Astronomers recently identified a huge cavity in the Milky Way galaxy created by the explosion of an end-of-life star several million years ago , around which new stars are born. This work, published in The Astrophysical Journal Letters, helps shed light on the role of supernovae in the star formation process.
A major question in the field of star formation is how molecular clouds (star-forming clusters of gas and dust) form from the middle diffuse interstellar (ISM). Recent advances in 3D dust mapping are revolutionizing our view of the structure of ISM. As part of a study, a team has relied on the European Space Agency's Gaia satellite to map the well-known molecular clouds of Perseus and Taurus in 3D, revealing a massive void between the two once elusive structures in previous 2D maps of the region.
“We could see these clouds for decades, but we never knew their true shape, depth or thickness. We also didn't know how far away the clouds were “, Details Catherine Zucker, co-author of the study. “Now we know where they are with only 1% uncertainty, allowing us to discern that void between them “.
According to the study, this bubble-shaped "cavity" is about 500 light-years long wide. “Hundreds of stars are forming or already exist on the surface of this giant bubble “, underlines Shmuel Bialy, of the Institute for Theory and Computation (ITC) of the Harvard-Smithsonian Center for Astrophysics.
These clumps of gas and dust are believed to formed in tandem from the same supernova (explosion of a star at the end of its life) about ten million years ago . These two clouds would have more precisely formed following the same shock wave, demonstrating the powerful effects of such stellar explosions.
According to the team members, this new discovery could thus shed light on how supernovae generate star formation in the Milky Way. "We have two theories:either a supernova ignited at the core of this bubble and pushed the gas out, forming what we now call the 'Perseus-Taurus super-shell “, either a series of supernovae occurring over millions of years created it over time “, continues the scientist. "Anyway, it demonstrates that when a star dies, its supernova generates a chain of events that can ultimately lead to the birth of new stars “.
