what is another name for the prime meridian
the IERS Reference Meridian
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or advocated in different regions and throughout history. The most widely used modern meridian is the IERS Reference Meridian. It is derived but deviates slightly from the Greenwich Meridian, which was selected as an international standard in 1884. The notion of longitude was developed by the Greek Eratosthenes (c. 276 BC – c. 195 BC) in Alexandria, and Hipparchus (c. 190 BC – c. 120 BC) in Rhodes, and applied to a large number of cities by the geographer Strabo (64/63 BC – c. 24 AD). But it was Ptolemy (c. AD 90 – c. AD 168) who first used
Prime meridian
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ideal International Terrestrial Reference System (ITRS) and its realization, the International Terrestrial Reference Frame (ITRF). A current convention on the Earth uses the opposite of the IRM as the basis for the International Date Line. On Earth, starting at the North Pole and heading south to the South Pole, the IERS Reference Meridian (as of 2016) passes through: As on the Earth, prime meridians must be arbitrarily defined. Often a landmark such as a crater is used; other times a prime meridian is defined by reference to another celestial object, or by magnetic fields. The prime meridians of the following
Prime meridian
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D.C., United States to be the common zero of longitude and standard of time reckoning throughout the world. The modern prime meridian, the IERS Reference Meridian, is placed very near this meridian and is the prime meridian that currently has the widest use. The modern prime meridian, based at the Royal Observatory, Greenwich, was established by Sir George Airy in 1851. The position of the Greenwich Meridian has been defined by the location of the Airy Transit Circle ever since the first observation was taken with it by Sir George Airy in 1851. Prior to that, it was defined by
Prime meridian
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1826 the Dutch navy switched to Greenwich by royal decree. Without the backing of the Dutch, the meridian of Tenerife was hardly used anymore. Tenerife meridian The Tenerife meridian was the prime meridian of choice for Dutch cartographers and navigators from the 1640s until the beginning of the 19th century. It lies at 16° 38′ 22″ W of the current international prime meridian, the IERS Reference Meridian through Greenwich. Cartographers like Mercator, Hondius and Blaeu played a significant role in the development of cartography around the turn of the seventeenth century. They were also among the first (in Europe) to
Tenerife meridian
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Tenerife meridian The Tenerife meridian was the prime meridian of choice for Dutch cartographers and navigators from the 1640s until the beginning of the 19th century. It lies at 16° 38′ 22″ W of the current international prime meridian, the IERS Reference Meridian through Greenwich. Cartographers like Mercator, Hondius and Blaeu played a significant role in the development of cartography around the turn of the seventeenth century. They were also among the first (in Europe) to deviate from the use of the Ferro meridian, which was based on the works of the Greek astronomer and geographer Ptolemy (c. AD 90
Tenerife meridian
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IERS Reference Meridian The IERS Reference Meridian (IRM), also called the International Reference Meridian, is the prime meridian (0° longitude) maintained by the International Earth Rotation and Reference Systems Service (IERS). It passes about 5.3 arcseconds east of George Biddell Airy's 1851 transit circle or at the latitude of the Royal Observatory, Greenwich. It is also the reference meridian of the Global Positioning System (GPS) operated by the United States Department of Defense, and of WGS84 and its two formal versions, the ideal International Terrestrial Reference System (ITRS) and its realization, the International Terrestrial Reference Frame (ITRF). The reason for
IERS Reference Meridian
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Starting at the North Pole and heading south to the South Pole, the IERS Reference Meridian passes through 8 countries: IERS Reference Meridian The IERS Reference Meridian (IRM), also called the International Reference Meridian, is the prime meridian (0° longitude) maintained by the International Earth Rotation and Reference Systems Service (IERS). It passes about 5.3 arcseconds east of George Biddell Airy's 1851 transit circle or at the latitude of the Royal Observatory, Greenwich. It is also the reference meridian of the Global Positioning System (GPS) operated by the United States Department of Defense, and of WGS84 and its two formal
IERS Reference Meridian
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two, diametrically opposite, stations must move in opposite directions by the same amount. The 180th meridian is opposite the IERS Reference Meridian and forms a great circle with it dividing the earth into Western Hemisphere and Eastern Hemisphere. Universal Time is notionally based on the WGS84 meridian. Because of changes in the rate of Earth's rotation, standard international time UTC can differ from the mean observed solar time at noon on the prime meridian by up to 0.9 second. Leap seconds are inserted periodically to keep UTC close to Earth's angular position relative to the Sun; see mean solar time.
IERS Reference Meridian
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Paris meridian The Paris meridian is a meridian line running through the Paris Observatory in Paris, France—now longitude 2°20′14.03″ east. It was a long-standing rival to the Greenwich meridian as the prime meridian of the world. The Paris meridian arc or French meridian arc (French: "la Méridienne de France") is the name of the meridian arc measured along the Paris meridian. The French meridian arc was important for French cartography, inasmuch as the triangulations of France began with the measurement of the French meridian arc. Moreover, the French meridian arc was important for geodesy as it was one of the
Paris meridian
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scientists determined that in the Ordnance Survey system the longitude of the international Greenwich meridian was not 0° but 0°00'00.417" (about 8 m) East. Besides the change of the reference line, imperfections of the surveying system added another discrepancy to the definition of the origin, so that the Bradley line itself is now 0°00'00.12" East of the Ordnance Survey Zero Meridian (about 2.3m). This old astronomical prime meridian has been replaced by a more precise prime meridian. When Greenwich was an active observatory, geographical coordinates were referred to a local oblate spheroid called a datum known as a geoid, whose
Royal Observatory, Greenwich
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planetographic systems have been defined: Prime meridian A prime meridian is a meridian (a line of longitude) in a geographic coordinate system at which longitude is defined to be 0°. Together, a prime meridian and its antimeridian (the 180th meridian in a 360°-system) form a great circle. This great circle divides the sphere, e.g., Earth, into two hemispheres. If one uses directions of East and West from a defined prime meridian, then they can be called the Eastern Hemisphere and the Western Hemisphere. A prime meridian is ultimately arbitrary, unlike an equator, which is determined by the axis of rotation—and
Prime meridian
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Prime meridian A prime meridian is a meridian (a line of longitude) in a geographic coordinate system at which longitude is defined to be 0°. Together, a prime meridian and its antimeridian (the 180th meridian in a 360°-system) form a great circle. This great circle divides the sphere, e.g., Earth, into two hemispheres. If one uses directions of East and West from a defined prime meridian, then they can be called the Eastern Hemisphere and the Western Hemisphere. A prime meridian is ultimately arbitrary, unlike an equator, which is determined by the axis of rotation—and various conventions have been used
Prime meridian
