Hello everybody, I started a pull request https://github.com/scipy/scipy/pull/9556 that gives the user the ability to select a method to determine the vertices of a Voronoi tesselation of a spherical surface. I also expanded the tests accordingly. Someone more experienced should please do a code review on it. To see what that kind of difference (or not) it can make, look at e.g. https://www.redblobgames.com/x/1842-delaunay-voronoi-sphere/#voronoi I needed this functionality and found it easiest to just extend the existing scipy.spatial.SphericalVoronoi class. Others might find it useful as well. Oliver