The Moon is an astronomical body that orbits planet Earth and is Earth's only permanent natural satellite. It is the fifth-largest natural satellite in the Solar System, the largest among planetary satellites relative to the size of the planet that it orbits; the Moon is after Jupiter's satellite Io the second-densest satellite in the Solar System among those whose densities are known. The Moon is thought to have formed not long after Earth; the most accepted explanation is that the Moon formed from the debris left over after a giant impact between Earth and a Mars-sized body called Theia. The Moon is in synchronous rotation with Earth, thus always shows the same side to Earth, the near side; the near side is marked by dark volcanic maria that fill the spaces between the bright ancient crustal highlands and the prominent impact craters. After the Sun, the Moon is the second-brightest visible celestial object in Earth's sky, its surface is dark, although compared to the night sky it appears bright, with a reflectance just higher than that of worn asphalt.
Its gravitational influence produces the ocean tides, body tides, the slight lengthening of the day. The Moon's average orbital distance is 1.28 light-seconds. This is about thirty times the diameter of Earth; the Moon's apparent size in the sky is the same as that of the Sun, since the star is about 400 times the lunar distance and diameter. Therefore, the Moon covers the Sun nearly during a total solar eclipse; this matching of apparent visual size will not continue in the far future because the Moon's distance from Earth is increasing. The Moon was first reached in September 1959 by an unmanned spacecraft; the United States' NASA Apollo program achieved the only manned lunar missions to date, beginning with the first manned orbital mission by Apollo 8 in 1968, six manned landings between 1969 and 1972, with the first being Apollo 11. These missions returned lunar rocks which have been used to develop a geological understanding of the Moon's origin, internal structure, the Moon's history. Since the Apollo 17 mission in 1972, the Moon has been visited only by unmanned spacecraft.
Both the Moon's natural prominence in the earthly sky and its regular cycle of phases as seen from Earth have provided cultural references and influences for human societies and cultures since time immemorial. Such cultural influences can be found in language, lunar calendar systems and mythology; the usual English proper name for Earth's natural satellite is "the Moon", which in nonscientific texts is not capitalized. The noun moon is derived from Old English mōna, which stems from Proto-Germanic *mēnô, which comes from Proto-Indo-European *mḗh₁n̥s "moon", "month", which comes from the Proto-Indo-European root *meh₁- "to measure", the month being the ancient unit of time measured by the Moon; the name "Luna" is used. In literature science fiction, "Luna" is used to distinguish it from other moons, while in poetry, the name has been used to denote personification of Earth's moon; the modern English adjective pertaining to the Moon is lunar, derived from the Latin word for the Moon, luna. The adjective selenic is so used to refer to the Moon that this meaning is not recorded in most major dictionaries.
It is derived from the Ancient Greek word for the Moon, σελήνη, from, however derived the prefix "seleno-", as in selenography, the study of the physical features of the Moon, as well as the element name selenium. Both the Greek goddess Selene and the Roman goddess Diana were alternatively called Cynthia; the names Luna and Selene are reflected in terminology for lunar orbits in words such as apolune and selenocentric. The name Diana comes from the Proto-Indo-European *diw-yo, "heavenly", which comes from the PIE root *dyeu- "to shine," which in many derivatives means "sky and god" and is the origin of Latin dies, "day"; the Moon formed 4.51 billion years ago, some 60 million years after the origin of the Solar System. Several forming mechanisms have been proposed, including the fission of the Moon from Earth's crust through centrifugal force, the gravitational capture of a pre-formed Moon, the co-formation of Earth and the Moon together in the primordial accretion disk; these hypotheses cannot account for the high angular momentum of the Earth–Moon system.