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Meridian Charter Township, Michigan Meridian Charter Township is a charter township of Ingham County in the U.S. state of Michigan. As of the 2010 census the township had a population of 39,688. Meridian Township is the local government unit that includes the unincorporated communities and census-designated places of Okemos and Haslett. Meridian Township is the third largest municipality in the Lansing-East Lansing Metropolitan Statistical Area. Meridian Township takes its name from the fact that the Michigan meridian, the prime north-south survey line, comprises the eastern border of the township. It is from this line that all townships were surveyed and
Meridian Charter Township, Michigan
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as a standard, although the world’s navigators have generally come to accept the reference longitudes tabulated by the British. The reference longitude adopted by the British became known as the Prime Meridian and is now accepted by most nations as the starting point for all longitude measurements. The Prime Meridian of zero degrees longitude runs along the meridian passing through the Royal Observatory at Greenwich, England. Longitude is measured east and west from the Prime Meridian. To determine "longitude by chronometer," a navigator requires a chronometer set to the local time at the Prime Meridian. Local time at the Prime
Longitude by chronometer
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Greenwich prime meridian and the plane passing through the Earth's rotation axis on the ITRF zero meridian are effectively parallel. However, the claim, found, e.g., in a BBC article that this difference between astronomical and geodetic coordinates means that any measurements of transit time across the IRTF zero meridian will occur 0.352 seconds (or 0.353 sidereal seconds) before the transit across the "intended meridian" is based on a failure of understanding. The explanation by Malys et al. on the other hand is both lucid and correct. As of 2018 the Greenwich meridian passes through: Prime meridian (Greenwich) A prime meridian,
Prime meridian (Greenwich)
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as "Di O Nysos, DON" ("dondon" is French slang for "fat woman"), an otherworldly being who organises funerals for the dead who are still living in her new Citroen 2CV (the make of car she was killed in). The term "Rose Line" as the Paris Meridian was given by Dan Brown in his novel "The Da Vinci Code" as an alternate name for "the world's first prime meridian", identified as the Paris Meridian. Brown's novel also conflates this meridian with a gnomon in the Parisian church of Saint-Sulpice marked in the floor with a brass line, as did the 1967
Rose Line
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as the international Prime Meridian. On August 12, 1912, the United States adopted the Prime Meridian of Greenwich for all uses, domestic and international. 32nd meridian west from Washington The 32nd meridian of longitude west from Washington is a line of longitude approximately 109°02′48″ west of the Prime Meridian of Greenwich. In the United States of America, the meridian 32 degrees west of the Washington Meridian defines the western boundaries of the State of Colorado and the State of New Mexico and the eastern boundaries of the State of Utah and the State of Arizona. On February 28, 1861, the
32nd meridian west from Washington
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is equal to the colongitude plus 180°. Longitude on the Moon is measured both east and west from its prime meridian. When no direction is specified, east is positive and west is negative. Roughly speaking, the Moon's prime meridian lies near the center of the Moon's disc as seen from Earth. For precise applications, many coordinate systems have been defined for the Moon, each with a slightly different prime meridian. The IAU recommends the "mean Earth/polar axis" system, in which the prime meridian is the average direction (from the Moon's center) of the Earth's center. Selenographic coordinates Selenographic coordinates are
Selenographic coordinates
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The Meridian Rock The Meridian Rock is set at the Port of Tema, Ghana, on the platform of Meridian Port Services Limited (MPS). It is a rock marking the line of the Greenwich Meridian, the World’s prime meridian for Longitude and Time. It was in 1884 that the Greenwich Meridian was established by agreement as the line of zero Longitude forming the bases for navigation and time keeping throughout the world. Running from the North to the South Pole and separating the Eastern Hemisphere from the Western. Also, this prime Meridian Line (0°00’00.00”E/W) passes through the center of Meridian Port
The Meridian Rock
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used to reduce civilian energy consumption. One of the earliest known descriptions of "standard time" in India appeared in the 4th century CE astronomical treatise Surya Siddhanta. Postulating a spherical earth, the book described the thousands years old customs of the prime meridian, or zero longitude, as passing through "Avanti", the ancient name for the historic city of Ujjain, and "Rohitaka", the ancient name for Rohtak (), a city near the Kurukshetra. The day used by ancient Indian astronomers began at sunrise at the prime meridian of Ujjain, and was divided into smaller time units in the following manner: Taking
Time in India
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equipment needed for broadcast. In February 2010, Ofcom inspected and approved the studios and transmission equipment, and 107 Meridian FM started officially broadcasting over 107Mhz FM on 1 March 2010 at 7am GMT. In early 2015, Ofcom approved the renewal of 107 Meridian FM's broadcast license until 2020. The studios were originally located in East Court Mansion together with the East Grinstead Town Council offices, but moved to the Jubilee Community Centre in Charlwoods Road in January 2010. The station took its name from the Greenwich Prime Meridian which runs through East Grinstead. It is unconnected with television broadcaster ITV
107 Meridian FM
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to use the Paris meridian for several decades. In the 18th century, London lexicographer Malachy Postlethwayt published his African maps showing the "Meridian of London" intersecting the Equator a few degrees west of the later meridian and Accra, Ghana. The plane of the prime meridian is parallel to the local gravity vector at the Airy transit circle () of the Greenwich observatory. The prime meridian was therefore long symbolised by a brass strip in the courtyard, now replaced by stainless steel, and since 16 December 1999, it has been marked by a powerful green laser shining north across the London
Prime meridian (Greenwich)
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measuring 20,003.93 km (12,429.9 miles). The first prime meridian was set by Eratosthenes in 276 BCE. This prime meridian was used to provide measurement of the earth, but had many issues because of the lack of latitude measurement. Many years later around the 19th century there was still concerns of the prime meridian. The idea of having one prime meridian came from William Parker Snow, because he realized the confusion of having multiple prime meridian locations. Many of theses geographical locations were traced back to the ancient Greeks, and others were created by several nations. Multiple locations for the geographical
Meridian (geography)
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Prime meridian (Greenwich) A prime meridian, based at the Royal Observatory, Greenwich, in London, England, was established by Sir George Airy in 1851. By 1884, over two-thirds of all ships and tonnage used it as the reference meridian on their charts and maps. In October of that year, at the behest of US President Chester A. Arthur, 41 delegates from 25 nations met in Washington, D.C., United States, for the International Meridian Conference. This conference selected the meridian passing through Greenwich as the official prime meridian due to its popularity. However, France abstained from the vote, and French maps continued
Prime meridian (Greenwich)
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shore of the Mediterranean, 10–13 degrees to the east of Alexandria (the prime meridian previously set by Ptolemy) and 70 degrees to the west of Baghdad. Most medieval Muslim geographers continued to use al-Khwarizmi's prime meridian. Other prime meridians used were set by Abū Muhammad al-Hasan al-Hamdānī and Habash al-Hasib al-Marwazi at Ujjain, a centre of Indian astronomy, and by another anonymous writer at Basra. The Arab geographer, Muhammad al-Idrisi, produced his medieval atlas, "Tabula Rogeriana" or "The Recreation for Him Who Wishes to Travel Through the Countries", in 1154. He incorporated the knowledge of Africa, the Indian Ocean and
