Published online by Cambridge University Press: 12 April 2016
The International Earth Rotation Service (IERS) was established in 1987 by the International Astronomical Union (IAU) and the International Union of Geodesy and Geophysics (IUGG), and it began operation on 1 January 1988. The primary objectives of the IERS are to serve the astronomical, geodetic and geophysical communities by providing the following:
• The International Celestial Reference System (ICRS) and its realization, the International Celestial Reference Frame (ICRF).
• The International Terrestrial Reference System (ITRS) and its realization, the International Terrestrial Reference Frame (ITRF).
• Earth orientation parameters required to study Earth orientation variations and to transform between the ICRF and the ITRF.
• Geophysical data to interpret time/space variations of the ITRF with respect to the ICRF, i.e., of the Earth orientation parameters, and to model such variations.
• Standards, constants and models (i.e., conventions) encouraging international adherence.
This presentation primarily covers the first three IERS functions from the operational point of view.