Aurora

Aurora

The luminous bands of colour seen in the night sky. These occur when charged particles from the sun (solar wind) interact with the gases in the Earth's atmosphere. In the Southern hemisphere these are known as Aurora australis (southern lights), in the north they are Aurora borealis (northern lights).
The solar wind that produces large aurora also disturbs terrestrial magnetism, interfering with radio, telephone, and telegraph transmission. Intense aurora follow high sun spot activity, a cycle that lasts about 11 years. [AM] {GC} {WW}