History of cartography
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United Kingdom Ordnance Survey Zero Meridian The United Kingdom Ordnance Survey Zero Meridian is the prime meridian used by the Ordnance Survey (OSGB36 datum). It is about six metres to the west of the Airy meridian marked at Greenwich. When the first Ordnance Survey map was published in 1801, the official Prime Meridian of Great Britain was the one established by the third Astronomer Royal, James Bradley. When Airy's new Prime Meridian ("new" by virtue of Sir George Airy's instrument being placed in a room next to that housing James Bradley's instrument) superseded it fifty years later in 1851, the
United Kingdom Ordnance Survey Zero Meridian
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Ordnance Survey simply continued to use Bradley's. United Kingdom Ordnance Survey Zero Meridian The United Kingdom Ordnance Survey Zero Meridian is the prime meridian used by the Ordnance Survey (OSGB36 datum). It is about six metres to the west of the Airy meridian marked at Greenwich. When the first Ordnance Survey map was published in 1801, the official Prime Meridian of Great Britain was the one established by the third Astronomer Royal, James Bradley. When Airy's new Prime Meridian ("new" by virtue of Sir George Airy's instrument being placed in a room next to that housing James Bradley's instrument) superseded
United Kingdom Ordnance Survey Zero Meridian
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marked the division between the Argyle and Brant Districts, as well as the mark between neighboring Rockwood and Woodlands Municipalities. As the local residents were living on either side of the Prime Meridian, several institutions derive their name by combining the words: Brant-Argyle. The Prime Meridian was the starting point during the early 1870s for crews surveying Western Canada. The Section, Township & Range system of addressing properties across the prairies begins on this line, dividing east from west. Just North of the town, is the ancient Lake Agassiz beach ridge. About 10,000 years ago, this huge inland lake, the
Argyle, Manitoba
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responsible for its delineation. Davies (crater) Davies is a crater on Mars located at 46°N 0°E on the fringe of Acidalia Planitia near Arabia Terra. It is approximately 48 km in diameter. The crater's name was formally approved by the IAU in 2006. It was named in honor of Merton Davies (1917-2001), a pioneer in the cartography of planetary bodies. An employee of the RAND Corporation, he assisted NASA in mapping Mars with colleagues Gérard de Vaucouleurs and Harold Masursky and defined the prime meridian of Mars as passing through the crater Airy-0. Davies Crater lies on the prime meridian,
Davies (crater)
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Almanac" retained Maskelyne's calculations from Greenwich—in spite of the fact that every other table in the "Connaissance des Temps" considered the Paris meridian as the prime." In 1884, at the International Meridian Conference in Washington, D.C., 22 countries voted to adopt the Greenwich meridian as the prime meridian of the world. The French argued for a neutral line, mentioning the Azores and the Bering Strait, but eventually abstained and continued to use the Paris meridian until 1911. In October 1884 the Greenwich Meridian was selected by delegates (forty-one delegates representing twenty-five nations) to the International Meridian Conference held in Washington,
Prime meridian
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the ITV network while another Sunday night favourite, "Where the Heart Is", transferred production from Anglia Television to Meridian in 2002 - the station's last major contribution at a network level. ITV Meridian ITV Meridian (previously Meridian Broadcasting) is the holder of the ITV franchise for the South and South East of England. The station was launched on 1 January 1993, replacing previous broadcaster Television South, and is owned and operated by ITV plc, under the licensee of ITV Broadcasting Limited. Meridian Broadcasting Ltd was one of several (but not all) ITV plc-owned regional companies to have its legal name
ITV Meridian
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Mars Time (MTC) or Martian Coordinated Time is a proposed Mars analog to Universal Time (UT1) on Earth. It is defined as the mean solar time at Mars's prime meridian. The prime meridian was first proposed by German astronomers Wilhelm Beer and Johann Heinrich Mädler in 1830 as marked by the fork in the albedo feature later named Sinus Meridiani by Italian astronomer Giovanni Schiaparelli. This convention was readily adopted by the astronomical community, the result being that Mars had a universally accepted prime meridian half a century before the International Meridian Conference of 1884 established one for Earth. The
Timekeeping on Mars
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Central Meridian used to be based on a meridian located at the old observatory in Stockholm, but today it is based on the Prime Meridian at Greenwich. The numbering system's first digit represents the largest distance, followed by what can be seen as fractional decimal digits (though without an explicit decimal point). Therefore X 65 is located half way between X 6 and X 7. The coordinate grid is specified using two numbers, named X and Y, X being the south–north axis and Y the west–east axis. Two seven-digit numbers are sufficient to specify a location with a one m
Swedish grid
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previous students that attended the school. The school had previously been called Addington High School and before that Fairchildes School. The Prime Meridian passes straight through the school playground, hence the current name. Meridian High School (London) Meridian High School is a coeducational secondary school with academy status, located in the New Addington area of the London Borough of Croydon, England. The School takes its pupils mainly from the Addington, New Addington, Forestdale, Selsdon and Shirley areas. In January 2007, strong winds swept the roof of the school off. No-one was harmed and the school was fully repaired by April
Meridian High School (London)
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International Meridian Conference The International Meridian Conference was a conference held in October 1884 in Washington, D.C., in the United States, to determine a prime meridian for international use. The conference was held at the request of U.S. President Chester A. Arthur. The subject to discuss was the choice of "a meridian to be employed as a common zero of longitude and standard of time reckoning throughout the world". It resulted in the recommendation of the Greenwich Meridian as the international standard for zero degrees longitude. By the 1870s there was pressure both to establish a prime meridian for worldwide
International Meridian Conference
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Davies (crater) Davies is a crater on Mars located at 46°N 0°E on the fringe of Acidalia Planitia near Arabia Terra. It is approximately 48 km in diameter. The crater's name was formally approved by the IAU in 2006. It was named in honor of Merton Davies (1917-2001), a pioneer in the cartography of planetary bodies. An employee of the RAND Corporation, he assisted NASA in mapping Mars with colleagues Gérard de Vaucouleurs and Harold Masursky and defined the prime meridian of Mars as passing through the crater Airy-0. Davies Crater lies on the prime meridian, appropriate because Davies was
Davies (crater)
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observations made at the Royal Greenwich Observatory (RGO). The principal meridian of that observatory was chosen in 1884 by the International Meridian Conference to be the Prime Meridian. GMT either by that name or as 'mean time at Greenwich' used to be an international time standard, but is no longer so; it was initially renamed in 1928 as Universal Time (UT) (partly as a result of ambiguities arising from the changed practice of starting the astronomical day at midnight instead of at noon, adopted as from 1 January 1925). The more current refined version of UT, UT1, is still in
Time standard
