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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.


Astronomical and navigational almanacs, special publications, and research reports.

Software Products

Astronomy source code for advanced users.

About Us

Infomation about the department and its history.

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