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Day

Index Day

A day is the time period of a full rotation of the Earth with respect to the Sun. [1]

Table of Contents

  1. 143 relations: Afternoon, Agnes of Rome, American English, Ancient Egypt, Ancient Rome, Astronomical object, Astronomy, Atmosphere of Earth, Atom, Book of Genesis, Caesium, Calendar, Calendar date, Cambrian, Cambridge Advanced Learner's Dictionary, Carboniferous, Celestial equator, Celestial sphere, Ceres (dwarf planet), Christmas Eve, Chronometry, Circadian rhythm, Collins English Dictionary, Computer, Coordinated Universal Time, Cretaceous, Culmination, Danish language, Darkness, Dawn, Day length fluctuations, Daylight saving time, Daytime, Decimal time, Determination of the day of the week, Devonian, Diurnality, Dusk, Dutch language, Earth, Earth's rotation, Encyclopædia Britannica, Energy level, English language in England, Evening, Florentine calendar, Fossil, Friday, German language, Gravity, ... Expand index (93 more) »

  2. Orders of magnitude (time)

Afternoon

Afternoon is the time between noon and sunset or evening.

See Day and Afternoon

Agnes of Rome

Agnes of Rome is a virgin martyr, venerated as a saint in the Catholic Church, Oriental Orthodox Church and the Eastern Orthodox Church, as well as the Anglican Communion and Lutheran Churches.

See Day and Agnes of Rome

American English

American English (AmE), sometimes called United States English or U.S. English, is the set of varieties of the English language native to the United States.

See Day and American English

Ancient Egypt

Ancient Egypt was a civilization of ancient Northeast Africa.

See Day and Ancient Egypt

Ancient Rome

In modern historiography, ancient Rome is the Roman civilisation from the founding of the Italian city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD.

See Day and Ancient Rome

Astronomical object

An astronomical object, celestial object, stellar object or heavenly body is a naturally occurring physical entity, association, or structure that exists within the observable universe.

See Day and Astronomical object

Astronomy

Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos.

See Day and Astronomy

Atmosphere of Earth

The atmosphere of Earth is composed of a layer of gas mixture that surrounds the Earth's planetary surface (both lands and oceans), known collectively as air, with variable quantities of suspended aerosols and particulates (which create weather features such as clouds and hazes), all retained by Earth's gravity.

See Day and Atmosphere of Earth

Atom

Atoms are the basic particles of the chemical elements.

See Day and Atom

Book of Genesis

The Book of Genesis (from Greek; בְּרֵאשִׁית|Bərēʾšīṯ|In beginning; Liber Genesis) is the first book of the Hebrew Bible and the Christian Old Testament.

See Day and Book of Genesis

Caesium

Caesium (IUPAC spelling; cesium in American English) is a chemical element; it has symbol Cs and atomic number 55.

See Day and Caesium

Calendar

A calendar is a system of organizing days. Day and calendar are units of time.

See Day and Calendar

Calendar date

A calendar date is a reference to a particular day represented within a calendar system.

See Day and Calendar date

Cambrian

The Cambrian is the first geological period of the Paleozoic Era, and the Phanerozoic Eon.

See Day and Cambrian

Cambridge Advanced Learner's Dictionary

The Cambridge Advanced Learner's Dictionary (abbreviated CALD) is a British dictionary of the English language.

See Day and Cambridge Advanced Learner's Dictionary

Carboniferous

The Carboniferous is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period Ma (million years ago) to the beginning of the Permian Period, Ma.

See Day and Carboniferous

Celestial equator

The celestial equator is the great circle of the imaginary celestial sphere on the same plane as the equator of Earth.

See Day and Celestial equator

Celestial sphere

In astronomy and navigation, the celestial sphere is an abstract sphere that has an arbitrarily large radius and is concentric to Earth.

See Day and Celestial sphere

Ceres (dwarf planet)

Ceres (minor-planet designation: 1 Ceres) is a dwarf planet in the middle main asteroid belt between the orbits of Mars and Jupiter.

See Day and Ceres (dwarf planet)

Christmas Eve

Christmas Eve is the evening or entire day before Christmas Day, the festival commemorating the birth of Jesus.

