lensing and image synthesis

After Marshall gave an MPIA Galaxy Coffee talk about his work on finding Milky-Way-like halos from the output of n-body simulations—a method of using LambdaCDM as a prior on halo properties—we got to work making the gravitational lensing version of the Tractor. We struggled with Python and inheritance, but we got very close. We are trying to synthesize PanSTARRS images before the week is out. On the side, Price-Whelan worked to refactor and resurrect his work on our paper tentatively titled Dear PanSTARRS: Don't co-add your data. Love, Astrometry.net.