I have heard a certain statement, which can be summarized succinctly into "we live in a local bubble", implying that solar system is located in an intestrellar dust underdensity region.
This region is allegedly produced by a supernova explosion, which happened near the Sun in the distant past. The bubble size was claimed to be of order of few tens of parsec, and the fact of its existence allows one to easier deal with dust extinction for nearby stars.
Another claim I have heard about this bubble, is that this concept is obsolete nowadays, for if even if there were a supernova taking place near the Sun, gas diffusion timescales are short enough, so that no vestige would have remained from this past event by now.
I would like to ask you, therefore, to comment on the text above and in particular indicate, whether such an underdensity really exists, and what do we know about it.