The prevailing hypothesis is that the Earth–Moon system formed after an impact of a Mars-sized body with the proto-Earth. The impact blasted material into Earth's orbit and the material accreted and formed the Moon; the Moon's far side has a crust, 30 mi thicker than that of the near side. This is thought to be; this hypothesis, although not perfect best explains the evidence. Eighteen months prior to an October 1984 conference on lunar origins, Bill Hartmann, Roger Phillips, Jeff Taylor challenged fellow lunar scientists: "You have eighteen months. Go back to your Apollo data, go back to your computer, do whatever you have to, but make up your mind. Don't come to our conference unless you have something to say about the Moon's birth." At the 1984 conference at Kona, the giant impact hypothesis emerged as the most consensual theory. Before the conference, there were parti
Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a giant planet with a mass one-thousandth that of the Sun, but two-and-a-half times that of all the other planets in the Solar System combined. Jupiter and Saturn are gas giants. Jupiter has been known to astronomers since antiquity, it is named after the Roman god Jupiter. When viewed from Earth, Jupiter can reach an apparent magnitude of −2.94, bright enough for its reflected light to cast shadows, making it on average the third-brightest natural object in the night sky after the Moon and Venus. Jupiter is composed of hydrogen with a quarter of its mass being helium, though helium comprises only about a tenth of the number of molecules, it may have a rocky core of heavier elements, but like the other giant planets, Jupiter lacks a well-defined solid surface. Because of its rapid rotation, the planet's shape is that of an oblate spheroid; the outer atmosphere is visibly segregated into several bands at different latitudes, resulting in turbulence and storms along their interacting boundaries.
A prominent result is the Great Red Spot, a giant storm, known to have existed since at least the 17th century when it was first seen by telescope. Surrounding Jupiter is a powerful magnetosphere. Jupiter has 79 known moons, including the four large Galilean moons discovered by Galileo Galilei in 1610. Ganymede, the largest of these, has a diameter greater than that of the planet Mercury. Jupiter has been explored on several occasions by robotic spacecraft, most notably during the early Pioneer and Voyager flyby missions and by the Galileo orbiter. In late February 2007, Jupiter was visited by the New Horizons probe, which used Jupiter's gravity to increase its speed and bend its trajectory en route to Pluto; the latest probe to visit the planet is Juno, which entered into orbit around Jupiter on July 4, 2016. Future targets for exploration in the Jupiter system include the probable ice-covered liquid ocean of its moon Europa. Astronomers have discovered nearly 500 planetary systems with multiple planets.
These systems include a few planets with masses several times greater than Earth's, orbiting closer to their star than Mercury is to the Sun, sometimes Jupiter-mass gas giants close to their star. Earth and its neighbor planets may have formed from fragments of planets after collisions with Jupiter destroyed those super-Earths near the Sun; as Jupiter came toward the inner Solar System, in what theorists call the grand tack hypothesis, gravitational tugs and pulls occurred causing a series of collisions between the super-Earths as their orbits began to overlap. Researchers from Lund University found that Jupiter's migration went on for around 700,000 years, in a period 2-3 million years after the celestial body started its life as an ice asteroid far from the sun; the journey inwards in the solar system followed a spiraling course in which Jupiter continued to circle around the sun, albeit in an tight path. The reason behind the actual migration relates to gravitational forces from the surrounding gases in the solar system.
Jupiter moving out of the inner Solar System would have allowed the formation of inner planets, including Earth. Jupiter is composed of gaseous and liquid matter, it is the largest of hence its largest planet. It has a diameter of 142,984 km at its equator; the average density of Jupiter, 1.326 g/cm3, is the second highest of the giant planets, but lower than those of the four terrestrial planets. Jupiter's upper atmosphere is about 88–92% hydrogen and 8–12% helium by percent volume of gas molecules. A helium atom has about four times as much mass as a hydrogen atom, so the composition changes when described as the proportion of mass contributed by different atoms. Thus, Jupiter's atmosphere is 75% hydrogen and 24% helium by mass, with the remaining one percent of the mass consisting of other elements; the atmosphere contains trace amounts of methane, water vapor and silicon-based compounds. There are traces of carbon, hydrogen sulfide, oxygen and sulfur; the outermost layer of the atmosphere contains crystals of frozen ammonia.
The interior contains denser materials—by mass it is 71% hydrogen, 24% helium, 5% other elements. Through infrared and ultraviolet measurements, trace amounts of benzene and other hydrocarbons have been found; the atmospheric proportions of hydrogen and helium are close to the theoretical composition of the primordial solar nebula. Neon in the upper atmosphere only consists of 20 parts per million by mass, about a tenth as abundant as in the Sun. Helium is depleted to about 80% of the Sun's helium composition; this depletion is a result of precipitation of these elements into the interior of the planet. Based on spectroscopy, Saturn is thought to be similar in composition to Jupiter, but the other giant planets Uranus and Neptune have less hydrogen and helium and more ices and are thus now termed ice giants. Jupiter's mass is 2.5 times that of all the other planets in the Solar System combined—this is so massive that its barycenter with the Sun lies above the Sun's surface at 1.068 solar radii from the Sun's center.
