Caustic rings of dark matter were predicted to exist in the plane of the Galaxy at radii a _ { n } \simeq 40 ~ { } { kpc } / n for n = 1 , 2 , 3.. .
The recently discovered Monoceros Ring of stars is located near the n = 2 caustic , prompting us to consider a possible connection between these two objects .
We identify two processes through which the Monoceros Ring of stars may have formed .
One process is the migration of gas to an angular velocity minimum at the caustic leading to enhanced star formation there .
The other is the adiabatic deformation of star orbits as the caustic slowly grows in mass and radius .
The second process predicts an order 100 % enhancement of the density of disk stars at the location of the caustic ring .