See Day and Christmas Eve

Chronometry

Chronometry or horology is the science studying the measurement of time and timekeeping. Chronometry enables the establishment of standard measurements of time, which have applications in a broad range of social and scientific areas. Horology usually refers specifically to the study of mechanical timekeeping devices, while chronometry is broader in scope, also including biological behaviours with respect to time (biochronometry), as well as the dating of geological material (geochronometry).

See Day and Chronometry

Circadian rhythm

A circadian rhythm, or circadian cycle, is a natural oscillation that repeats roughly every 24 hours.

See Day and Circadian rhythm

Collins English Dictionary

The Collins English Dictionary is a printed and online dictionary of English.

See Day and Collins English Dictionary

Computer

A computer is a machine that can be programmed to automatically carry out sequences of arithmetic or logical operations (computation).

See Day and Computer

Coordinated Universal Time

Coordinated Universal Time (UTC) is the primary time standard globally used to regulate clocks and time.

See Day and Coordinated Universal Time

Cretaceous

The Cretaceous is a geological period that lasted from about 145 to 66 million years ago (Mya).

See Day and Cretaceous

Culmination

In observational astronomy, culmination is the passage of a celestial object (such as the Sun, the Moon, a planet, a star, constellation or a deep-sky object) across the observer's local meridian.

See Day and Culmination

Danish language

Danish (dansk, dansk sprog) is a North Germanic language from the Indo-European language family spoken by about six million people, principally in and around Denmark.

See Day and Danish language

Darkness

Darkness is defined as a lack of illumination, an absence of visible light, or a surface that absorbs light.

See Day and Darkness

Dawn

Dawn is the time that marks the beginning of twilight before sunrise.

See Day and Dawn

Day length fluctuations

The length of the day (LOD), which has increased over the long term of Earth's history due to tidal effects, is also subject to fluctuations on a shorter scale of time.

See Day and Day length fluctuations

Daylight saving time

Daylight saving time (DST), also referred to as daylight saving(s), daylight savings time, daylight time (United States and Canada), or summer time (United Kingdom, European Union, and others), is the practice of advancing clocks to make better use of the longer daylight available during summer so that darkness falls at a later clock time.

See Day and Daylight saving time

Daytime

Daytime as observed on Earth is the period of the day during which a given location experiences natural illumination from direct sunlight.

See Day and Daytime

Decimal time

Decimal time is the representation of the time of day using units which are decimally related. Day and decimal time are units of time.

See Day and Decimal time

Determination of the day of the week

The determination of the day of the week for any date may be performed with a variety of algorithms.

See Day and Determination of the day of the week

Devonian

The Devonian is a geologic period and system of the Paleozoic era during the Phanerozoic eon, spanning 60.3 million years from the end of the preceding Silurian period at million years ago (Ma), to the beginning of the succeeding Carboniferous period at Ma.

See Day and Devonian

Diurnality

Diurnality is a form of plant and animal behavior characterized by activity during daytime, with a period of sleeping or other inactivity at night.

See Day and Diurnality

Dusk

Dusk occurs at the darkest stage of twilight, or at the very end of astronomical twilight after sunset and just before nightfall.

See Day and Dusk

Dutch language

Dutch (Nederlands.) is a West Germanic language, spoken by about 25 million people as a first language and 5 million as a second language and is the third most spoken Germanic language.

See Day and Dutch language

Earth

Earth is the third planet from the Sun and the only astronomical object known to harbor life.

See Day and Earth

Earth's rotation

Earth's rotation or Earth's spin is the rotation of planet Earth around its own axis, as well as changes in the orientation of the rotation axis in space.

See Day and Earth's rotation

Encyclopædia Britannica

The British Encyclopaedia is a general knowledge English-language encyclopaedia.

See Day and Encyclopædia Britannica

Energy level

A quantum mechanical system or particle that is bound—that is, confined spatially—can only take on certain discrete values of energy, called energy levels.

See Day and Energy level

English language in England

The English language spoken and written in England encompasses a diverse range of accents and dialects.

See Day and English language in England

Evening

Evening is the period of a day that begins at the end of daylight and overlaps with the beginning of night.

See Day and Evening

Florentine calendar

The Florentine calendar, also referred to as the stylus Florentinus ("Florentine style"), was the calendar used in the Republic of Florence in Italy during the Middle Ages.

