For a long time unexplained, the polar auroras – borealis in the north, austral in the south – are proof of an aggression: that of the Sun on the Earth. When the solar winds disturb the magnetic shield around the Earth, it deforms and stretches like a rubber band. By relaxing this “rubber band” causes the high speed catapult of particles which converge towards the poles. Excited, the atoms in the upper atmosphere then emit green, violet, pink or red light.
