stars

As always, MPIA Milky Way group meeting was a pleasure today, featuring short discussions led by Nicholas Martin (Strasbourg), Adrian Price-Whelan, and Andy Casey. Casey showed his developments on The Cannon and applications to new surveys. Price-Whelan spoke about our ability to see possible warps (coherent responses) in the Milky Way disk from interactions with satellites. Martin showed amazing color-magnitude diagrams of stars in Andromeda satellite galaxies. So. Much. Detail.

Chaos reigned around me. Jonathan Bird and Melissa Ness worked on the Disco concept. Anna Y. Q. Ho, working on a suggestion from Casey, found Li lines in (a rare subsample of) LAMOST giants, leading to a whole new insta-project on Li. Price-Whelan figured out multiple methods for initializing and running MCMC on our single-line binary stars, initializing from either the prior or from literature orbits. It looks like many (or maybe all) of the APOGEE variable-velocity stars have multiple qualitatively different but nonetheless plausible orbital solutions. Casey and I conceived of a totally new way to build The Cannon as a local model for every test-step object; a non-parametric Cannon if you wish? I spoke with Jeroen Bouwman (MPIA) about his (very promising) work using Dun Wang's Causal Pixel Model to fit the Spitzer data on transit spectroscopy for a hot Jupiter.