Her Majesty's Nautical Almanac Office

Her Majesty's Nautical Almanac Office (HMNAO) is the UK agency responsible for producing precise astronomical data used for navigation and astronomy. It provides charts and published tables that allow mariners, pilots, and astronomers to determine their position at sea or on land by observing celestial bodies like the Sun, Moon, and stars. The data ensures accurate navigation, safety, and scientific research. HMNAO collaborates internationally and supports maritime, aviation, and scientific communities by maintaining up-to-date, reliable astronomical information essential for precise positioning and timekeeping.