Need some modern Excel functions for science students and astronomy. On www there are a multitude of UDF that calculate astronomical values. Most of these use an index and repeat the same pre calculation three times to get information like x y z or radius theta phi ... and repeat the same 3 calculation fully if already calculated information is needed. Is there some classes written to calculate these as types with a Boolean to avoid recalculation. I have searched for these astronomy functions put into class modules for modern VBA.. Many of the UDF are adjusted Q basic or earlier. Can any one point me in the direction of a source of these.. Graphics showing earth moon sun moon phases etc as shapes are too slow when the calculations are repeating .