The Potential for Unifying Global‐Scale Satellite Measurements of Ground Displacements Using Radio Telescopes

The expansion of globally consistent satellite-radar imagery presents new opportunities to measure Earth-surface displacements on intercontinental scales. Yet global applications, including a complete assessment of the land contribution to relative sea-level rise, first demand new solutions to unify relative satellite-radar observations in a geocentric reference frame. The international network of Very Long Baseline Interferometry telescopes provides an existing, yet unexploited, link to unify satellite-radar measurements on a global scale. Proof-of-concept experiments reveal the suitability of these instruments as high-amplitude reflectors for satellite radar and thus provide direct connections to a globally consistent reference frame. Automated tracking of radar satellites is easily integrated into telescope operations alongside ongoing schedules for geodesy and astrometry. Utilizing existing telescopes in this way completely avoids the need for additional geodetic infrastructure or ground surveys and is ready to implement immediately across the telescope network as a first step toward using satellite radar on a global scale.