See Day and Florentine calendar

Fossil

A fossil (from Classical Latin) is any preserved remains, impression, or trace of any once-living thing from a past geological age.

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Friday

Friday is the day of the week between Thursday and Saturday.

See Day and Friday

German language

German (Standard High German: Deutsch) is a West Germanic language in the Indo-European language family, mainly spoken in Western and Central Europe. It is the most widely spoken and official or co-official language in Germany, Austria, Switzerland, Liechtenstein, and the Italian province of South Tyrol.

See Day and German language

Gravity

In physics, gravity is a fundamental interaction which causes mutual attraction between all things that have mass.

See Day and Gravity

Halloween

Halloween or Hallowe'en (less commonly known as Allhalloween, All Hallows' Eve, or All Saints' Eve) is a celebration observed in many countries on 31 October, the eve of the Western Christian feast of All Hallows' Day.

See Day and Halloween

Hebrew Bible

The Hebrew Bible or Tanakh (. Random House Webster's Unabridged Dictionary. Hebrew), also known in Hebrew as Miqra (Hebrew), is the canonical collection of Hebrew scriptures, comprising the Torah, the Nevi'im, and the Ketuvim.

See Day and Hebrew Bible

Hebrew calendar

The Hebrew calendar (translit), also called the Jewish calendar, is a lunisolar calendar used today for Jewish religious observance and as an official calendar of Israel.

See Day and Hebrew calendar

History of China

The history of China spans several millennia across a wide geographical area.

See Day and History of China

Holiday

A holiday is a day or other period of time set aside for festivals or recreation.

See Day and Holiday

Horizon

The horizon is the apparent curve that separates the surface of a celestial body from its sky when viewed from the perspective of an observer on or near the surface of the relevant body.

See Day and Horizon

Hour

An hour (symbol: h; also abbreviated hr) is a unit of time historically reckoned as of a day and defined contemporarily as exactly 3,600 seconds (SI). Day and hour are Orders of magnitude (time) and units of time.

See Day and Hour

Hyperfine structure

In atomic physics, hyperfine structure is defined by small shifts in otherwise degenerate electronic energy levels and the resulting splittings in those electronic energy levels of atoms, molecules, and ions, due to electromagnetic multipole interaction between the nucleus and electron clouds.

See Day and Hyperfine structure

Icelandic language

Icelandic (íslenska) is a North Germanic language from the Indo-European language family spoken by about 314,000 people, the vast majority of whom live in Iceland, where it is the national language.

See Day and Icelandic language

International Bureau of Weights and Measures

The International Bureau of Weights and Measures (Bureau international des poids et mesures, BIPM) is an intergovernmental organisation, through which its 59 member-states act on measurement standards in areas including chemistry, ionising radiation, physical metrology, as well as the International System of Units (SI) and Coordinated Universal Time (UTC).

See Day and International Bureau of Weights and Measures

International Earth Rotation and Reference Systems Service

The International Earth Rotation and Reference Systems Service (IERS), formerly the International Earth Rotation Service, is the body responsible for maintaining global time and reference frame standards, notably through its Earth Orientation Parameter (EOP) and International Celestial Reference System (ICRS) groups.

See Day and International Earth Rotation and Reference Systems Service

International System of Units

The International System of Units, internationally known by the abbreviation SI (from French Système international d'unités), is the modern form of the metric system and the world's most widely used system of measurement.

See Day and International System of Units

ISO 8601

ISO 8601 is an international standard covering the worldwide exchange and communication of date and time-related data.

See Day and ISO 8601

ISO week date

The ISO week date system is effectively a leap week calendar system that is part of the ISO 8601 date and time standard issued by the International Organization for Standardization (ISO) since 1988 (last revised in 2019) and, before that, it was defined in ISO (R) 2015 since 1971.

See Day and ISO week date

John W. Wells

John West Wells (July 15, 1907 – January 12, 1994) was an American paleontologist, biologist and geologist who focused his research on corals.

See Day and John W. Wells

Judaism

Judaism (יַהֲדוּת|translit.

See Day and Judaism

Jupiter

Jupiter is the fifth planet from the Sun and the largest in the Solar System.

