs through 12 noon (may be indicated as 12 p.m.), and continues to the midnight at the end of the day. The 12-hour clock has been developed from the middle of the second millennium BC to the 16th century AD.

The 12-hour time convention is common in several English-speaking nations and former British colonies, as well as a few other countries.


The Angelus (; Latin for "angel") is a Catholic devotion commemorating the Incarnation. As with many Catholic prayers, the name Angelus is derived from its incipit—the first few words of the text: Angelus Domini nuntiavit Mariæ ("The Angel of the Lord declared unto Mary"). The devotion is practised by reciting as versicle and response three Biblical verses narrating the mystery, alternating with the prayer "Hail Mary". The Angelus exemplifies a species of prayers called the "prayer of the devotee".The devotion was traditionally recited in Roman Catholic churches, convents, and monasteries three times daily: 6:00 am, noon, and 6:00 pm (many churches still follow the devotion, and some practice it at home). The devotion is also used by some Anglican and Lutheran churches.

The Angelus is usually accompanied by the ringing of the Angelus bell, which is a call to prayer and to spread goodwill to everyone. The angel referred to in the prayer is Gabriel, a messenger of God who revealed to Mary that she would conceive a child to be born the Son of God (Luke 1:26–38).

Arctic Circle

The Arctic Circle is one of the two polar circles and the most northerly of the five major circles of latitude as shown on maps of Earth. It marks the northernmost point at which the centre of the noon sun is just visible on the December solstice and the southernmost point at which the centre of the midnight sun is just visible on the June solstice. The region north of this circle is known as the Arctic, and the zone just to the south is called the Northern Temperate Zone.

As seen from the Arctic, the Sun is above the horizon for 24 continuous hours at least once per year (and therefore visible at midnight) and below the horizon for 24 continuous hours at least once per year (and therefore not visible at noon). This is also true in the Antarctic region, south of the equivalent Antarctic Circle.

The position of the Arctic Circle is not fixed; as of 22 April 2019, it runs 66°33′47.6″ north of the Equator. Its latitude depends on the Earth's axial tilt, which fluctuates within a margin of more than 2° over a 41,000-year period, due to tidal forces resulting from the orbit of the Moon. Consequently, the Arctic Circle is currently drifting northwards at a speed of about 15 m (49 ft) per year.

Channel 4 News

Channel 4 News is the main news programme on British television broadcaster Channel 4. It is produced by ITN, and has been in operation since Channel 4's launch in November 1982.

Darkness at Noon

Darkness at Noon (German: Sonnenfinsternis) is a novel by Hungarian-born British novelist Arthur Koestler, first published in 1940. His best known work, it is the tale of Rubashov, an Old Bolshevik who is arrested, imprisoned, and tried for treason against the government that he had helped to create.

The novel is set in 1939 during the Stalinist Great Purge and Moscow show trials. Despite being based on real events, the novel does not name either Russia or the USSR, and tends to use generic terms to describe people and organizations: for example the Soviet government is referred to as "the Party" and Nazi Germany is referred to as "the Dictatorship". Joseph Stalin is represented by "Number One", a menacing dictator. The novel expresses the author's disillusionment with the Soviet Union's version of Communism at the outset of World War II.

In 1998, the Modern Library ranked Darkness at Noon number eight on its list of the 100 best English-language novels of the 20th century.


Dinner usually refers to the most significant meal of the day, which can be at noon or in the evening. However, the term "dinner" can have different meanings depending on culture, as it may mean a meal of any size eaten at any time of day. Historically, it referred to the first meal of the day eaten around noon, and is still sometimes used for a noon-time meal, particularly if it is a large or main meal. In many parts of the Western world, dinner is taken as the evening meal.

Greenwich Mean Time

Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London, reckoned from midnight. At different times in the past, it has been calculated in different ways, including being calculated from noon; as a consequence, it cannot be used to specify a precise time unless a context is given.

English speakers often use GMT as a synonym for Coordinated Universal Time (UTC). For navigation, it is considered equivalent to UT1 (the modern form of mean solar time at 0° longitude); but this meaning can differ from UTC by up to 0.9 s. The term GMT should not thus be used for technical purposes.Because of Earth's uneven speed in its elliptical orbit and its axial tilt, noon (12:00:00) GMT is rarely the exact moment the sun crosses the Greenwich meridian and reaches its highest point in the sky there. This event may occur up to 16 minutes before or after noon GMT, a discrepancy calculated by the equation of time. Noon GMT is the annual average (i.e. "mean") moment of this event, which accounts for the word "mean" in "Greenwich Mean Time".

