(unusual move to answer my own question) In fact this is duplicate: * http://math.stackexchange.com/questions/914152/how-to-mark-rational-points-on-a-sphere and the rational points are of course easy to find $$ x=\frac{2u}{u^2+v^2+1};y=\frac{2v}{u^2+v^2+1};z=\frac{u^2+v^2-1}{u^2+v^2+1} $$ There is even a proof of equidistribution as a result of [Duke](http://www.math.ucla.edu/~wdduke/preprints/rational.pdf) He shows that: $$ \frac{\sum_{h(x)\leq T} \psi(x)}{\sum_{h(x)\leq T} \;\;1\;\;} \to \int_{S^2} \psi \, d\mu $$ for any function $\psi: S^2 \to \mathbb{C}$. There is also general discussion of Bjorn Poonen in genral on [rational points on varieties](http://www-math.mit.edu/~poonen/papers/Qpoints.pdf)