Does the Second Caustic Ring of Dark Matter Cause the Monoceros Ring of Stars ?

Understand

Caustic rings of dark matter were predicted to exist in the plane of the Galaxy at radii $a_n \simeq 40 {\rm kpc}/n$ 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.