Royal Greenwich Observatory

The original site of the Royal Greenwich Observatory (RGO), which was built as a workplace for the Astronomer Royal, was on a hill in Greenwich Park in Greenwich, London, overlooking the River Thames. The Prime Meridian, to which longitude refers, went through the observatory. It is marked by a brass strip in the courtyard and, since December 16, 1999, a powerful green laser shining north across the London night sky.

External links

• HM Nautical Almanac Office
• The Royal Observatory, Greenwich
• The National Maritime Museum
• The RGO at Herstmonceux
• The Observatory Science Centre
• Isaac Newton Group of Telescopes