The Local Bubble is a cavity of thin, hot gas around the Sun, blown out of the interstellar medium by a series of supernovae, with the Sun sitting inside it.
About The Local Bubble
Interstellar space near the Sun is emptier than average. Absorption by gas towards nearby stars, a faint glow of soft X-rays from every direction and three-dimensional maps of dust all point to the same thing: the Sun lies inside a large, irregular cavity whose walls are dense with cold gas and dust.
The cavity is thought to have been carved by massive stars in nearby young groups that exploded as supernovae one after another. Traces of radioactive iron in deep-sea crust support recent nearby explosions. Maps of the bubble’s surface show that many of the nearest star-forming clouds, in Ophiuchus, Lupus, Chamaeleon, Taurus and Perseus, sit on its expanding shell.
What you see in the piece
Press B to show the bubble’s outline. Its wall is where the dust map thickens, which is why the nearby molecular clouds cluster on it.
Measured or modelled
The bubble’s shape comes from three-dimensional dust maps, and its outline in the piece is a model of that surface; its age and the exact sequence of supernovae that made it are inferred.
Questions
What is the Local Bubble?
A region of hot, thin gas surrounding the Sun, emptied by supernova explosions, with walls of denser gas and dust where nearby stars are forming.
Is the Sun inside the Local Bubble?
Yes. The Sun lies within the bubble, currently passing through a small, cooler cloud of gas inside it.