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night sky. Global Positioning System (GPS) receivers show that the marking strip for the prime meridian at Greenwich is not exactly at zero degrees, zero minutes, and zero seconds but at approximately 5.3 seconds of arc to the west of the meridian (meaning that the meridian appears to be 102.478 metres east). In the past, this offset has been attributed to the establishment of reference meridians for space-based location systems such as WGS 84 (which GPS relies on) or that errors gradually crept into the International Time Bureau timekeeping process. The actual reason for the discrepancy is that the marking
Prime meridian (Greenwich)
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practice to use a nation's capital as the starting point, but other locations were also used. While British cartographers had long used the Greenwich meridian in London, other references were used elsewhere, including El Hierro, Rome, Copenhagen, Jerusalem, Saint Petersburg, Pisa, Paris (see the article "Paris meridian"), Philadelphia, and Washington D.C. In 1884 the International Meridian Conference adopted the Greenwich meridian as the "universal Prime Meridian" or "zero point of longitude". Longitude is given as an angular measurement ranging from 0° at the Prime Meridian to +180° eastward and −180° westward. The Greek letter λ (lambda), is used to denote
Longitude
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dye (fluorescent sodium salt); crawling through chutes or large tubs of rotting garbage; kissing the Royal Baby's belly coated with axle grease, hair chopping, etc.), largely for the entertainment of the Shellbacks. Once the ceremony is complete, a Pollywog receives a certificate declaring his new status. Another rare status is the "Golden Shellback", a person who has crossed the Equator at the 180th meridian. The rarest Shellback status is that of the "Emerald Shellback" (USA), or "Royal Diamond Shellback" (Commonwealth), which is received after crossing the Equator at the prime meridian, near the Null Island weather buoy. When a ship
Line-crossing ceremony
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definition of the Martian prime meridian has since been refined on the basis of spacecraft imagery as the center of the crater Airy-0 in Terra Meridiani. The name "MTC" is intended to parallel the Terran Coordinated Universal Time (UTC), but this is somewhat misleading: what distinguishes UTC from other forms of UT is its leap seconds, but MTC does not use any such scheme. MTC is more closely analogous to UT1. Use of the term "Martian Coordinated Time" as a planetary standard time first appeared in a journal article in 2000. The abbreviation "MTC" was used in some versions of
Timekeeping on Mars
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made their first attempt to leave for the Dutch Republic in 1607. The ruined Hussey Tower is all that remains of a medieval brick fortified house. east, Rochford Tower is another medieval tower house. In Skirbeck Quarter, on the right bank of The Haven, is the Black Sluice, the outfall of the South Forty-Foot Drain. The Prime Meridian passes through the eastern side of Boston, marked by the fairly modern, suburban Meridian Road (), which straddles the line the road was named after. The annual Boston May Fair has been held in the town since at least 1125. This fair
Boston, Lincolnshire
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and territories created between 1861 and 1868. The completion of the first permanent transatlantic telegraph cable on July 28, 1866, allowed the United States Naval Observatory at Washington, D.C. to be synchronized with the Royal Observatory at Greenwich. The need for a separate national meridian for the United States gradually faded, and in 1884, U.S. President Chester A. Arthur called the International Meridian Conference in Washington, D.C. which selected the meridian of the Royal Observatory at Greenwich as the international Prime Meridian. On August 12, 1912, the United States adopted the Prime Meridian of Greenwich for all uses domestic and
25th meridian west from Washington
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ellipses (often called great circles), which converge at the North and South Poles. The meridian of the British Royal Observatory in Greenwich, in south-east London, England, is the international prime meridian, although some organizations—such as the French Institut Géographique National—continue to use other meridians for internal purposes. The prime meridian determines the proper Eastern and Western Hemispheres, although maps often divide these hemispheres further west in order to keep the Old World on a single side. The antipodal meridian of Greenwich is both 180°W and 180°E. This is not to be conflated with the International Date Line, which diverges from
Geographic coordinate system
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featured an exploding mix of orange, yellow and blue, which came together to form the distinctive sun/moon face logo. The unusual logo design was reportedly inspired by maritime images (the sun/moon face is a recurring feature on compasses, sextants and other nautical artefacts used in the navigation of ships), appropriately reflecting the south's long seafaring history. The name "Meridian", which derives from the Latin "meridionālis" meaning "of the south", may also be linked to the Prime Meridian (the boundary between the Western and Eastern Hemispheres of the globe, and a key landmark in the measurement of time), which passes through
ITV Meridian
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celestial body. The intersection between this line and the celestial body's surface is the sub-Earth point. The central meridian is the meridian going through the sub-Earth point. Because of the body's rotation and orbital alignment with the observer the central meridian changes with time, as it is based on the observer's point of view. For example, consider the Earth as seen from the Moon. There will be a meridian going through the centre of the Earth's visible disc (for example 75° West). This is not always the Earth's prime meridian (0° W / 0° E), as the central meridian of
Central meridian (planets)
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Gnostic lens. "Evil" as defined by the Gnostics was a far larger, more pervasive presence in human life than the rather tame and "domesticated" Satan of Christianity. As Daugherty writes, "For [Gnostics], evil was simply everything that "is", with the exception of bits of spirit imprisoned here. And what they saw is what we see in the world of "Blood Meridian"." Barcley Owens argues that, while there are undoubtedly Gnostic qualities to the novel, Daugherty's arguments are "ultimately unsuccessful," because Daugherty fails to address the novel's pervasive violence adequately and because he overstates the kid's goodness. Another major theme concerning
Blood Meridian
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a prime meridian for early map makers, and was known as the Ferro Meridian, at the western extremity of the known world. The name comes from the Orchil lichen that grows on the rocky lava slopes in the area, inland from the point is a 238m peak called Orchilla. The isolated locality of the Punta de la Orchilla means that it has been described as “probably Spain's most remote lighthouse”, reaching the site requires a 25 km trip from Sabinosa via a road that is only partly metalled, the end of the road being both unmade, and uneven. Although the
Punta Orchilla lighthouse
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Longitude is a number preceded by a sign character. A plus sign (codice_2) denotes east longitude or the prime meridian, and a minus sign (codice_3) denotes west longitude or 180° meridian (opposite of the prime meridian). Rules about the number of digits are the same as for latitude. The CRS identifier begins with "CRS". There are three styles: The example of original Annex H always use "CRSWGS_84". ISO 6709 ISO 6709 "Standard representation of geographic point location by coordinates" is the international standard for representation of latitude, longitude and altitude for geographic point locations. The first edition (ISO 6709:1983) was
ISO 6709
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90th meridian east The meridian 90° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole. It is the border between two tropical cyclone basins: the Australian region, and the Southwest Indian Ocean basin. The Ninety East Ridge is named after the meridian. The 90th meridian east forms a great circle with the 90th meridian west. This meridian is halfway between the Prime meridian and the 180th meridian and the center of the Eastern Hemisphere is on this meridian.
