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United States Naval Observatory
Astronomical Applications Department
Home
Our Commands
United States Naval Observatory
Astronomical Applications Department
ABOUT US
Mission & Vision
History
Naval Oceanography One Pager
End of Year Graphic 2022
LEADERSHIP
Commander
Technical Director
Command Master Chief
All Leadership
OUR COMMANDS
Naval Oceanographic Office
Fleet Numerical Meteorology & Oceanography Center
United States Naval Observatory
News from the Naval Observatory
Earth Orientation Department
Precise Time Department
The USNO Master Clock
The USNO Master Clock
Time Dissemination at the USNO
USNO Alternate Master Clock (AMC)
Cesium Atomic Clocks
Hydrogen Masers at the USNO
Rubidium Fountain Clocks
USNO Time Scales
International Time Scales and the BIPM
Definitions of Systems of Time
Global Positioning System
Global Positioning System Overview
USNO GPS Data Categories Explanation
CGGTTS Data Format
USNO GPS Time Transfer
Leap Seconds
GPS Information: SA, DGPS, Leap Seconds, etc.
GPS Week Number Rollover
GPS Timing Data and Information
USNO Format Explanation
USNO Computer Display Clocks
Two-Way Satellite Time Transfer (TWSTT)
Telephone Time
Network Time Protocol (NTP)
US Eastern Time Zone NTP Servers
US Mountain Time Zone Servers
DoD Customer Servers
Astronomical Applications Department
Celestial Reference Frame Department
Senior Enlisted Advisor
Careers at the USNO
Naval Oceanography Operations Command
Fleet Weather Center - Norfolk
National Ice Center
Fleet Weather Center - San Diego
Joint Typhoon Warning Center
Naval Oceanography Anti-Submarine Warfare Center
Navy DoD Supercomputing Resource Center
PRESS ROOM
News Stories
Photo Gallery
Video Gallery
Public Use of Limitations
CONTACT US
Astronomical Applications Department
The Astronomical Applications Department of the U.S. Naval Observatory computes, from fundamental astronomical reference data, the position, brightness, and other observable characteristics of celestial bodies, as well as the circumstances of astronomical phenomena. Our products -- almanacs, software, and web services -- provide precise astronomical data for practical applications, serving the defense, scientific, commercial, and civilian communities. The department also conducts scientific studies in celestial mechanics, navigation, and positional astronomy to enable it to meet future needs.
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
Computer almanac for PCs and Macs, and more.
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