The 490-light-year-wide void is located among the constellations Perseus and Taurus, and was formed by one powerful supernova or a series of such events some 10 million years ago, according to new research from the Harvard & Smithsonian Center for Astrophysics.
The location of the newly-discovered giant cavity within the Milky Way Galaxy is depicted on the right; a zoomed in view of the cavity (left) shows the Perseus and Taurus molecular clouds in blue and red, respectively; though they appear to sit within the cavity and touch, new 3D images of the clouds show they border the cavity and are quite a distance apart. Image credit: Alyssa Goodman / Harvard & Smithsonian Center for Astrophysics.
The newly-discovered void is surrounded by two star-forming regions: the Perseus and Taurus molecular clouds.
“Hundreds of stars are forming or exist already at the surface of this giant bubble,” said Dr. Shmuel Bialy, a postdoctoral researcher at the Institute for Theory and Computation at the Harvard & Smithsonian Center for Astrophysics.
“We have two theories — either one supernova went off at the core of this bubble and pushed gas outward forming what we now call the ‘Perseus-Taurus Supershell,’ or a series of supernovae occurring over millions of years created it over time.”
“The finding suggests that the Perseus and Taurus molecular clouds are not independent structures in space. But rather, they formed together from the very same supernova shockwave.”
“This demonstrates that when a star dies, its supernova generates a chain of events that may ultimately lead to the birth of new stars.”
Dr. Bialy and colleagues used data from ESA’s Gaia satellite to create the 3D maps of the void and surrounding Perseus and Taurus molecular clouds.
These maps represent the first-time molecular clouds have been charted in 3D.
“We’ve been able to see these clouds for decades, but we never knew their true shape, depth or thickness,” said Dr. Catherine Zucker, a postdoctoral researcher at the Harvard & Smithsonian Center for Astrophysics.
“We also were unsure how far away the clouds were.”
“Now we know where they lie with only 1% uncertainty, allowing us to discern this void between them.”
“There are many different theories for how gas rearranges itself to form stars,” she added.
“Astronomers have tested these theoretical ideas using simulations in the past, but this is the first time we can use real — not simulated — 3D views to compare theory to observation, and evaluate which theories work best.”
The findings appear in two papers in the Astrophysical Journal Letters and the Astrophysical Journal.
_____
Shmuel Bialy et al. 2021. ApJL; doi: 10.3847/2041-8213/ac1f95
Catherine Zucker et al. 2021. ApJ; doi: 10.3847/1538-4357