90th meridian east
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Time effectively became the international standard for time calculation around the world based on the Prime meridian at Greenwich in London. Previously only local time was used, the setting of noon based on the length of the shadow from a gnomon (on a sundial). The Meridian features in the film Pingwin (Penguin) (1965) starring Zbigniew Cybulski. Warsaw meridian The Warsaw meridian () is a meridian line running through Warsaw. The local mean time at the meridian was known as Warsaw Mean Time. It corresponds to an offset from UTC of . In 1880, a small column marking the meridian was
Warsaw meridian
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Longitude Longitude (, ), is a geographic coordinate that specifies the east–west position of a point on the Earth's surface. It is an angular measurement, usually expressed in degrees and denoted by the Greek letter lambda (λ). Meridians (lines running from pole to pole) connect points with the same longitude. By convention, one of these, the Prime Meridian, which passes through the Royal Observatory, Greenwich, England, was allocated the position of 0° longitude. The longitude of other places is measured as the angle east or west from the Prime Meridian, ranging from 0° at the Prime Meridian to +180° eastward
Longitude
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point to a Grid North, varying slightly from True North. This variation is zero on the central meridian (north-south line) of the map, which is at two degrees West of the Prime Meridian, and greatest at the map edges. The difference between grid north and true north is very small and can be ignored for most navigation purposes. The difference exists because the correspondence between a flat map and the round Earth is necessarily imperfect. At the South Pole, grid north conventionally points northwards along the Prime Meridian. Since the meridians converge at the poles, true east and west directions
Grid north
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strip is indeed at "astronomical" longitude zero degrees, zero minutes, and zero seconds—but GPS receivers show "geodetic" longitude, which equalises the higher mass, otherwise seen, of the eastern hemisphere (specifically per Standard ITRF/WGS 84). Before the establishment of a common meridian, most maritime countries established their own prime meridian, usually passing through the country in question. In 1721, Great Britain established its own meridian passing through an early transit circle at the newly established Royal Observatory at Greenwich. The meridian was moved around 10 metres or so east on three occasions as transit circles with newer and better instruments were
Prime meridian (Greenwich)
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kilometres/5.7 miles. Each medallion is 12 cm in diameter and marked with the name ARAGO plus N and S pointers. Another project, the Green Meridian ("An 2000 — La Méridienne Verte"), aims to establish a plantation of trees along the entire length of the meridian arc in France. Several missing Arago medallions appear to have been replaced with the newer 'An 2000 — La Méridienne Verte' markers. In certain circles, some kind of occult or esoteric significance is ascribed to the Paris meridian; sometimes it is even perceived as a sinister axis. Dominique Stezepfandts, a French conspiracy theorist, attacks the
Paris meridian
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two main locations that were acknowledged as the geographic location of the meridian, France and Britain. These two locations often conflicted and a settlement was reached only after there was an International Meridian Conference held, in which Greenwich was recognized as the 0° location. The meridian through Greenwich (inside Greenwich Park), England, called the Prime Meridian, was set at zero degrees of longitude, while other meridians were defined by the angle at the center of the earth between where it and the prime meridian cross the equator. As there are 360 degrees in a circle, the meridian on the opposite
Meridian (geography)
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180th meridian The 180th meridian or antimeridian is the meridian 180° both east and west of the Prime Meridian, with which it forms a great circle dividing the earth into the Western and Eastern Hemispheres. It is common to both east longitude and west longitude. It mostly passes through the open waters of the Pacific Ocean, but passes across land in Russia, Fiji and Antarctica. This meridian is used as the basis for the International Date Line, but the latter deviates from it to maintain date consistency within the territories of Russia, USA, Kiribati, Fiji and New Zealand. Starting at
180th meridian
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a result, the International Reference Meridian was established and is commonly used to denote Earth's prime meridian (0° longitude) by the International Earth Rotation and Reference Systems Service, which defines and maintains the link between longitude and time. Based on observations to satellites and celestial compact radio sources (quasars) from various coordinated stations around the globe, Airy's transit circle drifts northeast about 2.5 centimetres per year relative to this Earth-centred 0° longitude. It is also the reference meridian of the Global Positioning System operated by the United States Department of Defense, and of WGS84 and its two formal versions, the
Prime meridian
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90th meridian west The meridian 90° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, North America, the Gulf of Mexico, Central America, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole. In Antarctica, the meridian defines the western limit of Chile's territorial claim. The land further west is not claimed by any nation. The 90th meridian west forms a great circle with the 90th meridian east, located midway between the Prime meridian and the 180th meridian; thus the center of the Western Hemisphere is on this meridian.
90th meridian west
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of seven seconds per day. British astronomers have long used the Royal Observatory as a basis for measurement. Four separate meridians have passed through the buildings, defined by successive instruments. The basis of longitude, the meridian that passes through the Airy transit circle, first used in 1851, was adopted as the world's Prime Meridian at the International Meridian Conference on 22 October 1884 (voting took place on 13 October). Subsequently, nations across the world used it as their standard for mapping and timekeeping. The Prime Meridian was marked by a brass (later replaced by stainless steel) strip in the Observatory's
Royal Observatory, Greenwich
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at the end of the International Meridian Conference. This location was chosen because by 1884 two-thirds of all nautical charts and maps already used it as their prime meridian. The conference did not adopt Fleming's time zones because they were outside the purpose for which it was called, which was to choose a basis for universal time (as well as a prime meridian). During the period between 1848 and 1972, all of the major countries adopted time zones based on the Greenwich meridian. In 1935, the term "Universal Time" was recommended by the International Astronomical Union as a more precise
Universal Time
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Toft Lions, who play in the CDFL Cambridgeshire men's league. Toft, Cambridgeshire Toft is a village situated in Cambridgeshire, England. It is approximately six miles to the west of Cambridge, and is situated within four miles of the M11 motorway. It has approximately 600 residents and 200 homes. Comberton Village College and Comberton Sixth Form fall within the Toft Parish boundary. The village has two churches, St Andrew's Parish Church and Toft Methodist Church. Just to the west of the village is Cambridge Meridian Golf Club, which has the Prime Meridian running through the 14th fairway. The name "Toft" is
Toft, Cambridgeshire
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Toft, Cambridgeshire Toft is a village situated in Cambridgeshire, England. It is approximately six miles to the west of Cambridge, and is situated within four miles of the M11 motorway. It has approximately 600 residents and 200 homes. Comberton Village College and Comberton Sixth Form fall within the Toft Parish boundary. The village has two churches, St Andrew's Parish Church and Toft Methodist Church. Just to the west of the village is Cambridge Meridian Golf Club, which has the Prime Meridian running through the 14th fairway. The name "Toft" is derived from an old Viking word meaning "curtilage" or "homestead".
