A composite image showing the terminator dividing night from day, running across Europe and Africa. Observers on the surface of the earth along this terminator will see a sunset.

Sunset, also called sundown in some American English dialects, is the time at which the Sun disappears below the horizon in the west. It should not be confused with dusk, which is the point at which darkness falls, some time after the beginning of twilight when the Sun itself sets. Sunclipse is the word collectively coined by Buckminster Fuller's family to replace the geocentric term sunset and better guide intuition, as the sun is not the body which is actually moving in a sunset. Download high resolution version (1024x1024, 143 KB) Wikipedia does not have an article with this exact name. ... Download high resolution version (1024x1024, 143 KB) Wikipedia does not have an article with this exact name. ... World map with terminator Photograph of part of the terminator crossing the surface of the Earth, as seen from the ISS. The terminator is diffuse and shows the gradual transition to darkness that is experienced as twilight on the surface. ... English language spread in the United States. ... A dialect (from the Greek word διάλεκτος, dialektos) is a variety of a language used by people from a particular geographic area. ... Horizon. ... Dusk in Breaux Bridge, Louisiana, USA. Dusk or civil dusk is the time at which the sun is 6 degrees below the horizon in the evening. ... It has been suggested that this article or section be merged with Dawn. ... Richard Buckminster (Bucky) Fuller (July 12[1], 1895 – July 1, 1983) was an American visionary, designer, architect, poet, author, and inventor. ...

Sun setting over Lake Päijänne at Sysmä, Finland

The red hues of the sky at sunset and sunrise are caused by Mie Scattering, not Rayleigh Scattering. The colours of the sky throughout the day and at sunrise and sunset, are explained by the phenomena of both Rayleigh Scattering and Mie Scattering. The colour of the sky described by Rayleigh Scattering applies to the hues of blue, violet and green, not to the reds, oranges, peaches and purples of sunrise and sunset. Rayleigh Scattering is scattering of shorter wavelength light (e.g. blue & violet) by air atoms and molecules (not statistical variations in density of the Earth's atmosphere). The magnitude or strength of Rayleigh Scattering varies by the reciprocal of the wavelength raised to the fourth power, and hence does not explain the beautiful variations of reds, purples, oranges and peachy colours. The latter colours arise from Mie Scattering, low angle scattering of light off dust, soot, smoke and (ash) particles. Mie Scattering (producing the colours of sunset and sunrise) is beautifully recognizable down-wind of and after dust storms, forest fires and volcanic eruptions that inject large quantities of fine particulate matter into the atmosphere. A number of eruptions in recent times, such as those of Mount Pinatubo in 1991 and Krakatoa in 1883, have been sufficiently large to produce remarkable sunsets and sunrises all over the world. Sometimes just before sunrise or after sunset a green flash can be seen. Image File history File linksMetadata Download high resolution version (2399x1599, 1295 KB) Source: Joonas Lyytinen File links The following pages link to this file: Finland Lake Päijänne Metadata This file contains additional information, probably added from the digital camera or scanner used to create or digitize it. ... Image File history File linksMetadata Download high resolution version (2399x1599, 1295 KB) Source: Joonas Lyytinen File links The following pages link to this file: Finland Lake Päijänne Metadata This file contains additional information, probably added from the digital camera or scanner used to create or digitize it. ... Lake Päijänne is the third biggest lake in Finland (1038 km2 water area). ... Sysmä is a municipality of Finland. ... The Rayleigh effect, seconds before sunrise in New Zealand Sunrise, also called sunup in some American English dialects, is the time at which the first part of the Sun appears above the horizon in the east. ... The Mie theory also called Lorenz-Mie theory is a complete mathematical-physical theory of the scattering of electromagnetic radiation by spherical particles, developed by Gustav Mie in 1908. ... Rayleigh scattering causing a reddened sky at sunset Rayleigh scattering (named after Lord Rayleigh) is the scattering of light, or other electromagnetic radiation, by particles much smaller than the wavelength of the light. ... Layers of Atmosphere (NOAA) Air redirects here. ... Smoke from a wildfire Smoke is a suspension in air (aerosol) of small particles resulting from incomplete combustion of a fuel. ... Diamond Head, a well-known backdrop to Waikiki in Hawaii, is an ash cone that solidified into tuff Volcanic ash is the term for very fine rock and mineral particles less than 2 mm in diameter that are ejected from a volcanic vent. ... This article is about volcanoes in geology. ... Mount Pinatubo is an active volcano located on the island of Luzon in the Philippines, at the intersection of the borders of the provinces of Zambales, Tarlac, and Pampanga. ... Krakatoa (Indonesian name: Krakatau, Portuguese name: Krakatao) is a volcanic island in the Sunda Strait between Java and Sumatra in Indonesia. ... Green flashes and green rays are rare optical phenomena that occur shortly after sunset or before sunrise, when a green spot is visible for a short period of time above the sun, or a green ray shoots up from the sunset point. ...

