Liaison: International Earth Rotation and Reference Systems Service (IERS)


Links between the BIPM and the IERS

  • The IERS decides on the dates of application of leap seconds on UTC.


The IERS was established by the International Astronomical Union and the International Union of Geodesy and Geophysics.

The IERS provides data on Earth orientation, on the International Celestial Reference System/Frame, on the International Terrestrial Reference System/Frame, and monitors the difference between UT1 and UTC.



Dr Patrizia Tavella

Time Department

Asset Publisher