Toft, Cambridgeshire
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27th meridian west from Washington The 27th meridian west from Washington is an archaic meridian based on the Washington Meridian. The meridian is approximately 104 degrees west of the Prime Meridian. It is used as the boundary of five states. The usage of the meridian as a boundary began in 1863 when the Idaho Territory was created, with the 27th meridian as its eastern boundary. At that time, the Dakota Territory and the Nebraska Territory gained their western boundary as portions of those territories were made a part of Idaho Territory. Nebraska became a state in 1867. In 1868, the
27th meridian west from Washington
18051102
Wyoming Territory was created with the meridian as its eastern boundary. The Dakota Territory was divided into North and South Dakota on November 2, 1889, and Montana became a state just six days later. Wyoming became a state in 1890. 27th meridian west from Washington The 27th meridian west from Washington is an archaic meridian based on the Washington Meridian. The meridian is approximately 104 degrees west of the Prime Meridian. It is used as the boundary of five states. The usage of the meridian as a boundary began in 1863 when the Idaho Territory was created, with the 27th
27th meridian west from Washington
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the circle was aligned with the local vertical or plumb line, which is deflected slightly from the normal, or line perpendicular, to the reference ellipsoid used to define geodetic latitude and longitude in the International Terrestrial Reference Frame (which is nearly the same as the WGS-84 system used by GPS). While the local vertical defined at the Airy transit circle still points to the modern celestial meridian (the intersection of the prime meridian plane with the celestial sphere), it does not pass through the Earth's rotation axis. As a result of this, the ITRF zero meridian, defined by a plane
Prime meridian (Greenwich)
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passing through the Earth's rotation axis, is 102.478 metres to the east of the prime meridian. A 2015 analysis by Malys et al. shows the offset between the Airy transit circle and the ITRF/WGS 84 meridians can be explained by this deflection of the vertical alone; other possible sources of the offset that have been proposed in the past are smaller than the current uncertainty in the deflection of the vertical near the observatory. The astronomical longitude of the Greenwich prime meridian was found to be 0.19″ ± 0.47″ East, i.e. the plane defined by the local vertical on the
Prime meridian (Greenwich)
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second eccentricity. There are only two independent shape parameters and there are many relations between them: in particular The projection formulae also involve formula_9, the radius of curvature of the meridian (at latitude formula_10), and formula_11, the radius of curvature in the prime vertical. (The prime vertical is the vertical plane orthogonal to the meridian plane at a point on the ellipsoid). The radii of curvature are defined as follows: In addition the functions formula_13 and formula_14 are defined as: For compactness it is normal to introduce the following abbreviations: The article on Meridian arc describes several methods of computing
Transverse Mercator: Redfearn series
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local vertical to using a meridian based on the centre of the Earth caused the modern prime meridian to be 5.3" east of the astronomic Greenwich prime meridian through the Airy Transit Circle. At the latitude of Greenwich, this amounts to 102 metres. This was officially accepted by the Bureau International de l'Heure (BIH) in 1984 via its BTS84 (BIH Terrestrial System) that later became WGS84 (World Geodetic System 1984) and the various ITRFs (International Terrestrial Reference Systems). Due to the movement of Earth's tectonic plates, the line of 0° longitude along the surface of the Earth has slowly moved
Prime meridian
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meridian. The meridian chosen was that which passed through the Airy transit circle at Greenwich and it became the prime meridian. At around the time of this conference, scientists were making measurements to determine the deflection of the vertical on a large scale. One might expect that plumb lines set up in various locations, if extended downward, would all pass through a single point, the centre of the Earth, but this is not the case, primarily due to the Earth being an ellipsoid, not a sphere. The downward extended plumb lines don't even all intersect the rotation axis of the
Prime meridian (Greenwich)
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a succession of earlier transit instruments, the first of which was acquired by the second Astronomer Royal, Edmond Halley in 1721. It was set up in the extreme north-west corner of the Observatory between Flamsteed House and the Western Summer House. This spot, now subsumed into Flamsteed House, is roughly 43 metres to the west of the Airy Transit Circle, a distance equivalent to roughly 0.15 seconds of time. It was Airy's transit circle that was adopted in principle (with French delegates, who pressed for adoption of the Paris meridian abstaining) as the Prime Meridian of the world at the
Prime meridian
6111930
the "Europäische Gradmessung" proposed to select the Greenwich meridian as the prime meridian in the hope that Great Britain would accede to the Metre Convention. The United States passed an Act of Congress on 3 August 1882 authorizing the President to call an international conference to fix on a common prime meridian for time and longitude throughout the world. Before the invitations were sent out on December 1, the joint efforts of Abbe, Fleming and William Frederick Allen, Secretary of the US railways' "General Time Convention" and Managing Editor of the "Travellers' Official Guide to the Railways", had brought the
Paris meridian
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and earlier photographs. The Mariner 9 Geodesy/Cartography Group proposed that the prime meridian of Mars be defined by the center of Airy-0, which was selected by Harold Masursky, Gerard de Vaucouleurs, and Merton Davies at a Group meeting on 14 August 1972. It was named in honor of the British Astronomer Royal Sir George Biddell Airy (1801-1892), who in 1850 built the transit circle telescope at Greenwich. The location of that telescope was subsequently chosen to define the location of Earth's prime meridian. Airy-0 Airy-0 is a crater on Mars whose location defined the position of the prime meridian of
Airy-0
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"a", "b" and "f". They are listed in ellipse. A primary use of reference ellipsoids is to serve as a basis for a coordinate system of latitude (north/south), longitude (east/west), and ellipsoidal height. For this purpose it is necessary to identify a "zero meridian", which for Earth is usually the Prime Meridian. For other bodies a fixed surface feature is usually referenced, which for Mars is the meridian passing through the crater Airy-0. It is possible for many different coordinate systems to be defined upon the same reference ellipsoid. The longitude measures the rotational angle between the zero meridian and
Reference ellipsoid
