Beware of the fraudulent hardcover copy of this book. It is a photocopy of the real book and produced without a license. Paradise Cay Publications is the only entity in the United States other than the US Government legally authorized to publish the full contents of the Nautical Almanac. The cornerstone for all celestial navigation, listing the celestial bodies used for navigation, a sight reduction table, and other information valuable to the offshore navigator. The content of this edition is identical to the United States Naval Observatory edition.