See Day and Jupiter

Leap second

A leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time (UTC), to accommodate the difference between precise time (International Atomic Time (TAI), as measured by atomic clocks) and imprecise observed solar time (UT1), which varies due to irregularities and long-term slowdown in the Earth's rotation.

See Day and Leap second

Life

Life is a quality that distinguishes matter that has biological processes, such as signaling and self-sustaining processes, from matter that does not.

See Day and Life

Light pollution

Light pollution is the presence of any unwanted, inappropriate, or excessive artificial lighting.

See Day and Light pollution

Local mean time

Local mean time (LMT) is a form of solar time that corrects the variations of local apparent time, forming a uniform time scale at a specific longitude.

See Day and Local mean time

Longitude

Longitude is a geographic coordinate that specifies the east–west position of a point on the surface of the Earth, or another celestial body.

See Day and Longitude

Lunar calendar

A lunar calendar is a calendar based on the monthly cycles of the Moon's phases (synodic months, lunations), in contrast to solar calendars, whose annual cycles are based on the solar year.

See Day and Lunar calendar

Lunar phase

A lunar phase or Moon phase is the apparent shape of the Moon's directly sunlit portion as viewed from the Earth (because the Moon is tidally locked with the Earth, the same hemisphere is always facing the Earth).

See Day and Lunar phase

Magnitude (astronomy)

In astronomy, magnitude is measure of the brightness of an object, usually in a defined passband.

See Day and Magnitude (astronomy)

Man-hour

A man-hour or human-hour is the amount of work performed by the average worker in one hour.

See Day and Man-hour

Mars

Mars is the fourth planet from the Sun.

See Day and Mars

Mercury (planet)

Mercury is the first planet from the Sun and the smallest in the Solar System.

See Day and Mercury (planet)

Meridian (geography)

In geography and geodesy, a meridian is the locus connecting points of equal longitude, which is the angle (in degrees or other units) east or west of a given prime meridian (currently, the IERS Reference Meridian).

See Day and Meridian (geography)

Metric time

Metric time is the measure of time intervals using the metric system.

See Day and Metric time

Middle Ages

In the history of Europe, the Middle Ages or medieval period (also spelt mediaeval or mediæval) lasted from approximately 500 to 1500 AD.

See Day and Middle Ages

Midnight

Midnight is the transition time from one day to the next – the moment when the date changes, on the local official clock time for any particular jurisdiction.

See Day and Midnight

Midtown Manhattan

Midtown Manhattan is the central portion of the New York City borough of Manhattan and serves as the city's primary central business district.

See Day and Midtown Manhattan

Millisecond

A millisecond (from milli- and second; symbol: ms) is a unit of time in the International System of Units equal to one thousandth (0.001 or 10−3 or 1/1000) of a second or 1000 microseconds. Day and millisecond are Orders of magnitude (time).

See Day and Millisecond

Minute and second of arc

A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol, is a unit of angular measurement equal to of one degree.

See Day and Minute and second of arc

Month

A month is a unit of time, used with calendars, that is approximately as long as a natural orbital period of the Moon; the words month and Moon are cognates. Day and month are Orders of magnitude (time) and units of time.

See Day and Month

Moon

The Moon is Earth's only natural satellite.

See Day and Moon

Morning

Morning is the period from sunrise to noon.

See Day and Morning

NASA

The National Aeronautics and Space Administration (NASA) is an independent agency of the U.S. federal government responsible for the civil space program, aeronautics research, and space research.

See Day and NASA

National Academy of Sciences

The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization.

See Day and National Academy of Sciences

Neptune

Neptune is the eighth and farthest known planet from the Sun.

See Day and Neptune

Night

Night or nighttime is the period of darkness when the Sun is below the horizon.

See Day and Night

Non-SI units mentioned in the SI

While the International System of Units (SI) is used throughout the world in all fields, many non-SI units continue to be used in the scientific, technical, and commercial literature.

See Day and Non-SI units mentioned in the SI

Noon

Noon (or midday) is 12 o'clock in the daytime.

See Day and Noon

Nychthemeron

Nychthemeron, occasionally nycthemeron or nuchthemeron, is a period of 24 consecutive hours. Day and Nychthemeron are units of time.

