What is an aurora?
The earth is surrounded by a magnetic field (called the magnetosphere), much the same as the field a magnet has around it. Certain events on the sun result in waves of energy being radiated from the sun. When these waves hit the earth’s magnetosphere, they energise particles (atoms) in the upper atmosphere. These energised particles are then generally guided along the earth’s magnetic field lines to the north or south poles. Here they tend to release some of their energy. The same way a fluorescent tube releases energy as light, the energy released by these particles is observed as light waves. Depending on the type of atom that was energised, and the amount of energy released, we get different wavelengths, or different colours of light. We then observe this light as an aurora – a silent, beautiful, powerful natural phenomena, which can only be marveled at.
