The Northern Lights

The Northern Lights — or Aurora Borealis — are one of the most breathtaking natural light shows on Earth. Shimmering curtains of green, pink, purple, and red ripple silently across the night sky near the Arctic Circle. The same phenomenon happens near the South Pole too, where it is called the Aurora Australis. Together, the two are known as the polar lights.

The real cause begins with the Sun. The Sun constantly blows a stream of charged particles — mostly electrons and protons — called the solar wind. When this stream reaches Earth, our planet's magnetic field deflects most of it. But near the magnetic poles some particles funnel down into the upper atmosphere, where they collide with gas molecules and cause them to glow — exactly like the gas inside a neon sign.

Earth behaves like it has a giant bar magnet inside it, with magnetic poles near the North and South. This invisible magnetic field is actually a shield: it protects us from most of the Sun's harmful particles. The auroras are the beautiful, visible sign of that shield doing its job, channelling particles down towards the poles.