Alex Drlica-Wagner

This plot shows the positions of stars surrounding the newly discovered dwarf galaxy Reticulum II. Points outlined in black represent stars for which high-resolution optical spectra provided velocity measurements. Red points represent stars that were confirmed to be members of the new dwarf galaxy, while gray points are non-members. (Points that are not outlined do not have velocity measurements.) The number of dark matter-dominated Milky Way satellite dwarf galaxies was increased by one this week. Scientists discovered the newest dwarf…