Also known as: Astronomical Applications Department

The Astronomical Applications Department of the U.S. Naval Observatory provides authoritative products - almanacs, software, and web services - and precise astronomical data - Sun and Moon rise and set times, Moon phases, eclipses, seasons, positions of solar system objects, and other data. Astronomical Information Center Background information on common astronomical phenomena, calendars and time, and related topics The Astronomical Almanac is a joint publication of the U. S. Nautical Almanac Office in the United States (USNO) and Her Majesty's Nautical Almanac Office (HMNAO) in the United Kingdom. The online version 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 world-wide standard for such information.

Author: U.S. Naval Observatory

http://aa.usno.navy.mil/