Magnetars are some of the strangest and most powerful objects in the Universe. They are a special type of neutron star with magnetic fields far stronger than anything scientists can create on Earth. These extreme magnetic fields are known to produce powerful bursts of X-rays and gamma rays. Magnetars have also been linked to some fast radio bursts, which are extremely short but powerful flashes of radio waves from deep space. Now, researchers Servais and Chamel have found that the strongest magnetic fields may do something even more surprising: they can change the structure of a magnetar's crust. Their study shows that magnetic fields can affect not only charged particles such as electrons, but also free neutrons. When the magnetic field becomes extremely strong, the spins of free neutrons become organized. This process, called neutron spin polarization , changes the boundary between the different layers of the magnetar's crust. The discovery could help scientists understand ma...