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introduced at noon on November 18, 1883, when the telegraph lines transmitted time signals to all major cities. In October 1884, the International Meridian Conference at Washington DC adopted a proposal which stated that the prime meridian for longitude and timekeeping should be one that passes through the centre of the transit instrument at the Greenwich Observatory in the United Kingdom (UK). The conference therefore established the Greenwich Meridian as the prime meridian and Greenwich Mean Time (GMT) as the world's time standard. The US time-zone system grew from this, in which all zones referred back to GMT on the
Time in the United States
604687
a consistent meridian for a world map in his "Geographia". Ptolemy used as his basis the "Fortunate Isles", a group of islands in the Atlantic which are usually associated with the Canary Islands (13° to 18°W), although his maps correspond more closely to the Cape Verde islands (22° to 25° W). The main point is to be comfortably west of the western tip of Africa (17.5° W) as negative numbers were not yet in use. His prime meridian corresponds to 18° 40' west of Winchester (about 20°W) today. At that time the chief method of determining longitude was by using
Prime meridian
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Florence Meridian. It passes through: Florence meridian The Meridian 11°15' East was proposed as prime meridian by Arno Peters in the Peters World Map. The Meridian is the antipode of 168°45' West of Greenwich which runs through the Bering Strait and was proposed as a new date line. On Peters' world map the easternmost part of Asia and Russia is not displayed left of Alaska, as is usually done on Greenwich-centered maps, but on the right side as the rest of Russia and Asia. The meridian, 11° 15' East of Greenwich traverses the city center of Florence in Italy and
Florence meridian
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regions, directions can become complicated, with all geographic north–south lines converging at the poles. The difference between UPS grid north and true north can therefore be anything up to 180°—in some places, grid north is true south, and vice versa. UPS grid north is arbitrarily defined as being along the prime meridian in the Antarctic and the 180th meridian in the Arctic; thus, east and west on the grids when moving directly away from the pole are along the 90°E and 90°W meridians respectively. As the name indicates, the UPS system uses a stereographic projection. Specifically, the projection used in
Universal polar stereographic coordinate system
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Meridian (geography) A (geographical) meridian (or line of longitude) is the half of an imaginary great circle on the Earth's surface, terminated by the North Pole and the South Pole, connecting points of equal longitude, as measured in angular degrees east or west of the Prime Meridian. The position of a point along the meridian is given by that longitude and its latitude, measured in angular degrees north or south of the Equator. Each meridian is perpendicular to all circles of latitude. Each is also the same length, being half of a great circle on the Earth's surface and therefore
Meridian (geography)
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west side of L'Enfant's triangle forms a natural prime meridian passing through the President's house. The following nine features on and near this "Washington Meridian" are listed from south to north: The third meridian was defined on September 28, 1850 by Congress: "[T]he meridian of the observatory at Washington shall be adopted and used as the American meridian for all astronomical purposes and ... the meridian of Greenwich shall be adopted for all nautical purposes." The observatory decided that this meridian passed through the center of the original (small) dome atop the main building of the "Old Naval Observatory", now
Washington meridians
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and −180° westward. Specifically, it is the angle between a plane through the Prime Meridian and a plane through both poles and the location in question. (This forms a right-handed coordinate system with the -axis (right hand thumb) pointing from the Earth's center toward the North Pole and the -axis (right hand index finger) extending from the Earth's center through the Equator at the Prime Meridian.) A location's north–south position along a meridian is given by its latitude, which is approximately the angle between the local vertical and the equatorial plane. If the Earth were perfectly spherical and radially homogeneous,
Longitude
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of Cambridge, and just half a mile (800 m) east of the Prime Meridian, lying at a modest elevation of around 25 feet (8 m) above sea level. The civil parish covers , and is part of the local government district of South Cambridgeshire. Nearby villages include Barton to the east and Toft to the west. Comberton is twinned with Le Vaudreuil, a village near Rouen, France. The Prime Meridian is marked by a Meridian Line stone plaque on the north side of the main road (B1046) between Comberton and the neighbouring village of Toft. The line runs up the
Comberton
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prime meridian line. The current line is one of many that have existed, however the Global Positioning Satellite (GPS) system uses a prime meridian that is about 100 metres east of the Greenwich Meridian at Stanstead Abbotts. The village is served by St Margarets station on the Hertford East Line, operated by Abellio Greater Anglia. St Margaret's Station was formerly the start of the now disused Buntingford Branch Line. The St. Margaretsbury recreation ground hosts both a football club, St. Margaretsbury F.C., and both youth and adult and cricket club. The village has a Scout Group, the 1st Stanstead Abbotts
Stanstead St Margarets
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Albrecht was used prior to the switch to the Greenwich prime meridian. The island of El Hierro spans more than a quarter of a degree of longitude, from Ensenada de Juanil at 17.8829°W, to Roque del Guincho at 18.1612°W. Ferro Meridian The line of longitude running through El Hierro (Ferro), the westernmost of the Canary Islands, was known in European history as the prime meridian in common use outside of the future British Empire. Already in the 2nd century A.D., Ptolemy considered a definition of the zero meridian based on the western-most position of the known world, giving maps with
Ferro Meridian
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built, on each occasion next door to the existing one. This was to allow uninterrupted observation during each new construction. The final meridian was established as an imaginary line from the north pole to the south pole passing through the Airy transit circle. This became Great Britain's meridian in 1851. For all practical purposes of the period, the changes as the meridian was moved went unnoticed. Transit instruments are installed to be perpendicular to the local level (which is a plane perpendicular to a plumb line). In 1884, the International Meridian Conference took place to establish an internationally recognised single
Prime meridian (Greenwich)
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the East Boston Lumber Company. During this period, the Boston Sugar Refinery was also founded, which was the first manufacturing establishment in East Boston. They are credited for the creation of white granulated sugar. The Kennedy Family lived on Meridian Street in what is now a small home wedged between a Hispanic market and hardware store, approaching the Meridian Street branch of the Boston Public Library. The family later moved to a larger home on Monmouth Street. P. J. Kennedy's success enabled him to purchase a home for his son, Joseph, and another for his two daughters at Jeffries Point.
