Star Formation, Stellar Feedback, and the Ecology of Galaxies

Star Formation, Stellar Feedback, and the Ecology of Galaxies

Local Galactic structure shaped by feedback from three massive complexes

The Gaia space mission and other ground-based surveys have yielded an extraordinary three-dimensional view of the local ISM. Vast cavities and shells are clearly visible in high-resolution 3D spatial maps of interstellar dust. Many young star clusters, often enclosed within these cavities or embedded within the surrounding gas shells, have precise estimates of their 3D positions, 3D velocities, and ages, allowing them to be traced backwards to their birth regions. I present a recent result showing that most (57%) young star clusters within one kiloparsec of the Sun originated in one of just three massive star formation complexes. Together, they likely hosted over 200 supernovae explosions, providing the feedback necessary to power the expansion of the Local Bubble and the kiloparsec-scale Galactic supershell (GSH) 238+00+09, the lowest density cavity in the local ISM. I briefly summarize the properties of these former complexes that are traced by their resulting star cluster “families.” I present ongoing work that unveils spatial-temporal patterns across the families, demonstrating evidence of feedback-driven sequential star formation occurring on scales of hundreds of parsecs over the past 40–60 million years. This process was followed by the formation of the Sco-Cen, Vela, Taurus, and Orion star-forming regions, all beginning when the three cluster families intersected 10–15 million years ago. Finally, I demonstrate how the formation history of one cluster family can be used to constrain the time evolution (~30 Myr) of an expanding supershell (GSH 238+00+09).