The magnetism of the thousand-light-year superbubble in which we live

Astronomers have produced a revealing new map of the local cosmos that could help answer questions that were asked decades ago and have been awaiting answers ever since. These questions refer to the origin of stars and the influence that the magnetic fields of the cosmos have on star formation and other phenomena.

The work is the work of Theo O’Neill’s team, from the Center for Astrophysics (CfA), an entity dependent on Harvard University and the Smithsonian Institute, all of these institutions in the United States.

The map reveals the probable magnetic field structure of the Local Bubble, a gigantic “hole” measuring about 1,000 light-years from end to end and within which are our solar system and others. Obviously, it is not a completely empty hole or area in the literal sense of the expression, but an area with an abnormally low density of stars. In that bubble of a thousand light-years there should be many more stars than there are.

Like the holes in a piece of Swiss cheese, there are plenty of these bubbles in our galaxy. The supernova explosions with which high-mass stars end their lives tend to concentrate gas and dust (which are the raw materials for creating new stars) on the outer “surfaces” of the bubbles. These surfaces are, therefore, favorable places for the formation of stars and planets.

Here, the short pink and purple vector lines on the bubble’s surface represent the orientation of the discovered magnetic field. The bubble is inside the Milky Way. (Image: Theo O’Neill/WorldWide Telescope. CC BY-NC)

The Local Bubble has become a hot topic in astrophysics because it is the superbubble in which our solar system is located. In 2020, researchers from Greece and France deduced what the three-dimensional geometry of the local bubble should be. Then, in 2021, scientists at the University of Vienna in Austria and other institutions concluded that the surface of the Local Bubble is the source of all the young stars in this area of ​​the galaxy.

However, general knowledge about superbubbles has been very poor. With the new three-dimensional map of the Local Bubble magnetic field, the scientific community now has new information that could help experts to better explain the evolution of super bubbles, their effects on star formation and their influence on galaxies in general. .

“Making this three-dimensional map of the Local Bubble will help us examine super-bubbles in new ways,” says O’Neill. (Font: NCYT by Amazings)