Originally, astronomers considered a GMT day to start at noon, while for almost everyone else it started at midnight. To avoid confusion, the name Universal Time was introduced to denote GMT as counted from midnight. Astronomers preferred the old convention to simplify their observational data, so that each night was logged under a single calendar date. Today Universal Time usually refers to UTC or UT1.The term "GMT" is especially used by bodies connected with the United Kingdom, such as the BBC World Service, the Royal Navy, the Met Office and others particularly in Arab countries, such as the Middle East Broadcasting Centre and OSN. It is a term commonly used in the United Kingdom and countries of the Commonwealth, including Australia, New Zealand, South Africa, India, Pakistan, Bangladesh and Malaysia; and in many other countries of the Eastern Hemisphere.

High Noon

High Noon is a 1952 American Western film produced by Stanley Kramer from a screenplay by Carl Foreman, directed by Fred Zinnemann, and starring Gary Cooper. The plot, depicted in real time, centres on a town marshal who is torn between his sense of duty and love for his new bride and who must face a gang of killers alone.

Though mired in controversy with political overtones at the time of its release, the film was nominated for seven Academy Awards and won four (Actor, Editing, Music-Score, and Music-Song) as well as four Golden Globe Awards (Actor, Supporting Actress, Score, and Cinematography-Black and White). The award-winning score was written by Russian-born composer Dimitri Tiomkin.

High Noon was selected for preservation in the United States National Film Registry by the Library of Congress as "culturally, historically, or aesthetically significant" in 1989, the NFR's first year of existence. An iconic film whose story has been partly or completely repeated in later film productions, the ending scenes especially inspired a next-to-endless number of later films, including but not just limited to westerns.

High Noon Toons

High Noon Toons was a 3-hour programming block of cartoons hosted by two cowboy hand puppets named Haas and Lil' Jo (a Bonanza pun) shown on Cartoon Network in the mid-1990s. The series was made by Matt Thompson and Adam Reed, who later went on to create adult-themed cartoon series such as Sealab 2021 and Frisky Dingo for Adult Swim and Archer for FX.

Often the show had special themes, such as "Quick Draw McGraw: Pure Mustang". Haas and Lil' Jo also hosted Cartoon Network's "Spring Break '95", with the two on a beach setting with bikini-clad Barbie dolls, and which showed Spring Break-related cartoons. They also hosted the Thanksgiving Cartoon Parade in 1995.


An hour (symbol: h; also abbreviated hr.) is a unit of time conventionally reckoned as ​1⁄24 of a day and scientifically reckoned as 3,599–3,601 seconds, depending on conditions.

The hour was initially established in the ancient Near East as a variable measure of ​1⁄12 of the night or daytime. Such seasonal, temporal, or unequal hours varied by season and latitude. The hour was subsequently divided into 60 minutes, each of 60 seconds. Equal or equinoctial hours were taken as ​1⁄24 of the day as measured from noon to noon; the minor seasonal variations of this unit were eventually smoothed by making it ​1⁄24 of the mean solar day. Since this unit was not constant due to long term variations in the Earth's rotation, the hour was finally separated from the Earth's rotation and defined in terms of the atomic or physical second.

In the modern metric system, hours are an accepted unit of time defined as 3,600 atomic seconds. However, on rare occasions an hour may incorporate a positive or negative leap second, making it last 3,599 or 3,601 seconds, in order to keep it within 0.9 seconds of UT1, which is based on measurements of the mean solar day.

Julian day

Julian day is the continuous count of days since the beginning of the Julian Period and is used primarily by astronomers, and in software for easily calculating elapsed days between two events (e.g. food production date and sell by date).

The Julian Day Number (JDN) is the integer assigned to a whole solar day in the Julian day count starting from noon Universal time, with Julian day number 0 assigned to the day starting at noon on Monday, January 1, 4713 BC, proleptic Julian calendar (November 24, 4714 BC, in the proleptic Gregorian calendar), a date at which three multi-year cycles started (which are: Indiction, Solar, and Lunar cycles) and which preceded any dates in recorded history. For example, the Julian day number for the day starting at 12:00 UT on January 1, 2000, was 2 451 545.The Julian date (JD) of any instant is the Julian day number plus the fraction of a day since the preceding noon in Universal Time. Julian dates are expressed as a Julian day number with a decimal fraction added. For example, the Julian Date for 00:30:00.0 UT January 1, 2013, is 2 456 293.520 833.The Julian Period is a chronological interval of 7980 years; year 1 of the Julian Period was 4713 BC. It has been used by historians since its introduction in 1583 to convert between different calendars. The Julian calendar year 2019 is year 6732 of the current Julian Period. The next Julian Period begins in the year AD 3268.


