Recent And Anticipated Changes To The International Earth Rotation And Reference Systems Service (Iers) Conventions

The International Earth Rotation and Reference Systems Service (IERS) Conventions provides the international standard for models and constants related to the transformation between the terrestrial and the celestial reference frames. These includeadopted values of physical constants,the definitions and realizations of terrestrial, celestial, and dynamical reference systems,the transformation between frames,geopotential model,models for the displacement of reference points, model for the tidal variation in the Earth's rotation,tropospheric models, andrelativistic models.As these models provide the link between terrestrial, celestial, and dynamical reference frames, they can be a crucial component of navigation and targeting. The IERS Conventions Center is preparing to release a new version of the IERS Conventions with an anticipated publication date of 2009.