Scientists discover huge magnetic toroids in the Milky Way halo

The origin and evolution of cosmic magnetic fields is a long-standing unsolved question at the frontier of astronomy and astrophysics research and has been selected as one of the key areas of investigation for many major world-class radio telescopes, including the Square Kilometer Array (SKA) under construction. To determine the large-scale magnetic field structures in the Milky Way has been a major challenge for many astronomers in the world for decades.