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The Astronomical Almanac is a joint publication of the U.S. Nautical Almanac Office, United States Naval Observatory (USNO), in the United States and Her Majesty's Nautical Almanac Office (HMNAO), United Kingdom Hydrographic Office (UKHO), in the United Kingdom.
With a focus on engineering and scientific references, the collection contains over 800 books. Subject areas include chemistry and plastics, materials science, environmental science, microelectronics materials, electrical engineering, electronic engineering, chemical engineering, systems engineering, food sciences, and mechanical engineering.
The references are deeply searchable with advanced field searching, allowing users to search across multiple sources to find specific data. For best results, download the most current Adobe Acrobat Reader.