The origin of the local bubble

The Sun is located in a low-density region of the interstellar medium parti ally filled with hot gas that is the likely result of several nearby supern ova explosions within the last 10 Myr. Here we use astrometric data to show that part of the Scorpius-Centaurus OB association was located closer to t he present position of the Sun 5-7 Myr ago than today. Evolutionary synthes is models indicate that the association must have experienced similar to0 s upernova explosions in the last 10-12 Myr, a prediction that is supported b y the detection of four or five runaway stars escaping from it. The approxi mately six supernovae produced by the Lower Centaurus Crux subgroup are lik ely responsible for the creation of the Local Bubble.