# Xiaoping Wu Back to [[Expanding Earth and Plate Tectonics]] **Role:** lead author of Wu, Collilieux, Altamimi, Vermeersen, Gross & Fukumori (2011), *GRL*, [doi:10.1029/2011GL047450](https://doi.org/10.1029/2011GL047450). - The study combined space-geodesy data with gravity and ocean-bottom-pressure models ⚠️ (method summary from memory) and found an average radius change of **0.1 ± 0.2 mm/yr**, which is not significant. - Quote (JPL release, "NASA Research Confirms it's a Small World, After All"): "Our study provides an independent confirmation that the solid Earth is not getting larger at present, within current measurement uncertainties."