Galaxies like our Milky Way are mysteriously hard to come by in our cosmic backyard. New supercomputer simulations have helped astronomers finally answer why.
The Milky Way sits within a galaxy cluster on the Supergalactic Plane — a billion light-year-wide sheet, or "supercluster," upon which large galaxy clusters are pinned. But other spiral galaxies are surprisingly rare along this gigantic plane, while bright elliptical galaxies are far more common.
