Astronomical Applications
This US Naval Observatory Website is undergoing modernization and will be offline starting Thursday, 24 October 2019. The expected completion of work and return of service is estimated as 30 April 2020. Please visit https://www.usno.navy.mil/USNO/about-us and submit a Requirements Form to the USNO PAO if the information you are seeking is not accessible via another means.
Data Services
Sun and Moon rise and set times, Moon phases, eclipses, seasons, positions of solar system objects, and other data
- Complete Sun and Moon Data for One Day
- Sun or Moon Rise/Set Table for One Year
- Phases of the Moon
- more...
Astronomical Information Center
Background information on common astronomical phenomena, calendars and time, and related topics
- Rise, Set, and Twilight Definitions
- World Time Zone Map
- Phases of the Moon and Percent of the Moon Illuminated
- more...
Almanacs and Other Publications
Astronomical and navigational almanacs, special publications, research reports
Software Products
Computer almanac for PCs and Macs, and more
