HM Nautical Almanac Office (HMNAO) is part of the UK Hydrographic Office based at Taunton in Somerset.
These web pages describe the publications and services of HM Nautical Almanac Office. A description of the type of work we carry out and the history of the office is also available.
The Office produces astronomical data suitable for a wide range of users, including professional and amateur astronomers, mariners, aviators, surveyors, the Armed Forces, the Police, lawyers, religious groups, architects, schools, diary and calendar manufacturers, photographers and film crews. In fact, anyone requiring astronomical information may have need of our services.
HMNAO is jointly responsible for producing the annual volumes of The Astronomical Almanac, The Nautical Almanac and Astronomical Phenomena in collaboration with our colleagues at the US Nautical Almanac Office within the Astronomical Applications Department of the US Naval Observatory. HMNAO also produces The Star Almanac, NavPac and Compact Data, The UK Air Almanac, Rapid Sight Reduction Tables for Navigation and Planetary and Lunar Coordinates published in the United Kingdom.