CPO – Celestial Pole Offsets

Celestial Pole Offsets (CPO) are small corrections to the modeled position of the Celestial Intermediate Pole (CIP), accounting for differences between theoretical precession-nutation models and actual Earth motion. They are part of the Earth Orientation Parameters (EOP) that connect the International Celestial Reference Frame (ICRF) with the International Terrestrial Reference Frame (ITRF). CPO values ensure precise Earth rotation modeling, supporting accurate satellite navigation, geodesy, and timekeeping.

More Info: https://geodesy.science/item/earth-orientation-parameter