The International Earth Rotation and Referencesystem Services (IERS) is an International Service under the Federation of Astronomical and Geophysical Data Analysis Services (FAGS). IERS permanently provides homogeneous celestial and terrestrial references and Earth orientation parameters with an accuracy of 1 cm at the surface of the Earth. The global observing activity involves Very Long Baseline Interferometry (VLBI), Lunar Laser Ranging (LLR), Satellite Laser Ranging (SLR), Global Positioning System (GPS) and DORIS with worldwide networks totaling about 250 sites in 1996. The analyses performed by about 30 groups of 10 countries provide the daily monitoring of the Earth orientation parameters as well as the maintenance of the celestial (ICRF) and terrestrial (ITRF) reference frames. The IERS publications are sent or e-mailed or provided by ftp and www to 1000 users in over 60 countries.
For further information link to the IERS home pages
Http://www.iers.org
or contact:
Dr. Bernd Richter
Director Central Bureau of IERS
Bundesamt für Kartographie und Geodäsie
Richard-Strauss-Allee 11
D-60598 Frankfurt am Main
e-mail: richter@iers.org