出典:Wikipedia
出典:『Wikipedia』 (2011/04/29 00:35 UTC 版)
The Local Bubble is a cavity in the interstellar medium (ISM) of the Orion Arm of the Milky Way. It is at least 300 light years across and has a neutral hydrogen density of about 0.05 atoms per cubic centimetre, or approximately one tenth of the average for the ISM in the Milky Way (0.5 atoms/cc), and half that for the "Local Fluff", or Local Interstellar Cloud (0.1 atoms/cc). The hot diffuse gas in the Local Bubble emits X-rays.