Northern light in Sweden

An aurora (plural: auroras or aurorae),[a] sometimes referred to as polar lights (aurora polaris), northern lights (aurora borealis), or southern lights (aurora australis), is a natural light display in the Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic).

Auroras are the result of disturbances in the magnetosphere caused by the solar wind. These disturbances are sometimes strong enough to alter the trajectories of charged particles in both solar wind and magnetospheric plasma. These particles, mainly electrons, and protons precipitate into the upper atmosphere (thermosphere/exosphere).