Lunch, the abbreviation for luncheon, is a meal eaten around midday. During the 20th century, the meaning gradually narrowed to a small or mid-sized meal eaten midday. Lunch is commonly the second meal of the day, after breakfast. The meal varies in size depending on the culture, and significant variations exist in different areas of the world.


Midnight is the transition time from one day to the next – the moment when the date changes. In ancient Roman timekeeping, midnight was halfway between sunset and sunrise (i.e., solar midnight), varying according to the seasons. By clock time, midnight is the opposite of noon, differing from it by 12 hours.

Solar midnight is the time opposite to solar noon, when the Sun is closest to the nadir, and the night is equidistant from dusk and dawn. Due to the advent of time zones, which regularize time across a range of meridians, and daylight saving time, it rarely coincides with 12 midnight on the clock. Solar midnight depends on longitude and time of the year rather than on time zone.

In the Northern Hemisphere, "midnight" had an ancient geographic association with "north" (as did "noon" with "south" – see noon). Modern Polish, Belarusian, Ukrainian and Serbian preserve this association with its word for "midnight" (północ, поўнач, північ, пoнoħ – literally "half-night"), which also means "north".

Noon chai

Noon chai, also called sheer chai (from Persian, meaning 'milk tea'), gulabi chai, Kashmiri tea or pink tea, is a traditional tea beverage, originating from the Indian subcontinent, most probably from the Kashmir Valley, made with gunpowder tea, milk and baking soda.

South African Standard Time

South African Standard Time (SAST) is the time zone used by all of South Africa, Botswana as well as Eswatini and Lesotho. The zone is two hours ahead of UTC (UTC+02:00) and is the same as Central Africa Time. Daylight saving time is not observed in either time zone. Solar noon in this time zone occurs at 30° E in SAST, effectively making Pietermaritzburg at the correct solar noon point, with Johannesburg and Pretoria slightly west at 28° E and Durban slightly east at 31° E. Thus, most of South Africa's population experience true solar noon at approximately 12:00 daily.

The western Northern Cape and Western Cape differ, however. Everywhere on land west of 22°30′ E effectively experiences year-round daylight saving time because of its location in true UTC+01:00 but still being in South African Standard Time. Sunrise and sunset are thus relatively late in Cape Town, compared to the rest of the country.

To illustrate, daylight hours for South Africa's western and eastern-most major cities:

The South African National Time Standard, or 'SA Time' Master Clock, is maintained at the Time and Frequency Laboratory of the National Metrology Institute of South Africa (NMISA) at Pretoria and is distributed publicly by an NTP Internet Time service.

Sun-synchronous orbit

A Sun-synchronous orbit (SSO, also called a heliosynchronous orbit) is a nearly polar orbit around a planet, in which the satellite passes over any given point of the planet's surface at the same local mean solar time. More technically, it is an orbit arranged so that it precesses through one complete revolution each year, so it always maintains the same relationship with the Sun.

Tea (meal)

Tea (in reference to food, rather than the drink) has long been used as an umbrella term for several different meals. Isabella Beeton, whose books on home economics were widely read in the 19th century, describes afternoon teas of various kinds, and provides menus for the old-fashioned tea, the at-home tea, the family tea, and the high tea. Teatime is the time at which the tea meal is usually eaten, which is late afternoon to early evening, being the equivalent of merienda. Tea as a meal is associated with Great Britain, Ireland, and some Commonwealth countries.

The Ballad of High Noon

“The Ballad of High Noon” (or “Do Not Forsake Me, O My Darlin’”) is a popular song published in 1952, with music by Dimitri Tiomkin and lyrics by Ned Washington.

Zuhr prayer

The Zuhr prayer (Arabic: صلاة الظهر‎, ṣalāt aẓ-ẓuhr IPA: [sˤalaːt aðˤðˤuhr], "noon prayer"; also transliterated Duhr, Dhuhr or Duhur) is the second of the five daily prayers (salat) performed daily by practicing Muslims. It is also known as ‘the middle prayer’ (ṣalāt al-wusṭā)The Islamic day begins at Fajr which is the first prayer. The five daily prayers collectively are one of the Five Pillars of Islam in Sunni Islam, and one of the ten Practices of the Religion (فروع الدين furūʿ ad-dīn) according to Shia Islam.

On Friday the Zuhr prayer is replaced by Jumu'ah, which is obligatory for Muslim men who are above the age of puberty to pray in congregation either in the mosque of the city they live in or with a group of Muslims. Women are recommended to also do so at home, but not obligated. The Zuhr prayer is led by a sermon given by the leader of the mosque to educate, bond, guide, and improve the quality of the community as well as propagate Islam.

Parts of a day

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