Jupiter is much larger than Earth and less dense: its volume is that of about 1,321 Earths, but it is only 318 times as massive. Jupiter's radius is about 1/10 the radius of the Sun, its mass is 0.001 times the mass of the Sun, so the densities of the two bodies are similar. A "Jupiter mass" is used as a u
Chinese mythology is mythology, passed down in oral form or recorded in literature in the geographic area now known as "China". Chinese mythology includes many varied myths from cultural traditions. Chinese mythology is far from monolithic, not being an integrated system among just Han people. Chinese mythology is encountered in the traditions of various classes of people, geographic regions, historical periods including the present, from various ethnic groups. China is the home of many mythological traditions, including that of Han Chinese and their Huaxia predecessors, as well as Tibetan mythology, Turkic mythology, Korean mythology, many others. However, the study of Chinese mythology tends to focus upon material in Chinese language. Much of the mythology involves exciting stories full of fantastic people and beings, the use of magical powers taking place in an exotic mythological place or time. Like many mythologies, Chinese mythology has in the past been believed to be, at least in part, a factual recording of history.
Along with Chinese folklore, Chinese mythology forms an important part of Chinese folk religion. Many stories regarding characters and events of the distant past have a double tradition: ones which present a more historicized or euhemerized version and ones which presents a more mythological version. Many myths involve the cosmology of the universe and its deities and inhabitants; some mythology involves creation myths, the origin of things and culture. Some involve the origin of the Chinese state; some myths present a chronology of prehistoric times, many of these involve a culture hero who taught people how to build houses, or cook, or write, or was the ancestor of an ethnic group or dynastic family. Mythology is intimately related to ritual. Many myths are oral associations with ritual acts, such as dances and sacrifices. There has been an extensive interaction between Chinese mythology and Confucianism and Buddhism. Elements of pre-Han dynasty mythology such as those in Classic of Mountains and Seas were adapted into these belief systems as they developed, or were assimilated into Chinese culture.
Elements from the teachings and beliefs of these systems became incorporated into Chinese mythology. For example, the Taoist belief of a spiritual paradise became incorporated into mythology as the place where immortals and deities dwelt. Sometimes mythological and religious ideas have become widespread across China's many regions and diverse ethnic societies. In other cases beliefs are more limited to certain social groups, for example the veneration of white stones by the Qiang. One mythological theme that has a long history and many variations involves a shamanic world view, for example in the cases of Mongolian shamanism among the Mongols, Hmong shamanism among the Miao people, the shamanic beliefs of the Qing dynasty from 1643 to 1912, derived from the Manchus. Politically, mythology was used to legitimize the dynasties of China, with the founding house of a dynasty claiming divine descent. True mythology is distinguished from philosophical theories. Elaborations on the Wu Xing are not part of mythology, although belief in five elements could appear.
The Hundred Schools of Thought is a phrase suggesting the diversity of philosophical thought that developed during the Warring States of China. And subsequently, philosophical movements had a complicated relationship with mythology. However, as far as they influence or are influenced by mythology, John C. Ferguson divides the philosophical camps into two rough halves, a Liberal group and a Conservative group; the liberal group being associated with the idea of individuality and change, for example as seen in the mythology of divination in China, such as the mythology of the dragon horse that delivered the eight bagua diagrams to Fu Xi, methods of individual empowerment as seen in the Yi Jing. The Liberal tendency is towards individual freedom and Nature; the relationship of the Conservative philosophies to mythology is seen in the legendary Nine Tripod Cauldrons, mythology about the emperors and central bureaucratic governance, written histories, ceremonial observances, subordination of the individual to the social groups of family and state, a fixation on stability and enduring institutions.
The distinction between the Liberal and Conservative is general, but important in Chinese thought. Contradictions can be found in the details, however these are traditional, such as the embrace by Confucius of the philosophical aspects of the Yi Jing, the back-and-forth about the Mandate of Heaven wherein one dynasty ends and another begins based according to accounts where the Way of Heaven results in change, but a new ethical stable dynasty becomes established. Examples of this include the stories of Yi Yin, Tang of Shang and Jie of Xia or the similar fantastic stories around Duke of Zhou and King Zhou of Shang. Mythology exists in relationship with other aspects such as ritual. Various rituals are explained by mythology. For example, the ritual burning of mortuary banknotes, lighting fireworks, so on. A good example of the relationship of Chinese mythology and ritual is the Yubu known as the Steps or Paces of Yu. During the course of his activities in controlling the Great Flood, Yu was supposed to have so fatigued himself that he lost all the hair from his legs and developed a serious limp.
