Neutron tie-dye

This is not just computer graphics. It’s the magnetic field of a real bar magnet, imaged using a neutron beam. Neutrons have no electric charge, which enables them to fly straight through a magnetic field and to zip through thick solids unaffected (SN: 3/18/08) But neutrons possess a magnetic moment. Like tiny bar magnets, they will tend to align their magnetic moment with that of a magnetic field.