East Boston
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Null Island Null Island is a name for the area around the point where the prime meridian and the equator cross; in the WGS84 datum, this is at zero degrees latitude and longitude [.] (the location is in the Gulf of Guinea off the west African coast). The name 'Null Island' serves as both a joke based around the suppositional existence of an island there (in reality, only a buoy [pictured] exists there), and also as a name to which coordinates erroneously set to 0,0 are assigned in placenames databases in order to more easily find and fix them. The
Null Island
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Florence meridian The Meridian 11°15' East was proposed as prime meridian by Arno Peters in the Peters World Map. The Meridian is the antipode of 168°45' West of Greenwich which runs through the Bering Strait and was proposed as a new date line. On Peters' world map the easternmost part of Asia and Russia is not displayed left of Alaska, as is usually done on Greenwich-centered maps, but on the right side as the rest of Russia and Asia. The meridian, 11° 15' East of Greenwich traverses the city center of Florence in Italy and therefore is also known as
Florence meridian
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Tallahassee meridian The Tallahassee meridian, in longitude 84° 16′ 37.59″ west from the prime meridian at Greenwich, runs north and south from the initial point on the base line at Tallahassee, in latitude 30° 26′ 04.12″ north, and as a principal meridian governs the surveys in Florida and Alabama as part of the Public Land Survey System. The term "Tallahassee meridian" is also loosely used to describe the survey monument (see survey marker) located at the intersection of these lines of longitude and latitude (the longitude line being the "Tallahassee meridian" and the latitude line being the "Tallahassee Parallel" or
Tallahassee meridian
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longitude and latitude of the earth. These instruments also were typically effected by local gravity, which paired well with existing technologies such as the magnetic meridian. Tools of Measurement Meridian (geography) A (geographical) meridian (or line of longitude) is the half of an imaginary great circle on the Earth's surface, terminated by the North Pole and the South Pole, connecting points of equal longitude, as measured in angular degrees east or west of the Prime Meridian. The position of a point along the meridian is given by that longitude and its latitude, measured in angular degrees north or south of
Meridian (geography)
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meridian meant that there was inconsistency, because each country had their own guidelines for where the prime meridian was located. The term "meridian" comes from the Latin "meridies", meaning "midday"; the subsolar point passes through a given meridian at solar noon, midway between the times of sunrise and sunset on that meridian. Likewise, the Sun crosses the celestial meridian at the same time. The same Latin stem gives rise to the terms a.m. (ante meridiem) and p.m. (post meridiem) used to disambiguate hours of the day when utilizing the 12-hour clock. Toward the ending of the 19th century there were
Meridian (geography)
9519676
32nd meridian west from Washington The 32nd meridian of longitude west from Washington is a line of longitude approximately 109°02′48″ west of the Prime Meridian of Greenwich. In the United States of America, the meridian 32 degrees west of the Washington Meridian defines the western boundaries of the State of Colorado and the State of New Mexico and the eastern boundaries of the State of Utah and the State of Arizona. On February 28, 1861, the Act Organizing the Territory of Colorado defined the western boundary of the new territory as the 32nd meridian of longitude west from Washington. The
32nd meridian west from Washington
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mariners but he admitted to his friend and biographer, Walter Ghym, that the map lacked a sufficiently clear detailed explanation of its use. The intention expressed in the last sentence of Legend 10, that he would give more information in a future 'Geographia', was never realized. In Legend 5 Mercator argues that the Prime Meridian should be identified with that on which the magnetic declination is zero, namely the meridian through the Cape Verde islands, or alternatively that through the island of Corvo in the Azores. (He cites the varying opinions of the Dieppe mariners). The prime meridian is labelled
Mercator 1569 world map
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are Maxwell Montes, named after James Clerk Maxwell, and highland regions Alpha Regio, Beta Regio, and Ovda Regio. The latter three features were named before the current system was adopted by the International Astronomical Union, the body which oversees planetary nomenclature. The longitudes of physical features on Venus are expressed relative to its prime meridian. The original prime meridian passed through the radar-bright spot at the centre of the oval feature Eve, located south of Alpha Regio. After the Venera missions were completed, the prime meridian was redefined to pass through the central peak in the crater Ariadne. Much of
Venus
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to the previous one (to maintain the service to shipping). Such changes had no significant practical effect. Historically, the average error in the determination of longitude was much larger than the change in position. The adoption of WGS84 ("World Geodetic System 84") as the positioning system has moved the geodetic prime meridian 102.478 metres east of its last astronomic position (measured at Greenwich). The position of the current geodetic prime meridian is not identified at all by any kind of sign or marking (as the older astronomic position was) in Greenwich, but can be located using a GPS receiver. It
Meridian (geography)
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daylight saving time is used, that time is defined by another offset, from the standard time in its applicable time zones. The adoption of standard time, because of the inseparable correspondence between time and longitude, solidified the concepts of halving the globe into an eastern and western hemisphere, with one prime meridian (as well its opposite International Date Line) replacing the various prime meridians that had previously been used. During the 19th century, scheduled steamships and trains required time standardization in the industrialized world. A standardized time system was first used by British railways on December 1, 1847, when they
Standard time
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observation buoy, part of the PIRATA system operated jointly by the United States, France, and Brazil. The depth at this place is around . Null Island Null Island is a name for the area around the point where the prime meridian and the equator cross; in the WGS84 datum, this is at zero degrees latitude and longitude [.] (the location is in the Gulf of Guinea off the west African coast). The name 'Null Island' serves as both a joke based around the suppositional existence of an island there (in reality, only a buoy [pictured] exists there), and also as
Null Island
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international. 25th meridian west from Washington The 25th meridian of longitude west from Washington is a line of longitude approximately 102.05 degrees west of the Prime Meridian of Greenwich. In the United States of America, the meridian 25 degrees west of the Washington Meridian defines the eastern boundary of the State of Colorado, the western boundary of the State of Kansas, and the western boundary of the State of Nebraska south of the 41st parallel north. On January 1, 1861, the Act Admitting the State of Kansas to the Union defined the western boundary of the new state as the
25th meridian west from Washington
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25th meridian west from Washington The 25th meridian of longitude west from Washington is a line of longitude approximately 102.05 degrees west of the Prime Meridian of Greenwich. In the United States of America, the meridian 25 degrees west of the Washington Meridian defines the eastern boundary of the State of Colorado, the western boundary of the State of Kansas, and the western boundary of the State of Nebraska south of the 41st parallel north. On January 1, 1861, the Act Admitting the State of Kansas to the Union defined the western boundary of the new state as the 25th
25th meridian west from Washington
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the planet. Mars' equator is defined by its rotation, but the location of its prime meridian was specified, as was Earth's, by choice of an arbitrary point which was accepted by later observers. The German astronomers Wilhelm Beer and Johann Heinrich Mädler selected a small circular feature in the Sinus Meridiani ('Middle Bay' or 'Meridian Bay') as a reference point when they produced the first systematic chart of Mars features in 1830–32. In 1877, their choice was adopted as the prime meridian by the Italian astronomer Giovanni Schiaparelli when he began work on his notable maps of Mars. In 1909
Geography of Mars
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the Prime Meridian, on which all Coordinated Universal Time is based. The Prime Meridian running through Greenwich and the Greenwich Observatory is where the designation Greenwich Mean Time, or GMT began, and on which all world times are based. In 2012, Greenwich was listed as a top ten global destination by Frommer's – the only UK destination to be listed. Greenwich was one of six host boroughs for the 2012 London Olympics and events were held at the Royal Artillery Barracks (shooting), Greenwich Park (equestrianism) and The O – the former Millennium Dome (gymnastics and basketball). It is also the
Royal Borough of Greenwich