text:   in the Milky Way",7,"['Paper day! <LINK>\n\n""Orbital Torus Imaging"" is a new method for dynamical inference (measuring the Galactic mass / dark matter distribution, etc.) that exploits the existence of element-abundance gradients, like these from @APOGEEsurvey: <LINK>', 'Conceptually, the method words because the element-abundance contours ""show"" us the shapes of orbits, demonstrated here with vertical kinematics of stars (in z–vz) https://t.co/gxAGZADoCz', 'You can think of ""Orbital Torus Imaging"" as a replacement for Jeans modeling that will be more precise and requires fewer assumptions in practice: We only require that orbits are phase-mixed locally in action-space', ""We do a simple demonstration in this paper using @APOGEEsurvey data: Using just 8 element abundances, and only modeling the vertical kinematics of stars (but don't assume separability) we get constraints on the disk mass and scale height that are precise to a few percent https://t.co/qde8OQI18F"", 'Plus, now we finally have a (dynamical) use for all of those millions x 30  element abundances that spectroscopic surveys like @APOGEEsurvey, @galahsurvey, LAMOST, etc. are delivering :)', ""As usual in Galactic dynamics, there are many caveats and we make many assumptions, but I'm excited to see what we will learn when we apply this to larger data sets and with more ambitious / flexible models of the Galactic mass!"", 'Thanks to everyone that contributed and helped with this project along the way! @davidwhogg @kvj_astro @melissakness @FritzZwicky @rareflwr41 + many others']",20,12,1478