The Royal Observatory was founded in 1675. The astronomers left Greenwich during the 1950s because London light and air pollution was affecting observations. Under the new title 'Royal Greenwich Observatory', or RGO, they moved first to Herstmonceux Castle in Sussex and then in 1990 to Cambridge.
During its 323 years work the RGO naturally accumulated a large number of historic objects. With its closure these came back home to the Observatory buildings at Greenwich, which became part of the National Maritime Museum in the 1950s. This display has been put together to give a glimpse of the contents of this important collection, and why the astronomers at Herstmonceux and Cambridge decided to keep what they did.
Some objects were kept because of their associations with the Observatory's great history. These celebrate the importance of the institution and its associations.
The astronomers working at the RGO in the 20th century kept some historic instruments for their continuing usefulness. Some remained as they were, others were adapted for new uses or to incorporate new technology.
The Observatory played an important role in maintaining standards of measurement. Maintaining and distributing Greenwich Mean Time to the nation is the most obvious example, but the Observatory was also one of the repositories for standard length and weight measures in Britain in the 19th century.
Although the Observatory was originally founded to help improve navigation at sea, the late 19th century saw its work move away from its maritime roots. This is evident in some of the instruments but others show that an interest in navigational technology remained.