The Conventions contains detailed information on definitions and models used to determine Earth Orientation.
Refer here for the latest updates to the Conventions.
Please note: This links to the 2003 IERS Conventions.
Please note: This links to the 1996 IERS Conventions.
Units commonly used for Earth Orientation
Date and Time Definitions
interpolate UT1-UTC properly around a leap second.
Data series used in IERS Bulletin AThese are the raw observations which contribute to IERS Bulletin A.
Systematic corrections that are applied to Combination procedure.
Archive of changes to Bulletin A since 2007.
Past issues of Bulletin A are archived at Crustal Dynamics Data Information Center (CDDIS).
Plots of past EOP variations (including comparisons with atmospheric excitation).
Reports the "final" Earth Orientation values.
Leap Second Announcements.
Announcements of DUT1 (UT1-UTC).