- Royal Observatory, Greenwich
The Royal Observatory, Greenwich (formerly the Royal Greenwich Observatory or RGO) was commissioned in
1675by King Charles II, with the foundation stonebeing laid on 10 August. [ [http://www.thehistorychannel.co.uk/site/this_day_in_history/this_day_August_10.php The History Channel: This day in history] ] At this time the king also created the position of Astronomer Royal(initially filled by John Flamsteed), to serve as the director of the observatory and to "apply himself with the most exact care and diligence to the rectifying of the tables of the motions of the heavens, and the places of the fixed stars, so as to find out the so much desired longitudeof places for the perfecting of the art of navigation." It is situated on a hill in Greenwich Parkin Greenwich, London, overlooking the River Thames.
Flamsteed House, the original part of the Observatory, was designed by Sir
Christopher Wrenprobably with the assistance of Robert Hookeand was the first purpose-built scientific research facility in Britain. It was built for a cost of £520 (£20 over budget) out of largely recycled materials on the foundations of Duke Humphrey's Tower, which resulted in the alignment being 13 degrees away from true North, somewhat to Flamsteed's chagrin.
It housed not only the scientific instruments to be used by Flamsteed in his work on stellar tables, but over time also incorporated a number of additional responsibilities such as the keeping of
timeand later Her Majesty's Nautical Almanac Office.
Two clocks, built by
Thomas Tompion, were installed in the 20 foot high Octagon Room, the principal room of the building. They were of unusual design, each with a pendulum 13 feet (3.96 metres) in length mounted above the clock face, giving a period of four seconds and an accuracy, then unparalleled, of seven seconds per day.
British astronomers have long used the Royal Observatory as a basis for measurement: four separate meridians have been drawn through the building. The basis of
longitude, the Prime Meridian, established in 1851 and adopted at an international conference in 1884, passes through the Airy transit circle of the observatory. It was long marked by a brass strip in the courtyard, now upgraded to stainless steel, and, since 16 December, 1999, has been marked by a powerful green lasershining north across the London night sky.
This old astronomical prime meridian has been replaced by a more modern prime meridian. When Greenwich was an active observatory, geographical coordinates were referred to a local
oblate spheroidcalled a datum, whose surface closely matched local mean sea level, called the geoid. Several datums were in use around the world, all using different spheroids, because mean sea level undulates by as much as 100 metres world-wide. Modern geodetic reference systems, such as the World Geodetic Systemand the International Terrestrial Reference Frame, use a single Earth-centered oblate spheroid. The shift from several spheroids to one world-wide spheroid caused all geographical coordinates to shift by many metres, sometimes as much as several hundred metres. The Prime Meridian of these modern reference systems is 102.5 metres east of the Greenwich astronomical meridian represented by the stainless steel strip. Thus the strip is now 5.31 arcseconds West. Greenwich Mean Time(GMT) was at one time based on the time observations made at Greenwich (until 1954). Thereafter, GMT was calculated from observations made at other observatories which were still active. GMT is now often called Universal Time, which is now calculated from observations of extra-galactic radio sources, and then converted into several forms, including UT0 (UT at the remote observatory), UT1 (UT corrected for polar motion), and UTC (UT in discrete SI seconds within 0.9 s of UT1). To help others synchronize their clocks to GMT, a time ballwas installed by Astronomer Royal John Pondin 1833. It still drops daily to mark the exact moment of 1 p.m. (13:00) year round (GMT during winter and BST during summer). [ [http://wwp.greenwichmeantime.com/info/timeball.htm Greenwich time ball] ]
Bomb attack of 1894
The Observatory underwent an attempted bombing in 1894. This was possibly the first 'international terrorist' incident in Britain. The bomb was detonated by a 26-year-old French
anarchistnamed Martial Bourdin. It is not known why he chose the observatory, or whether the detonation was intended to occur elsewhere. The incident was used as inspiration by Joseph Conradin his novel " The Secret Agent". [ [http://www.nmm.ac.uk/server/show/conWebDoc.413 Propaganda by Deed - the Greenwich Observatory Bomb of 1894] ]
Today the buildings include a museum of astronomical and navigational tools, which is part of the
National Maritime Museum, notably including John Harrison's prize-winning longitude marine chronometer, H4 and its three predecessors. Several additional horological artifacts are also displayed, documenting the history of precision timekeeping for navigational and astronomical purposes, including the mid 20th century Russian-made Fedchenkoclock (the most accurate pendulum clock ever built in multiple copies). It is also home to the 28-inch Grubb refracting telescopeof 1893, the largest of its kind in the UK. The Shepherd Clock outside the observatory gate is an early example of an electric slave clock. In February 2005 construction work began on a £15 million redevelopment project to provide a new planetariumand additional display galleries and educational facilities. The 120 seat Peter Harrison Planetariumofficially opened on May 25, 2007. [ [http://www.nmm.ac.uk/server/show/ConWebDoc.21720 Reopening of the new Royal Observatory, Greenwich] ]
Royal Observatory, Greenwich vs. Royal Greenwich Observatory
During much of the twentieth century, the Royal Greenwich Observatory was not at Greenwich. The last time that all departments were there was 1924: in that year electrification of the railways affected the readings of the Magnetic and Meteorological Department and forced its move to Abinger. In 1939, during
World War II, many departments were evacuated, along with the rest of London, to the countryside (Abinger, Bradford, and Bath) and activities in Greenwich were reduced to the bare minimum.
