Frankel, NeigeSanders, JasonTing, Yuan-SenRix, Hans-Walter2022-07-142022-07-140004-637Xhttp://hdl.handle.net/1885/268846A star in the Milky Way’s disk can now be at a Galactocentric radius quite distant from its birth radius for two reasons: either its orbit has become eccentric through radial heating, which increases its radial action JR (“blurring”), or merely its angular momentum Lz has changed and thereby its guiding radius (“churning”)N.F. acknowledges support from the International Max Planck Research School for Astronomy and Cosmic Physics at the University of Heidelberg (IMPRS-HD). J.L.S. acknowledges the support of the Royal Society and the Leverhulme and Newton Trusts. H.-W.R. received support from the European Research Council under the European Union’s Seventh Framework Programme (FP 7) ERC grant agreement No. [321035]. Y.S.T. is grateful to be supported by the NASA Hubble Fellowship grant HST-HF2-51425 awarded by the Space Telescope Science Institute.application/pdfen-AU© 2020. The American Astronomical SocietyGalaxy abundancesGalaxy stellar disksMilky Way GalaxyMilky Way diskMilky Way evolutionMilky Way dynamicsGalaxy dynamics202010.3847/1538-4357/ab910c2021-08-01