The Local Bubble is a cavity in the interstellar medium (ISM) in the Orion Arm of the Milky Way. It contains, among others, the Local Interstellar Cloud, G-cloud, and the Solar System. It is at least 300 light years across and has a neutral-hydrogen density of about 0.05 atoms/cm³, or approximately one tenth of the average for the ISM in the Milky Way (0.5 atoms/cm³), and one sixth that of the Local Interstellar Cloud (0.3 atoms/cm³). The hot diffuse gas in the Local Bubble emits X-rays.