A nautical almanac is a publication describing the positions and movements of celestial bodies, including the sun, moon, planets, and stars. In Great Britain a nautical almanac has been published annually by the HM Nautical Almanac Office, ever since the first edition was published in 1767. The nautical almanac is usually used together with a sextant and a chronometer for celestial navigation while at sea.

See also

• celestial navigation
• navigation

External links and resources

• Her Majesty's Nautical Almanac Office
• The History of HM Nautical Almanac Office