Daoist practitioners sometimes incorporate a curiously choreographed pedal locomotion into various rituals. Mythology and practice, on
In the Year of the Pig
In the Year of the Pig is an American documentary film directed by Emile de Antonio about American involvement in the Vietnam War. It was released in 1968 while the U. S. was in the middle of its military engagement, was politically controversial. In 1969, the film was nominated for the Academy Award for Best Documentary Feature. In 1990, Jonathan Rosenbaum characterized the film as "the first and best of the major documentaries about Vietnam"; the film, in black and white, contains much historical footage and many interviews. Those interviewed include Harry Ashmore, Daniel Berrigan, Philippe Devillers, David Halberstam, Roger Hilsman, Jean Lacouture, Kenneth P. Landon, Thruston B. Morton, Paul Mus, Charlton Osburn, Harrison Salisbury, Ilya Todd, John Toller, David K. Tuck, David Wurfel and John White. Produced during the Vietnam War, the film was greeted with hostility by many audiences, with bomb threats and vandalism directed at theaters that showed it. De Antonio cites the film as his personal favorite.
It features the ironic use of patriotic music, portrays Ho Chi Minh as a patriot to the Vietnamese people, asserts that Vietnam was always a single country rather than two. In the Year of the Pig was released as a region 1 DVD in 2005. In addition to the film, the DVD has audio commentary with director Emile de Antonio composed from archival sources, an interview with de Antonio, liner notes by de Antonio scholar Douglas Kellner. A still photograph used in the film that displayed Marine Corporal Michael Wynn was incorporated into the album cover for The Smiths' second album, Meat Is Murder; the insignia on Wynn's helmet was changed to "meat is murder". This image was again used for the box art of the 2005 DVD release of the film. In the Year of the Pig on IMDb
The zodiac is an area of the sky that extends 8° north or south of the ecliptic, the apparent path of the Sun across the celestial sphere over the course of the year. The paths of the Moon and visible planets are within the belt of the zodiac. In Western astrology, astronomy, the zodiac is divided into twelve signs, each occupying 30° of celestial longitude and corresponding to the constellations Aries, Gemini, Leo, Libra, Sagittarius, Capricorn and Pisces; the twelve astrological signs form a celestial coordinate system, or more an ecliptic coordinate system, which takes the ecliptic as the origin of latitude and the Sun's position at vernal equinox as the origin of longitude. The English word zodiac derives from zōdiacus, the Latinized form of the Ancient Greek zōidiakòs kýklos, meaning "cycle or circle of little animals". Zōidion is the diminutive of zōion; the name reflects the prominence of animals among the twelve signs. The zodiac was in use by the Roman era, based on concepts inherited by Hellenistic astronomy from Babylonian astronomy of the Chaldean period, which, in turn, derived from an earlier system of lists of stars along the ecliptic.
The construction of the zodiac is described in the Almagest. Although the zodiac remains the basis of the ecliptic coordinate system in use in astronomy besides the equatorial one, the term and the names of the twelve signs are today associated with horoscopic astrology; the term "zodiac" may refer to the region of the celestial sphere encompassing the paths of the planets corresponding to the band of about eight arc degrees above and below the ecliptic. The zodiac of a given planet is the band. By extension, the "zodiac of the comets" may refer to the band encompassing most short-period comets; the division of the ecliptic into the zodiacal signs originates in Babylonian astronomy during the first half of the 1st millennium BC. The zodiac draws on stars in earlier Babylonian star catalogues, such as the MUL. APIN catalogue, compiled around 1000 BC; some of the constellations can be traced further back, to Bronze Age sources, including Gemini "The Twins", from MAŠ. TAB. BA. GAL. GAL "The Great Twins", Cancer "The Crab", from AL.
LUL "The Crayfish", among others. Around the end of the 5th century BC, Babylonian astronomers divided the ecliptic into twelve equal "signs", by analogy to twelve schematic months of thirty days each; each sign contained thirty degrees of celestial longitude, thus creating the first known celestial coordinate system. According to calculations by modern astrophysics, the zodiac was introduced between 409 and 398 BC and within a few years of 401 BC Unlike modern astronomers, who place the beginning of the sign of Aries at the place of the Sun at the vernal equinox; the divisions do not correspond to where the constellations started and ended in the sky. The Sun in fact passed through at least 13, not 12 Babylonian constellations. In order to align with the number of months in a year, designers of the system omitted the major constellation Ophiuchus. Including smaller figures, astronomers have counted up to 21 eligible zodiac constellations. Changes in the orientation of the Earth's axis of rotation means that the time of year the sun is in a given constellation has changed since Babylonian times.
