Northern Lights explained. Computer artwork showing the explosion of energy (bright, right) responsible for sudden increases in the brightness and movement of the Northern Lights (Aurora Borealis) on Earth (centre left). Researchers using five NASA satellites have discovered that explosions of magnetic energy a third of the way to the moon power substorms that cause sudden brightenings and rapid movements of the aurora borealis, or Northern Lights. The mechanism that causes this is magnetic reconnection, a common process that occurs throughout the universe when stressed magnetic field lines (lines) suddenly snap to a new shape, like a rubber band that's been stretched too far.