The sunset is often more brightly coloured than the sunrise, with the shades of red and orange being more vibrant. The atmosphere responds in a number of ways to exposure to the Sun during daylight hours. In particular, there tends to be more dust in the lower atmosphere at the end of the day than at the beginning. During the day, the Sun heats the surface of the Earth, lowering the relative humidity and increasing wind speed and turbulence, which serves to lift dust into the air. However, differences between sunrise and sunset may in some cases depend more on the geographical particulars of the location from which they are viewed. For example, on a west-facing coastline, sunset occurs over water while sunrise occurs over land. This article does not cite its references or sources. ... In fluid dynamics, turbulence or turbulent flow is a flow regime characterized by chaotic, stochastic property changes. ... Geography (from the Greek words Ge (γη) or Gaea (γαια), both meaning Earth, and graphein (γραφειν) meaning to describe or to writeor to map) is the study of the Earths features and of the distribution of life on the earth, including human life and the effects of human activity. ...

A Martian sunset taken by the Spirit Rover May 2005.

The timing of sunset varies with the time of year and the latitude of the location from which it is viewed. The timing can also vary in local time, with the location's precise longitude. Changes in timing of sunset are generally driven by the axial tilt of Earth and the planet's movement around its orbit, but some differences exist. For example, in the Northern Hemisphere, the earliest sunset is not at the winter solstice around December 21, but rather in early December. Likewise, the latest sunset is not at the summer solstice around June 21, but in early July. The same phenomenon exists in the Southern Hemisphere except with the dates swapped. For one or two weeks surrounding both solstices, both sunrise and sunset get slightly later each day. Even on the equator, sunrise and sunset shift several minutes back and forth through the year, along with solar noon. This effect is plotted by an analemma. Image File history File links Download high resolution version (2486x1914, 975 KB)Photograph of Martian sunset taken May 19th, 2005 by NASAs Mars Exploration Rover: Spirit at Gusev crater. ... Image File history File links Download high resolution version (2486x1914, 975 KB)Photograph of Martian sunset taken May 19th, 2005 by NASAs Mars Exploration Rover: Spirit at Gusev crater. ... The mission patch for Spirit, featuring Marvin the Martian. ... Latitude, usually denoted symbolically by the Greek letter φ, gives the location of a place on Earth north or south of the Equator. ... Time zones are areas of the Earth that have adopted the same standard time, usually referred to as the local time. ... Longitude, sometimes denoted by the Greek letter λ, describes the location of a place on Earth east or west of a north-south line called the Prime Meridian. ... Axial tilt is an astronomical term regarding the inclination angle of a planets rotational axis in relation to its orbital plane. ... Insert non-formatted text here The Northern Hemisphere is the half of a planets surface (or celestial sphere) that is north of the equator (the word hemisphere literally means half ball). On the Earth, the Northern Hemisphere contains most of the land and population. ... The December solstice occurs on December 21 or December 22 of most years, and is known by different names in different hemispheres of Earth: Winter solstice in the Northern Hemisphere; the shortest day of the year. ... December 21 is the 355th day of the year (356th in leap years) in the Gregorian calendar. ... Illumination of Earth by the sun on the northern hemisphere summer solstice The summer solstice is an astronomical term regarding the position of the sun in relation to the celestial equator. ... June 21 is the 172nd day of the year (173rd in leap years) in the Gregorian calendar, with 193 days remaining. ... The Southern Hemisphere is the half of a planets surface (or celestial sphere) that is south of the equator (the word hemisphere literally means half ball). On Earth it contains five continents (Antarctica, Australia, most of South America, parts of Africa and Asia) as well as four oceans (South... This article or section needs a complete rewrite for the reasons listed on the talk page. ... In tourist areas, the equator is often marked on the sides of roads The Equator is an imaginary circle drawn around a planet (or other astronomical object) at a distance halfway between the poles. ... Noon is the time exactly halfway through the day, written 12:00 in the 24-hour clock and 12:00 pm in the 12-hour clock. ... The analemma photographed, looking east in the northern hemisphere. ...

