Baffling. The earth isn’t a perfectly smooth solid sphere that never deforms. It is a dynamic object being shaped by all sorts of forces. How do they guarantee

Baffling. The earth isn’t a perfectly smooth solid sphere that never deforms. It is a dynamic object being shaped by all sorts of forces. How do they guarantee 0.1mm error over a year. It must be limited to a small number of high value targets given the techniques used on the article, but still unclear. Just seems wildly complicated to get right.