The Northern Lights, or aurora borealis, happen when charged particles from the Sun interact with Earth's atmosphere near the polar regions. The basic sequence is sun emits streams of charged particles (the solar wind and occasional coronal mass ejections). These particles travel through space and are mostly deflected by Earth’s magnetosphere, but some are guided along magnetic field lines toward the poles. When they collide with gases (primarily oxygen and nitrogen) high in the atmosphere, the gas atoms become excited and then release energy as visible light, creating the shimmering curtains, rays, and swirls you see in the night sky. The color depends on the type of gas and its altitude: green is most common (oxygen around 100–300 km), red can appear from higher oxygen emissions, and purples/pinks can involve nitrogen and other excited states. The activity is stronger during times of increased solar activity, such as solar flares and coronal mass ejections, and is more easily observed in dark, clear skies away from light pollution near the magnetic poles. Key points:

• Source: solar wind particles (electrons and protons) from the Sun.
• Mechanism: particles collide with atmospheric gases and excite them, emitting light.
• Location: most visible in high-latitude regions around the Arctic and Antarctic.
• Color varies by gas and altitude; most common is green, with other colors possible.
• Timing: influenced by solar activity; auroras often follow solar storms by a day or two.