The Commercial Nautical Almanac provides essential astronomical information for every kind of sea going vessel. Astronomical data for the Sun, Moon, Planets and Stars for use in fixing position at sea from sextant observations. In addition it gives times of sunrise, sunset, twilights, Moonrise and Moonset for use in planning observations; all necessary interpolation and altitude correction tables; phases of the Moon; Pole Star table; diagrams and notes for identification of stars and planets; information on eclipses of the Sun and Moon; and the standard times of most countries of the World. This is US version of the UK Nautical Almanac and is essentially a copy with adverts.