The Nautical Almanac

The Nautical Almanac is a reference compendium used by navigators to determine their position at sea. It provides precise information on the positions of celestial bodies—such as the Sun, Moon, planets, and stars—at specific times throughout the year. By measuring angles between these celestial objects and using the Almanac's data, navigators can calculate their latitude and longitude, enabling accurate navigation without modern electronic aids. Published annually by the U.S. Naval Observatory, it remains a vital resource for traditional celestial navigation and safe sea voyages.