How the universe got its large magnetic fields has remained one of the stickiest outstanding problems in astrophysics. Now, researchers have proposed a novel solution: a giant "dust battery" operating when the first stars appeared.
Magnetic fields are everywhere in the universe. Of course, there's Earth's magnetic field, which deflects dangerous cosmic radiation, wiggles our compasses, and guides flocks of migrating birds. But other planets and stars have magnetic fields, too, and the magnetic fields of Jupiter and the sun are more powerful than Earth's.
