Data, Products and Tools

The IERS provides data on Earth orientation, the International Celestial Reference System/Frame (ICRS/ICRF), the International Terrestrial Reference System/Frame (ITRS/ITRF), and geophysical fluids. It also maintains IERS Conventions, which include models, constants, and standards.

For regular updates on changes to IERS data, products, and tools, please register as IERS user and subscribe to IERS Messages.

The IERS provides rapid, monthly, and long-term Earth orientation data, as well as leap second announcements and announcements of DUT1, available through bulletins or data files.
more...

The International Celestial Reference Frame (ICRF) consists of equatorial coordinates of extragalactic radio sources observed with VLBI, realizing an ideal reference system, the International Celestial Reference System (ICRS).

ICRF   ICRS

The International Terrestrial Reference Frame (ITRF) is a set of points defined by their three-dimensional Cartesian coordinates, realizing the ideal reference system, the International Terrestrial Reference System (ITRS).

ITRF   ITRS

Global geophysical fluids data provide information related to Earth’s rotation variations, gravity field changes, and geocenter motion, driven by mass transports in the global geophysical fluids, including the atmosphere, oceans, hydrology, tides, mantle, and core.
more...

The IERS Conventions define the standard reference system used by the IERS, incorporating conventional models, constants, and standards.
more...

Several tools are available for visualizing and analyzing IERS data and products.
more...

The IERS also publishes Annual Reports, Technical Notes and other documents. The content of product descriptions is based on a survey conducted by the IERS Analysis Coordinator regarding IERS products.