After the War, in 1947, the decision was made to move to
Herstmonceux Castleand 320 adjacent acres (1.3 km²), 70 km south-southeast of Greenwich near Hailshamin East Sussex, due to light pollutionin London. Although the Astronomer Royal Harold Spencer Jones moved to the castle in 1948, the scientific staff could not move until the completion of new observatory buildings in 1957. Shortly thereafter, other far flung departments were reintegrated at Herstmonceux.
Isaac Newton Telescopewas built at Herstmonceux in 1967, but was moved to Roque de los Muchachos Observatoryin Spain's Canary Islandsin 1979. In 1990 the RGO moved again, to Cambridge. Following a decision of the Particle Physics and Astronomy Research Council, it closed in 1998. Her Majesty's Nautical Almanac Officewas transferred to the Rutherford Appleton Laboratoryafter the closure. Other work went to the UK Astronomy Technology Centrein Edinburgh. The castle grounds are now the home of the International Study Centre of Queen's University, Kingston, Canada and the Observatory Science Centre.
*1675 Royal Observatory, Greenwich founded.
Board of Longitude, Longitude prize
*1924 Hourly time signals (
Greenwich Time Signal) from the Royal Observatory, Greenwich were first broadcast on February 5.
*1948 Astronomer Royal moves to Herstmonceux.
*1957 Royal Observatory completes its move to Herstmonceux, becoming the Royal Greenwich Observatory (RGO). The Greenwich site becomes the Old Royal Observatory.
*1990 RGO moves to Cambridge.
*1998 RGO closes. Greenwich site becomes the Royal Observatory, Greenwich again, and is part of the
National Maritime Museum.
*"Greenwich Observatory: ... the Royal Observatory at Greenwich and Herstmonceux, 1675-1975". London: Taylor & Francis, 1975 3v. (Vol. 1. "Origins and early history (1675-1835)", by Eric G. Forbes. ISBN 0-85066-093-9; Vol. 2. "Recent history (1836-1975)", by A.J. Meadows. ISBN 0-85066-094-7; Vol. 3. "The buildings and instruments" by Derek Howse. ISBN 0-85066-095-5).
* "Greenwich Time and the Longitude". London: Philip Wilson, 1997, by Derek Howse. ISBN 0-85667-468-0.
* [http://www.nao.rl.ac.uk/ HM Nautical Almanac Office]
* [http://www.rog.nmm.ac.uk/ The Royal Observatory, Greenwich]
* [http://maps.google.co.uk/maps?f=q&hl=en&q=Greenwich&ie=UTF8&t=k&om=1&z=19&ll=51.477815,-0.001556&spn=0.00073,0.002438&iwloc=A Aerial View of The Royal Observatory, Greenwich at Google Maps]
* [http://www.nmm.ac.uk/ The National Maritime Museum]
* [http://www.cowbeech.force9.co.uk/RGO.htm The RGO at Herstmonceux]
* [http://www.the-observatory.org/ The Observatory Science Centre]
* [http://www.ing.iac.es Isaac Newton Group of Telescopes]
Wikimedia Foundation. 2010.
Look at other dictionaries:
Royal Observatory — may refer to:* The Royal Observatory, Greenwich (formerly the Royal Greenwich Observatory ) * The Royal Observatory, Edinburgh * Before 1997, Hong Kong Observatory * The Royal Observatory of Belgium, Uccle * Royal Observatory, Cape of Good Hope,… … Wikipedia
Royal Observatory — (also the Royal Greenwich Observatory) an observatory (= a building from which to study the stars, weather, etc.) at Greenwich, London, England. Its original purpose was to study the stars in order to help sailors find their position at sea, and… … Universalium
Observatoire royal de Greenwich — 51°28′40.06″N 0°0′4.96″O / 51.4777944, 0.0013778 … Wikipédia en Français
Observatoire royal de greenwich — Vue sur l Observatoire … Wikipédia en Français
(the) Royal Observatory — the Royal Observatory [the Royal Observatory] (also the Royal Greenwich Observatory) an ↑observatory (= a building from which to study the stars, weather, etc.) at ↑ … Useful english dictionary
Royal Greenwich Observatory — Das Royal Greenwich Observatory (RGO, deutsch Königliches Observatorium von Greenwich), das als Arbeitsplatz für die königlichen Hofastronomen erbaut wurde, lag ursprünglich auf einem Hügel im Greenwich Park in Greenwich, London, von wo aus man… … Deutsch Wikipedia
Greenwich-Observatorium — Royal Greenwich Observatory Das Royal Greenwich Observatory (RGO, zu deutsch Königliches Observatorium von Greenwich), welches als Arbeitsplatz für die königlichen Hofastronomen erbaut wurde, lag ursprünglich auf einem Hügel im Greenwich Park in… … Deutsch Wikipedia
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 convert|183|acre|km2|1 and is part of the Greenwich World… … Wikipedia
Greenwich Mean Time — (GMT) is a term originally referring to mean solar time at the Royal Observatory in Greenwich, London. It is now often used to refer to Coordinated Universal Time (UTC) when this is viewed as a time zone, although strictly UTC is an atomic time… … Wikipedia
Greenwich — This article is about Greenwich in England. For other uses, see Greenwich (disambiguation). Coordinates: 51°28′45″N 0°00′00″E / 51.4791°N 0.0000°E … Wikipedia