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Earth Orientation Products

USNO, as the IERS Rapid Service/Prediction Center, provides daily, weekly, and long-term data products.  Data files and plots are categorized into daily, weekly, and long-term products.  The Bulletin A, updated every Thursday, is available here.  An archive of past issues of Bulletin A is here.  
Daily Solutions
Daily data files available at IERS.  Updated daily (normally around 17:05 UTC), for highest accuracy real-time applications.
Weekly Solutions
Standard data files available at IERS.  Updated weekly on Thursdays.  Plots of Bulletin A combination and residuals.  Statistical report for contributed series.
Long-term Delta T
Monthly determination of Delta T (TT - UT1) since 1973 and long-term predictions.  Determinations of Delta T are updated approximately quarterly, and long-term predictions from are updated annually.  Data available at cddis.  |  |  Navy FOIA  |  DoD Accessibility/Section 508  |  No Fear Act  |  Open Government  |  Plain Writing Act  |  Veterans Crisis Line  |  DoD Safe Helpline  |  Navy SAPR  |  NCIS Tips  |  Privacy Policy  |  Contact Webmaster
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