Publications

Annual Astronomical and Navigational Almanacs:

• The Astronomical Almanac contains precise ephemerides of the Sun, Moon, planets, and satellites; data for eclipses and other astronomical phenomena for a given year; and serves as a worldwide standard for such information.
• The Nautical Almanac contains the following data tabulated at hourly intervals to a precision of 0.1 arcminute: the Greenwich hour angle and declination of the Sun, Moon, and navigational planets; the Greenwich hour angle of Aries; positions of the navigational stars; rise and set times of the Sun and Moon for a range of latitudes; and other data. Each edition also contains a sight reduction table; sight reduction formulas; and various correction tables for sight reduction. There is a useful concise sight reduction form at the back of the book. The Nautical Almanac is available several months in advance of its edition date.  Each edition contains a sight reduction table; sight reduction formulas; and various correction tables for sight reduction. There’s a useful concise sight reduction form at the back of the book.  For over 150 years the United States Nautical Almanac Office has published The Nautical Almanac, first as part of the American Ephemeris and Nautical Almanac, and then on its own, to provide the US Navy with a convenient form of the astronomical data used for celestial navigation. This book is still the standard resource for marine celestial navigation for the U.S. Navy. 
• The Air Almanac contains the astronomical data required for air celestial navigation. The download-version contains the same data found on the CD-ROM, but in a single bookmarked PDF.  It provides the following data tabulated at 10-minute intervals to a precision of 1 arcminute: the Greenwich hour angle and declination of the Sun, Moon, and three navigational planets; the Greenwich hour angle of Aries; rise and set times of the Moon for a range of latitudes; and other data. Each edition also contains sky diagrams for each month; sunrise, sunset, and twilight tables; and positions of the navigational stars.  HMNAO maintains the copyright on the material it produces.  You may download a PDF copy of the current Air Almanac here.
• Astronomical Phenomena is a small, useful booklet that contains general interest material preprinted from The Astronomical Almanac. It is published jointly by the U.S. Naval Observatory and Her Majesty's Nautical Almanac Office two years in advance of its date. It includes such subjects as:
  • dates for Solar equinoxes, solstices, phases of the Moon
  • eclipse maps
  • dates for various planetary phenomena
  • visibility and magnitudes of the planets
  • dates for some religious and civil holidays
  • chronological eras and cycles
  • the equation of time and declination of the Sun
  • sunrise/set, moonrise/set times
  • the position of Polaris
  You may download a PDF of the current (2021) Astronomical Phenomena from Her Majesty's Nautical Almanac Office here.
   
• How to Order:  Hardcover copies of the above publications may be ordered online from the U.S. Government Printing Office bookstore.  You may also use this order form for postal or FAX orders. 

U.S. Naval Observatory Special Publications:

• U.S. Naval Observatory Special Publications

Technical Reports:

• USNO Technical Reports
• Related Publications by Other Institutions