This accessible and visually engaging explainer introduces the fundamentals of Very Long Baseline Interferometry (VLBI) and shows how radio telescopes around the globe measure distances of thousands of kilometres with millimetre precision. It highlights contributions to the International Terrestrial Reference Frame, satellite navigation, and Earth observation, and showcases Australia’s role in global VLBI operations.

The Canadian Geophysical Union (CGU) announces the opening of abstract submissions for the 2026 Scientific Meeting, to be held May 24–27, 2026, in Halifax, Canada. The Geodesy Section will offer a comprehensive program covering advances in gravity field modelling, geoid and height system modernization, GNSS/GNSS-IR, InSAR, geodynamics, deformation monitoring, satellite missions, and innovations in gravimetry. International contributions from the IAG community are encouraged. Travel support for students and Early Career Researchers is available. The abstract submission deadline is January 10, 2026.

Discover Satellite Laser Ranging (SLR) – lasers from ground stations measure satellite and Moon positions with millimeter precision. SLR supports the Terrestrial Reference Frame, tracks Earth rotation, tectonic motion, improves gravity and sea level models, and tests relativity. Explore the science behind these precision measurements in our Geodesy Cartoon.