See Day and Nychthemeron

Old English

Old English (Englisċ or Ænglisc), or Anglo-Saxon, was the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages.

See Day and Old English

Ordinal date

An ordinal date is a calendar date typically consisting of a year and an ordinal number, ranging between 1 and 366 (starting on January 1), representing the multiples of a day, called day of the year or ordinal day number (also known as ordinal day or day number).

See Day and Ordinal date

Pluto

Pluto (minor-planet designation: 134340 Pluto) is a dwarf planet in the Kuiper belt, a ring of bodies beyond the orbit of Neptune.

See Day and Pluto

Productivity

Productivity is the efficiency of production of goods or services expressed by some measure.

See Day and Productivity

Proto-Germanic language

Proto-Germanic (abbreviated PGmc; also called Common Germanic) is the reconstructed proto-language of the Germanic branch of the Indo-European languages.

See Day and Proto-Germanic language

Radioactive decay

Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation.

See Day and Radioactive decay

Rail transport

Rail transport (also known as train transport) is a means of transport using wheeled vehicles running in tracks, which usually consist of two parallel steel rails.

See Day and Rail transport

Refraction

In physics, refraction is the redirection of a wave as it passes from one medium to another.

See Day and Refraction

Rotation

Rotation or rotational motion is the circular movement of an object around a central line, known as axis of rotation.

See Day and Rotation

Rotation period (astronomy)

In astronomy, the rotation period or spin period of a celestial object (e.g., star, planet, moon, asteroid) has two definitions.

See Day and Rotation period (astronomy)

Saturn

Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter.

See Day and Saturn

Season

A season is a division of the year based on changes in weather, ecology, and the number of daylight hours in a given region. Day and season are units of time.

See Day and Season

Second

The second (symbol: s) is the unit of time in the International System of Units (SI), historically defined as of a day – this factor derived from the division of the day first into 24 hours, then to 60 minutes and finally to 60 seconds each (24 × 60 × 60. Day and second are Orders of magnitude (time) and units of time.

See Day and Second

Sidereal time

Sidereal time ("sidereal" pronounced) is a system of timekeeping used especially by astronomers. Day and Sidereal time are units of time.

See Day and Sidereal time

Solar calendar

A solar calendar is a calendar whose dates indicate the season or almost equivalently the apparent position of the Sun relative to the stars.

See Day and Solar calendar

Solar System

The Solar SystemCapitalization of the name varies.

See Day and Solar System

Space.com

Space.com is an online publication focused on space exploration, astronomy, skywatching and entertainment, with editorial teams based in the United States and United Kingdom.

See Day and Space.com

Springer Science+Business Media

Springer Science+Business Media, commonly known as Springer, is a German multinational publishing company of books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing.

See Day and Springer Science+Business Media

Standard time

Standard time is the synchronization of clocks within a geographical region to a single time standard, rather than a local mean time standard.

See Day and Standard time

Stationary state

A stationary state is a quantum state with all observables independent of time.

See Day and Stationary state

Sun

The Sun is the star at the center of the Solar System.

See Day and Sun

Sundial

A sundial is a horological device that tells the time of day (referred to as civil time in modern usage) when direct sunlight shines by the apparent position of the Sun in the sky.

See Day and Sundial

Sunlight

Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light.

See Day and Sunlight

Sunrise

Sunrise (or sunup) is the moment when the upper rim of the Sun appears on the horizon in the morning.

See Day and Sunrise

Sunset

Sunset (or sundown) is the disappearance of the Sun below the horizon of the Earth (or any other astronomical object in the Solar System) due to its rotation.

See Day and Sunset

Swedish language

Swedish (svenska) is a North Germanic language from the Indo-European language family, spoken predominantly in Sweden and in parts of Finland.

See Day and Swedish language

Synodic day

A synodic day (or synodic rotation period or solar day) is the period for a celestial object to rotate once in relation to the star it is orbiting, and is the basis of solar time. Day and synodic day are units of time.

See Day and Synodic day

The Verge

The Verge is an American technology news website headquartered in Lower Manhattan, New York City and operated by Vox Media.

See Day and The Verge

Thermoregulation

Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different.

See Day and Thermoregulation

Tidal acceleration

Tidal acceleration is an effect of the tidal forces between an orbiting natural satellite (e.g. the Moon) and the primary planet that it orbits (e.g. Earth).

