International Earth Rotation Service (IERS)

IERS was established by the International Astronomical Union and the International Union of Geodesy and Geophysics in 1987, initially known as the International Earth Rotation Service, and began operating on January 1, 1988. In 2003, it was renamed as the International Earth Rotation and Reference System Service.

The main goal of IERS is to provide the following services to the astronomy, geodesy, and geophysics communities:

• The International Astronomical Reference System (ICRS) and its implementation, the International Astronomical Reference Framework (ICRF).

• International Earth Reference System (ITRS) and its implementation, International Earth Reference Framework (ITRF).

• Study the Earth's directional changes and the Earth's directional parameters required for conversion between ICRF and ITRF.

• Geophysical data is used to interpret the temporal/spatial variations of ICRF, ITRF, or Earth directional parameters, and to model these variations.

• Encourage international adherence to standards, constants, and models (i.e. conventions).

Since January 1, 2001, IERS has had a new structure, which is also reflected in this new website.