" Recall that the Milky Way is a disk galaxy, meaning most of the stars and gas lie in a thin disk, about 130,000 light-years across but only roughly 2,000 light-years in thickness. The Sun is located at a distance of about 27,000 light-years from the galactic center, and happens at this moment to be close to the galactic midplane—less than 100 light-years away. It is also at the edge of a spiral arm. "

― Lisa Randall , Dark Matter and the Dinosaurs: The Astounding Interconnectedness of the Universe