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EO Information Center

General Information about Earth Orientation

General information about Earth Orientation such as units, dates, times, and input data series used.  IERS Conventions, Bulletin B, Bulletin C, and Bulletin D information are also provided.

GPS User Information

Information specifically for GPS users regarding rapid and ultra-rapid products and UTGPS estimates.

Frequently Asked Questions about Earth Orientation

Find answers to some questions regarding Earth Orientation.  Suggested reading for more information.

Read Me Files

Formats for the data files produced.


USNO Master Clock Time
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