What are the Northern Lights?

The Northern Lights - or aurora borealis - appear as bright, swirling curtains of lights in the night sky and range in colour from green to pink and scarlet.

It is caused by charged particles from the sun hitting gases in the Earth's atmosphere.

The colours occur due to different gases in the Earth's atmosphere being energised by the charged particles.

The two most common gases in the Earth's atmosphere are nitrogen and oxygen. Oxygen atoms glow green - the colour most often seen in the Northern Lights, while nitrogen atoms emit purple, blue and pink.

The most impressive auroras occur when the Sun emits really large clouds of particles called "coronal mass ejections".