Our solar system is encased in a gigantic “magnetic tunnel” that connects two vast regions of our galaxy that seemed to be disconnected.
That’s the conclusion of a recent study in the area of the magnetic fields of the cosmos, a feature of our universe about which there are still many unanswered questions.
This discovery by a team from the University of Toronto (Canada) could be useful to better understand how the universe’s magnetic fields work and how they affect the behavior and evolution of galaxies.
“This model has implications for the development of a holistic model of magnetic fields in galaxies,” the study authors write.
What has been discovered and how can it help improve our understanding of the universe?
The investigation focused on two gigantic structures in our Milky Way galaxy known as the “North Polar Spur” (NPS) and the “Fan Region” (Fan).
The North Polar Spur is a huge band of hot gas that emits X-rays and radio waves.
In turn, the Fan Region is a highly polarized area, whose electric field opens in the shape of a fan. Both regions are visible through radio telescopes and, from Earth, are located on opposite sides of space.
The green lines illustrate how the magnetic filaments form a tunnel structure. — Photo: DUNLAP INSTITUTE FOR ASTRONOMY & ASTROPHYSICS
Until now, these two structures have been studied individually, but work from the University of Toronto shows for the first time that they are connected by a “tunnel” within which our solar system is located.
“Magnetic fields do not exist in isolation,” says Jennifer West, a researcher in galaxy magnetism at the Dunlap Institute for Astronomy and Physics at the University of Toronto and lead author of the study.
“They all need to connect to each other. So the next step is to better understand how this local magnetic field connects to both the larger-scale galactic magnetic field and the smaller-scale magnetic fields of our Sun and Earth.”
This image shows the region of the Milky Way where our Solar System is. The orange lines show the tunnel formed by the Ventilator Region (Fan) and the North Polar Spur (NPS). The red dot represents the Sun. — Photo: DUNLAP INSTITUTE FOR ASTRONOMY & ASTROPHYSICS
The magnetic field of galaxies
Every galaxy has a natural magnetic field, but it is weak, explains Christopher S. Bair, a professor of physics at West Texas A&M University.
“Our galaxy’s magnetic field is about a hundred times weaker than Earth’s magnetic field,” Bair wrote on the Science Questions With Surprising Answers blog.
A galaxy’s magnetic field is created in a similar way to Earth’s magnetic field: through the dynamo effect.
The galaxy’s rotation causes interstellar gas filled with charged particles to move. In this way, the kinetic energy of the moving particles creates a magnetic field.
This magnetic field, in turn, acts on the charged particles, thus amplifying the magnetic field.
The Earth’s magnetic field is 100 times stronger than that of the Milky Way — Photo: Nasa
To discover this “tunnel,” West and his colleagues ran simulations of what Earth’s space would look like if radio waves from the North Polar Spur and Fan Region were emitting light.
In this way, they realized that both regions are connected by structures of magnetic filaments.
“If we could see radio light (waves), we would see this glowing material stretching across the sky in many different directions,” West said.
West refers to a complex system of charged particles and magnetic filaments that form a kind of tunnel that surrounds the solar system and some outer stars.
According to West’s calculations, this tunnel would be about 1,000 light-years long.
This is how our galaxy looks in radio waves — Photo: HASLAM ET AL. (1982) WITH ANNOTATIONS BY J. WEST.
According to the authors of the research, their findings may serve to better understand other filament structures that are increasingly being observed by modern radio telescopes.
“We still do not fully understand the origin and evolution of regular magnetic fields in galaxies and how these fields are maintained,” they write in their study.
“Imagine that we’re sitting inside a tunnel… and the rest of the galaxy is outside that tunnel, and the rest of the universe is outside that tunnel. But we would be inside,” West said.
“Since we’re inside it, we have to look through it all the time. I think it’s a very important first step in understanding the universe more broadly.”