Royal Observatory, Greenwich

Royal Observatory, Greenwich. Notice the time ball atop the Octagon Room.

The Royal Observatory, Greenwich (Royal Greenwich Observatory or 'RGO') was commissioned in 1675 by King Charles II.

At this time the king also created the position of Astronomer Royal, for John Flamsteed, to beas the director of the observatory.

He was 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".

The Observatory is on a hill in Greenwich Park in Greenwich, London, overlooking the River Thames.

The Greenwich Meridian runs through the site of the Observatory. It is the line at which the longitude is defined as 0°.

Other websites

• HM Nautical Almanac Office Archived 2007-06-30 at the Wayback Machine
• The Royal Observatory, Greenwich Archived 1999-04-20 at the Wayback Machine
• Aerial View of The Royal Observatory, Greenwich at Google Maps
• The National Maritime Museum Archived 2011-12-12 at the Wayback Machine
• The RGO at Herstmonceux Archived 2008-12-05 at the Wayback Machine
• The Observatory Science Centre
• Isaac Newton Group of Telescopes Archived 2015-07-29 at the Wayback Machine