Astronomical Applications Department
of the U.S. Naval Observatory
Welcome to the web pages of the Astronomical Applications Department of the U.S. Naval Observatory . Our products -- almanacs, software, and web services -- provide precise astronomical data for practical applications, serving the defense, scientific, commercial, and civilian communities.
Data Services
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.
Publications
Astronomical and navigational almanacs, special publications, and research reports.
Software Products
Astronomy source code for advanced users.