Due to Earth's axial tilt, the direction of sunset is always to the northwest from the March equinox to the September equinox, and to the southwest from the September equinox to the March equinox.

As sunrise and sunset are calculated from the leading and trailing edges of the Sun, and not the centre, this slightly increases the duration of "day" relative to "night". Further, because the light from the Sun is bent by the atmospheric refraction, the Sun is still seen after it is below the horizon. This effect is a daily illusion along with sunrise. Atmospheric refraction is the deviation of light or other electromagnetic wave from a straight line as it passes through the atmosphere due to the variation in air density as a function of altitude. ...

As a visual motif, sunset is often associated with summer, and (particularly when paired with a coconut palm) beach living and surfing culture. This may be due in the first instance to people spending more time outdoors in the evening during summer than during winter, and also because pictures of sunsets over the sea are often more spectacular than daytime beach scenes (see images below). Sunset is also a symbol of west, old age, ending, and closure. In art, a motif is a repeated idea, pattern, image, or theme. ... Binomial name Cocos nucifera L.. The Coconut Palm (Cocos nucifera L.), is a member of the Family Arecaceae (palm family). ... The Beach in Calella, Spain. ... Buttons Kaluhiokalani at Banzai Pipeline, December 1981 Surfing is a surface water sport in which the participant is carried by a breaking wave on a surfboard. ...

Moonrise over red and blue haze, known as the "Belt of Venus", it is an inverted sunset. Image File history File links Download high resolution version (1600x1067, 141 KB) Cloudy sunset File links The following pages link to this file: Sunset User:Fir0002/Fir0002 gallery User:Fir0002/Fir0002 gallery/20D/Scenery ... Image File history File links Download high resolution version (1600x1200, 278 KB) Moonrise over red and blue haze, known as the Belt of Venus it is an inverted sunset File links The following pages link to this file: Moon Haze ...

Image File history File links Download high resolution version (1600x1131, 147 KB) Sunset with funnel style clouds File links The following pages link to this file: Sunset Wikipedia:Featured pictures visible User talk:Fir0002 User:Fir0002/Fir0002 gallery User:Fir0002/Fir0002 gallery/Featured Pictures Wikipedia:Featured pictures thumbs 03 Wikipedia...

See also

• Sunrise
• Sunrise equation
• Day length
• Diffuse sky radiation
• Twilight
• Afterglow

The Rayleigh effect, seconds before sunrise in New Zealand Sunrise, also called sunup in some American English dialects, is the time at which the first part of the Sun appears above the horizon in the east. ... The sunrise equation as follows can be used to derive the time of sunrise and sunset for any solar declination and latitude in terms of local solar time when sunrise and sunset actually occur: cos(ωo) = -tan(φ)×tan(δ) where ωo is the hour angle in degree at either sunrise (when... Day length as a function of latitude and Julian day. ... Spectrum of blue sky clearly showing solar Fraunhofer lines and atmospheric water absorption band. ... It has been suggested that this article or section be merged with Dawn. ... AfterGlow (band) Left-Right, Joe Hudson, Alex Boba, Will Hardcastle, Ben Elseworthy, Alex Ruckledge. ...

External links

Wikimedia Commons has media related to:

Sunset

• Sunrise and sunset calculator
• Full physical explanation in simple terms
• Calculation of Length of Day (Formulas and Graphs)