DEPARTMENT 1 : Reference systems and Geodynamics

Section 1 : Time, Earth rotation and Space geodesy

Project 4. Earth rotation

The rotation of the Earth is not constant and presents small fluctuations: days are sometimes a few milliseconds longer or shorter. In addition, the orientation of the rotation axis changes with time.
The rotation axis moves inside the Earth, a phenomenon called polar motion, and moves also with the Earth like a top in space, a motion called precession/nutation. This last motion is one of the major research works in the field of Earth rotation at the Royal Observatory of Belgium and is directly related to Earth’s interior and the geophysical fluids (oceans, atmosphere, liquid core), which perturb the rotation of the Earth.

Staff