HM Nautical Almanac Office

Her Majesty's Nautical Almanac Office (HMNAO), now part of the United Kingdom Hydrographic Office, was established in 1832 on the site of the Royal Greenwich Observatory (RGO), where the Nautical Almanac had been published since 1767. HMNAO produces astronomical data for a wide range of users, such as astronomers, mariners, aviators, surveyors, the military, Police, lawyers, religious groups, architects, schools, diary and calendar manufacturers, photographers and film crews.