See Day and Tidal acceleration

Time

Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, and into the future.

See Day and Time

Time zone

A time zone is an area which observes a uniform standard time for legal, commercial and social purposes.

See Day and Time zone

Traffic collision

A traffic collision, also known as a motor vehicle collision, or car crash, occurs when a vehicle collides with another vehicle, pedestrian, animal, road debris, or other moving or stationary obstruction, such as a tree, pole or building.

See Day and Traffic collision

Triassic

The Triassic (sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago (Mya), to the beginning of the Jurassic Period 201.4 Mya.

See Day and Triassic

Tropical year

A tropical year or solar year (or tropical period) is the time that the Sun takes to return to the same position in the sky – as viewed from the Earth or another celestial body of the Solar System – thus completing a full cycle of astronomical seasons. Day and tropical year are units of time.

See Day and Tropical year

Tropics

The tropics are the regions of Earth surrounding the Equator.

See Day and Tropics

Twilight

Twilight is light produced by sunlight scattering in the upper atmosphere, when the Sun is below the horizon, which illuminates the lower atmosphere and the Earth's surface.

See Day and Twilight

United States Naval Observatory

The United States Naval Observatory (USNO) is a scientific and military facility that produces geopositioning, navigation and timekeeping data for the United States Navy and the United States Department of Defense.

See Day and United States Naval Observatory

Universe

The universe is all of space and time and their contents.

See Day and Universe

Uranus

Uranus is the seventh planet from the Sun.

See Day and Uranus

UTC+00:00

UTC+00:00 is an identifier for a time offset from UTC of +00:00.

See Day and UTC+00:00

Venus

Venus is the second planet from the Sun.

See Day and Venus

Week

A week is a unit of time equal to seven days. Day and week are units of time.

See Day and Week

Workweek and weekend

The weekdays and weekend are the complementary parts of the week devoted to labour and rest, respectively.

See Day and Workweek and weekend

World Meteorological Day

World Meteorological Day was established in 1951 to commemorate the establishment of the World Meteorological Organization on 23 March 1950.

See Day and World Meteorological Day

Year

A year is the time taken for astronomical objects to complete one orbit.

See Day and Year

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, translating to "before midday") and p.m. (from Latin, translating to "after midday").

See Day and 12-hour clock

24-hour clock

The modern 24-hour clock is the convention of timekeeping in which the day runs from midnight to midnight and is divided into 24 hours.

See Day and 24-hour clock

See also

Orders of magnitude (time)

References

[1] https://en.wikipedia.org/wiki/Day

Also known as Civil day, Day duration, Day unit, Parts of a day, Parts of the day, SI day, SI days, Seconds in a day, .

, Halloween, Hebrew Bible, Hebrew calendar, History of China, Holiday, Horizon, Hour, Hyperfine structure, Icelandic language, International Bureau of Weights and Measures, International Earth Rotation and Reference Systems Service, International System of Units, ISO 8601, ISO week date, John W. Wells, Judaism, Jupiter, Leap second, Life, Light pollution, Local mean time, Longitude, Lunar calendar, Lunar phase, Magnitude (astronomy), Man-hour, Mars, Mercury (planet), Meridian (geography), Metric time, Middle Ages, Midnight, Midtown Manhattan, Millisecond, Minute and second of arc, Month, Moon, Morning, NASA, National Academy of Sciences, Neptune, Night, Non-SI units mentioned in the SI, Noon, Nychthemeron, Old English, Ordinal date, Pluto, Productivity, Proto-Germanic language, Radioactive decay, Rail transport, Refraction, Rotation, Rotation period (astronomy), Saturn, Season, Second, Sidereal time, Solar calendar, Solar System, Space.com, Springer Science+Business Media, Standard time, Stationary state, Sun, Sundial, Sunlight, Sunrise, Sunset, Swedish language, Synodic day, The Verge, Thermoregulation, Tidal acceleration, Time, Time zone, Traffic collision, Triassic, Tropical year, Tropics, Twilight, United States Naval Observatory, Universe, Uranus, UTC+00:00, Venus, Week, Workweek and weekend, World Meteorological Day, Year, 12-hour clock, 24-hour clock.