"How did our galaxy form, and and when did its neighbors arrive? We found all the dark matter halos in a simulation of the evolution of dark matter in the universe that had subhalos with speeds, distances and masses that matched the Magellanic Clouds, and then visualized one of them to show what the Milky Way’s development may have been like. The Magellanic Clouds likely arrived together, recently!" - Risa Wechsler video credit: Busha, Kaehler, Marshall & Wechsler, KIPAC/Stanford University.  Further information: