A survey has provided the most detailed look yet at a mysterious ring of stars at the fringes of the Milky Way.

Using data from the Pan-STARRS1 telescope in Hawaii, Colin Slater and Eric Bell at the University of Michigan in Ann Arbor and their colleagues show that the Monoceros Ring appears as wispy stellar streams emerging from the Milky Way's outer disk.

There is debate over how the ring was created, with theories suggesting that it is either a part of the Galactic disk that was warped by the influence of nearby dwarf galaxies or the remnants of a dwarf galaxy that was unfurled in an encounter with the Milky Way. Neither scenario explains all the details seen in the survey, however, suggesting that the models need improving.

Astrophys. J. 791, 9 (2014)