Astronomy Tea Talk

Given its proximity, the solar neighborhood has long been considered a fundamental laboratory for understanding how stars form. However, until very recently, this understanding was largely based on static "plane of the sky" views, making it extraordinarily challenging to build a 3D physical picture of dense gas and young stars using 2D integrated quantities. In this talk, I will discuss how new 3D spatial and dynamical constraints from Gaia have transformed our understanding of star formation near the Sun. I will show how essentially all nearby star-forming complexes lie on the surface of the Local Bubble, and that their young stars show outward expansion perpendicular to the bubble's surface. Using these young stars' motions to reconstruct the star formation history of our solar neighborhood, I will explain how a set of supernova explosions beginning 14 Myr ago powered the expansion of the Local Bubble. This expansion swept up the ambient interstellar medium into an extended shell that has now fragmented and collapsed into the most prominent nearby star-forming complexes, in turn providing strong observational evidence for supernova-driven star formation. I will conclude by discussing the relationship between the Local Bubble and other recently discovered structures (the Radcliffe Wave and the Perseus-Taurus Supershell), which together provide new context for understanding triggered star formation in the larger galactic ecosystem.