1833 Daily time signals began, marked by dropping a time ball.1818 Oversight of the Royal Observatory was transferred from the Board of Ordnance to the Board of Admiralty at that time the observatory was charged with maintaining the Royal Navy's marine chronometers.1767 The fifth Astronomer Royal Nevil Maskelyne began publication of The Nautical Almanac, based on observations made at the Observatory.The Astronomer Royal was, until the Board was dissolved in 1828, always an ex officio Commissioner of Longitude. 1714 Longitude Act established the Board of Longitude and Longitude rewards.1675 – 22 June, Royal Observatory founded by King Charles II.( November 2019) ( Learn how and when to remove this template message) Unsourced material may be challenged and removed. Please help improve this article by adding citations to reliable sources. This section needs additional citations for verification. The scientific work of the observatory was relocated elsewhere in stages in the first half of the 20th century, and the Greenwich site is now maintained almost exclusively as a museum, although the AMAT telescope became operational for astronomical research in 2018. The building was often called "Flamsteed House", in reference to its first occupant. The building was completed in the summer of 1676. At that time the king also created the position of Astronomer Royal, 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 longitude of places for the perfecting of the art of navigation." He appointed John Flamsteed as the first Astronomer Royal. The old hilltop site of Greenwich Castle was chosen by Sir Christopher Wren, a former Savilian Professor of Astronomy as Greenwich Park was a royal estate, no new land needed to be bought. The observatory was commissioned in 1675 by King Charles II, with the foundation stone being laid on 10 August. ROG, the National Maritime Museum, the Queen's House and the clipper ship Cutty Sark are collectively designated Royal Museums Greenwich.
The ROG has the IAU observatory code of 000, the first in the list.
It played a major role in the history of astronomy and navigation, and because the Prime Meridian passes through it, it gave its name to Greenwich Mean Time, the precursor to today's Coordinated Universal Time (UTC). The Royal Observatory, Greenwich ( ROG known as the Old Royal Observatory from 1957 to 1998, when the working Royal Greenwich Observatory, RGO, temporarily moved south from Greenwich to Herstmonceux) is an observatory situated on a hill in Greenwich Park in south east London, overlooking the River Thames to the north.