nightside auroral oval
Quick Summary
The nightside auroral oval is a region in Earth's atmosphere where auroras, or the Northern and Southern Lights, are most frequently observed. These spectacular light displays are caused by charged particles from the Sun, primarily electrons and protons carried by the solar wind, interacting with Earth's magnetic field.12
These high-energy particles are guided by magnetic field lines towards the planet's magnetic poles. When they collide with atoms of nitrogen and oxygen in the atmosphere, they excite these atoms, causing them to emit light. Oxygen collisions produce red or green light, while nitrogen collisions can result in green and purple hues. The auroral oval is centered a few degrees towards the nightside of the geomagnetic pole, and its size and location can shift depending on solar activity.12
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