Because the division was made into equal arcs, 30° each, they constituted an ideal system of reference for making predictions about a planet's longitude. However, Babylonian techniques of observational measurements were in a rudimentary stage of evolution and they measured the position of a planet in reference to a set of "normal stars" close to the ecliptic as observational reference points to help positioning a planet within this ecliptic coordinate system. In Babylonian astronomical diaries, a planet position was given with respect to a zodiacal sign alone, less in specific degrees within a sign; when the degrees of longitude were given, they were expressed with reference to the 30° of the zodiacal sign, i.e. not with a reference to the continuous 360° ecliptic. In astronomical ephemerides, the positions of significant astronomical phenomena were computed in sexagesimal fractions of a degree. For daily ephemerides, the daily positions of a planet were not as important as the astrologically significant dates when the planet crossed from one zodiacal sign to the next.
Knowledge of the Babylonian zodiac is reflected in the Hebrew Bible. Some authors have linked the twelve tribes of Israel with the twelve signs and/or the lunar Hebrew calendar having 12 lunar months in a lunar year. Martin and others have argued that the arrangement of the tribes around the Tabernacle corresponded to the order of the Zodiac, with Judah, Reuben and Dan representing the middle signs of Leo, Aquarius and Scorpio, respectively; such connectio
Sun path, sometimes called day arc, refers to the daily and seasonal arc-like path that the Sun appears to follow across the sky as the Earth rotates and orbits the Sun. The Sun's path affects the length of daytime experienced and amount of daylight received along a certain latitude during a given season; the relative position of the Sun is a major factor in the heat gain of buildings and in the performance of solar energy systems. Accurate location-specific knowledge of sun path and climatic conditions is essential for economic decisions about solar collector area, landscaping, summer shading, the cost-effective use of solar trackers. Sun paths at any latitude and any time of the year can be determined from basic geometry; the Earth's axis of rotation tilts about 23.5 degrees, relative to the plane of Earth's orbit around the Sun. As the Earth orbits the Sun, this creates the 47° declination difference between the solstice sun paths, as well as the hemisphere-specific difference between summer and winter.
In the Northern Hemisphere, the winter sun rises in the southeast, transits the celestial meridian at a low angle in the south, sets in the southwest. It is on the south side of the house all day long. A vertical window facing south is effective for capturing solar thermal energy. For comparison, the winter sun in the Southern Hemisphere rises in the northeast, peaks out at a low angle in the north, sets in the northwest. There, the north-facing window would let in plenty of solar thermal energy to the house. In the Northern Hemisphere in summer, the Sun rises in the northeast, peaks out south of overhead point, sets in the northwest, whereas in the Southern Hemisphere in summer, the Sun rises in the southeast, peaks out north of overhead point, sets in the southwest. A simple latitude-dependent equator-side overhang can be designed to block 100% of the direct solar gain from entering vertical equator-facing windows on the hottest days of the year. Roll-down exterior shade screens, interior translucent-or-opaque window quilts, shutters, movable trellises, etc. can be used for hourly, daily or seasonal sun and heat transfer control.
Everywhere around the world during the equinoxes except for the poles, the sun rises due east and sets due west. In the Northern Hemisphere, the equinox sun peaks in the southern half of the sky, while in the Southern Hemisphere, that sun peaks in the northern half of the sky; when facing the equator, the sun appears to move from left to right in the Northern Hemisphere and from right to left in the Southern Hemisphere. The latitude -specific solar path differences are critical to effective passive solar building design, they are essential data for optimal overhang seasonal design. Solar designers must know the precise solar path angles for each location they design for, how they compare to place-based seasonal heating and cooling requirements. In the U. S. the precise location-specific altitude-and-azimuth seasonal solar path numbers are available from NOAA – the "equator side" of a building is south in the Northern Hemisphere, north in the Southern Hemisphere, where the peak summer solstice solar altitude occurs on December 21.
