Our solar system is located in the outer regions of the Milky Way, a disk-shaped galaxy with an approximate diameter of 100,000 light years. From Earth, its appearance can only be observed indirectly, by measuring positions and movements of stars and gas clouds. In addition to luminous stars, a substantial portion of the visible matter in our Milky Way is interstellar gas. Gas clouds in the so-called central molecular zone (CMZ) — the innermost 1,500 light years of the Milky Way — move on an elliptical central disk that has two spiral arms. A comprehensive model has now been used to simulate this motion.