Rings and Radial Waves in the Disk of the Milky Way

Abstract: The Monoceros Ring and the Triangulum Andromeda Stream (or Ring) are explained 
by a stellar disk that extends to at least 25 kpc, and oscillates up and down through the 
Galactic plane.  We show that there is an asymmetry in the main sequence star counts on 
either side of the Galactic plane, as one looks towards the Galactic anticenter.  The oscillations 
are aligned with the spiral arms of the Milky Way, and are plausibly consistent with a 
Sagittarius dwarf-sized galaxy plunging through the disk.  Evidence from recent literature that 
supports an interaction between the Milky Way's disk and its satellites, and their association 
with spiral structure, will be reviewed.