Aurora

ELI5 - What are the Northern Lights and what causes them?

The Sun, a colossal nuclear furnace, constantly ejects charged particles into space. These particles, carried by solar winds, traverse the vast expanse before encountering Earth's magnetic field.

This magnetic field acts as a protective barrier, deflecting most of the solar particles. However, at the Earth's poles, the magnetic field weakens, allowing some particles to penetrate the upper atmosphere.

Here, these charged particles collide with atmospheric gases, primarily oxygen and nitrogen. The energy from these collisions excites the gas molecules, causing them to release photons of light. This luminous phenomenon is what we observe as the aurora borealis, or Northern Lights. The colors, from green to red, are determined by the gases involved and the altitude of the interaction.

By Alex 4 months ago