In the morning, I got a great email from Ness, showing that we can separate red-clump and non-red-clump red-giant stars at huge confidence, using APOGEE spectra and The Cannon. I also read and gave comments on Malz's first attempt at doing inference with probabilistic redshifts.
At #astrohackny Price-Whelan and I started on the crazy Gaussian-Process blind source separation plan. We also pitched a linear version too and divided up tasks among the various hackers interested in working on the Planck data. We didn't get very far, because we spent most of our hacking time understanding this Lawrence paper (PDF).
In the afternoon, I had the pleasure of being on a committee for the oral candidacy exam of Lukas Heinrich (NYU). He spoke about RECAST, which is a system to permit outsiders to re-interpret LHC ATLAS searches in terms of new or different physics models. The idea is: If a search has been done and it is relevant to some new or different physics, there is no need to do new searches ab initio until the existing searches have been checked for the relevant physics. This all also ties into ideas of preserving workflow and reproducibility and open science, all of which are very relevant to the Moore-Sloan Data Science Environments.