On the equator, the sun will be straight overhead and a vertical stick will cast no shadow at solar noon on the equinoxes. On the vernal equinox, north of the subsolar point the vertical stick's shadow will point a little westwards of true north reading 336.5° from true north and little eastwards of true south reading 156.5° from true north. On the autumnal equinox, north of the subsolar point, the shadow will point a little eastwards of true north reading 23.5° from true north. The same stick will cast no shadow on the summer solstice in the Northern Hemisphere when the subsolar point is on the Tropic of Cancer 23.44° north of equator. Although north of 23.44°N the shadow will point towards true north and south of 23.44°N the shadow will point towards true south. The reverse occurs on the winter solstice in the Northern Hemisphere when the subsolar point will be on the Tropic of Capricorn 23.44°S and a vertical stick will cast no shadow along that point. But north of the Tropic of Capricorn solar noon shadows will point towards true north and south of the Tropic of Capricorn shadows will point towards true south.
The solar noon shadows of objects on points beyond and below subsolar points will point towards true north and true south only when the solar declination has its maximum positive or maximum negative value. On the other hand, on the equinoxes when the sun is neither declined north nor south and solar time noon shadows point NNW north of the equator and SSE south of the equator on the vernal equinox. Within the polar circles, each year will experience at least one day when the Sun remains below the horizon for 24 hours, at least one day when the Sun remains above the horizon for 24 hours. In the middle latitudes (between the tropics and
Horology is the study of the measurement of time. Clocks, clockwork, hourglasses, timers, time recorders, marine chronometers, atomic clocks are all examples of instruments used to measure time. In current usage, horology refers to the study of mechanical time-keeping devices, while chronometry more broadly includes electronic devices that have supplanted mechanical clocks for the best accuracy and precision in time-keeping. People interested in horology are called horologists; that term is used both by people who deal professionally with timekeeping apparatus, as well as aficionados and scholars of horology. Horology and horologists have numerous organizations, both professional associations and more scholarly societies; the largest horological membership organisation globally is the NAWCC, the National Association of Watch and Clock Collectors, USA based, but has local chapters elsewhere. There are several specialized libraries devoted to the subject. One example is the Royal Greenwich Observatory, the source of the Prime Meridian, the home of the first marine timekeepers accurate enough to determine longitude.
Other horological museums in the London area include the Clockmakers' Museum, which re-opened at the Science Museum in October 2015, the horological collections at the British Museum, the Science Museum, the Wallace Collection. One of the more comprehensive museums dedicated to horology is the Musée international d'horlogerie in La Chaux-de-Fonds; the Musée d'Horlogerie du Locle is smaller but located nearby. One of the better horological museums in Germany is the Deutsches Uhrenmuseum in Furtwangen im Schwarzwald, in the Black Forest; the two leading specialised horological museums in North America are the National Watch and Clock Museum in Columbia and the American Clock and Watch Museum in Bristol, Connecticut. The eastern French city of Besançon has the Musée du Temps in the historic Palais Grenvelle. An example of a museum devoted to one particular type of clock is the Cuckooland Museum in the UK, which hosts the world's largest collection of antique cuckoo clocks. One of the most comprehensive horological libraries open to the public is the National Watch and Clock Library in Columbia, Pennsylvania.
Other good horological libraries providing public access are at the Musée international d'horlogerie in Switzerland, at the Deutsches Uhrenmuseum in Germany, at the Guildhall Library in London. Another museum dedicated to clocks is the Willard Clock Museum in Grafton, Massachusetts. Notable scholarly horological organizations include: American Watchmakers-Clockmakers Institute – AWCI Antiquarian Horological Society – AHS British Horological Institute – BHI Chronometrophilia Deutsche Gesellschaft für Chronometrie – DGC National Association of Watch and Clock Collectors – NAWCC BaselWorld Geneva Time Exhibition Salon International de la Haute Horlogerie Buddhist calendar Complication Daylight saving time History of timekeeping devices Hora ISO 8601 Kalachakra List of clock manufacturers List of watch manufacturers System time Winthrop Kellogg Edey Dictionary of Horology Beckett, Edmund, A Rudimentary Treatise on Clocks and Bells, 1903, from Project Gutenberg Berner, G. A. Illustrated Professional Dictionary of Horology, Federation of the Swiss Watch Industry FH 1961 - 2012 Daniels, Watchmaking, London: Philip Wilson Publishers, 1981 Grafton, Horology, a popular sketch of clock and watch making, London: Aylett and Jones, 1849 Perman, Stacy, A Grand Complication: The Race to Build the World's Most Legendary Watch, Atria Books, February 2013.