A hidden magnetic twist inside the Milky Way may rewrite what scientists know about how our galaxy is held together. Astronomers have uncovered a strange magnetic “flip” hidden inside the Milky Way. Using a new radio telescope, researchers mapped the galaxy’s magnetic field in unprecedented detail and discovered that a mysterious reversal in the Sagittarius Arm cuts diagonally across space. The finding could reshape how scientists understand the structure and future evolution of our galaxy.

For hundreds of years, astronomers have studied the night sky in an effort to understand the forces shaping the universe. One of the most important, yet invisible, forces inside the Milky Way is its magnetic field. Now, researchers at the University of Calgary are producing one of the clearest views yet of that hidden structure.

“Without a magnetic field, the galaxy would collapse in on itself due to gravity,” says Brown, a professor in the Department of Physics and Astronomy at the University of Calgary.