Data Products

IERS Bulletin A (The National Earth Orientation Service Bulletin)

The Bulletin A Web Page

The most recent Earth Orientation Parameters (x, y, and UT1-UTC)

The Radio Optical Reference Frame (RORF)

The Radio Reference Frame Image Database (RRFID)

The Optical Image Database (OID)

Obtaining NEOS VLBI data

The Explanatory Supplement to IERS Bulletins A and B

Historical differences between International Atomic Time (TAI) and Coordinated Universal Time (UTC)

What is Earth Orientation?

What is a leap second?

Would you like to regularly receive EOP data? If so, please fill out and submit a product request form (requires a 'forms' capable browser).

Programs

Earth Orientation Parameters (EOP) analysis and prediction;

Global Positioning System (GPS) data analysis;

the Radio Reference Frame; and

Very Long Baseline Interferometry (VLBI) data analysis.

The Washington Correlator (WACO)

Miscellaneous

United States Naval Observatory (USNO)

International Astronomical Union (IAU)

International Earth Rotation Service (IERS)

International VLBI Service (IVS)

VLBI Group of NASA's Space Geodesy Program

International GPS Service (IGS)