Short answers, pulled from the story.
The Local Bubble is a vast cavity within the Orion Arm of our galaxy that stretches at least 1000 light years across the Milky Way. This region contains the nearest stars and brown dwarfs known to astronomers while maintaining an exceptionally low density of neutral hydrogen atoms.
Scientists now believe that supernovae from the Scorpius, Centaurus association created the structure through multiple explosions rather than a single source. Research indicates that 14 to 20 supernovae originated from subgroups Lower Centaurus, Crux and Upper Centaurus, Lupus within the past ten to twenty million years.
Our solar system has traveled through this region for five to ten million years and entered the bubble around five million years ago according to recent models. The Sun currently resides inside the Local Interstellar Cloud which formed where the Local Bubble met the Loop I Bubble.
A small observatory called CHIPSat launched in February 2003 and operated until April 2008 to examine the hot gas within the Local Bubble directly. The Extreme Ultraviolet Explorer mission studied EUV sources between 1992 and 2001 while researchers reported the first three-dimensional map using diffuse interstellar bands in 2019.
Expanding shockwaves collected debris to trigger the birth of nearby young stars as confirmed by a paper published in Nature in January 2022. New stars typically appear in molecular clouds like the Taurus molecular cloud or open star clusters such as the Pleiades under similar conditions created by the expanding surface.