Greenwich

Coordinates: 51°29′N 0°00′E / 51.48°N 0.00°E / 51.48; 0.00

Greenwich (ⁱ/ˈɡrɛnɪtʃ/, /ˈɡrɪnɪdʒ/, /ˈɡrɪnɪtʃ/ or /ˈɡrɛnɪdʒ/) is an early-established district of today's London, England, centred 5.5 miles (8.9 km) east south-east of Charing Cross. The town lends its name to the Royal Borough of Greenwich.

Greenwich is generally described as being part of South-east London and sometimes as being part of East London. It is also one of the five boroughs of the London Docklands, connected to areas with docks of London historically by river and today to Canary Wharf and other buildings by the East London Line.

Greenwich is notable for its maritime history and for giving its name to the Greenwich Meridian (0° longitude) and Greenwich Mean Time. The town became the site of a royal palace, the Palace of Placentia from the 15th century, and was the birthplace of many Tudors, including Henry VIII and Elizabeth I. The palace fell into disrepair during the English Civil War and was rebuilt as the Royal Naval Hospital for Sailors by Sir Christopher Wren and his assistant Nicholas Hawksmoor. These buildings became the Royal Naval College in 1873, and they remained an establishment for military education until 1998 when they passed into the hands of the Greenwich Foundation. The historic rooms within these buildings remain open to the public; other buildings are used by University of Greenwich and Trinity Laban Conservatoire of Music and Dance.

Royal Observatory

Royal Observatory may refer to:

London

London ⁱ/ˈlʌndən/ is the capital and most populous city of England and the United Kingdom. Standing on the River Thames, London has been a major settlement for two millennia. It was founded by the Romans, who named it Londinium. London's ancient core, the City of London, largely retains its 1.12-square-mile (2.9 km²) medieval boundaries and in 2011 had a resident population of 7,375, making it the smallest city in England. Since at least the 19th century, the term London has also referred to the metropolis developed around this core. The bulk of this conurbation forms Greater London, a region of England governed by the Mayor of London and the London Assembly. The conurbation also covers two English counties: the small district of the City of London and the county of Greater London. The latter constitutes the vast majority of London, though historically it was split between Middlesex (a now abolished county), Essex, Surrey, Kent and Hertfordshire.

Greenwich Park

Greenwich Park is a former hunting park in Greenwich and one of the largest single green spaces in south-east London. One of the Royal Parks of London, and the first to be enclosed (in 1433), it covers 74 hectares (180 acres), and is part of the Greenwich World Heritage Site. It commands fine views over the River Thames, the Isle of Dogs and the City of London. The park is open from 06:00 for pedestrians (and 07:00 for traffic) all year round and closes at dusk.

History

The estate of some 200 acres (81 ha) was originally owned by the Abbey of St. Peter at Ghent, but reverted to the Crown in 1427 and was given by Henry VI to his uncle Humphrey, Duke of Gloucester. He built a house by the river, Bella Court, and a small castle, called Greenwich Castle as well as Duke Humphrey’s Tower, on the hill. The former evolved first into the Tudor Palace of Placentia and then into the Queen's House and Greenwich Hospital. Greenwich Castle, by now in disrepair, was chosen for the site of the Royal Observatory by Charles II in 1675.

Greenwich Mean Time

Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London. GMT was formerly used as the international civil time standard, now superseded in that function by Coordinated Universal Time (UTC). Today GMT is considered equivalent to UTC for UK civil purposes (but this is not formalized) and for navigation is considered equivalent to UT1 (the modern form of mean solar time at 0° longitude); these two meanings can differ by up to 0.9 s. Consequently, the term GMT should not be used for precise purposes.

Because of Earth's uneven speed in its elliptical orbit and its axial tilt, noon (12:00:00) GMT is rarely the exact moment the sun crosses the Greenwich meridian and reaches its highest point in the sky there. This event may occur up to 16 minutes before or after noon GMT, a discrepancy calculated by the equation of time. Noon GMT is the annual average (i.e., "mean") moment of this event, which accounts for the word "mean" in "Greenwich Mean Time".