Nature’s Neon Light Show
Finland is a country of great natural beauty: It’s covered in forests, has over 50,000 lakes, thousands of islands, and crisp, snowy landscapes. It is also one of the best places in the world to see nature’s most awesome light show, the Aurora Borealis.
The Aurora Borealis or Northern Lights) is seen in countries in the far North of the world. In the far South, it is known as the Aurora Australis or Southern Lights. It is more colourful and easier to see closer to the earth’s magnetic poles.
It often starts off in the evening as an arc of light. Sometimes the colours are pale and smoky, other times very bright. They move and shimmer as if blown by the wind. The most amazing sight is when they appear as curtains of green light with a pink edge, rippling across the sky. The curtains of light can stretch almost across the entire sky.
The lights can reach from 80 to 640km above the surface of the earth. The most common colour is neon green, but they also appear in red, blue and violet. Sometimes, just after midnight, the colours turn on and off as if someone was flicking a giant light switch. They can only be seen in darkness; so as the sun comes up at dawn, the colours disappear.
There are many myths and stories about the Aurora. In Finland it is known as “revontulet” which means “fox fires.” In the old days, people believed that the lights were caused by an Arctic fox running so fast through the snow that his bushy tail flicked sparks of colour up into the sky. Another belief was that the lights were caused by fish scales gleaming in the Arctic sea and reflecting into the sky. In some parts of the world, it was thought that the lights were the fire of a dragon’s breath!
Scientists now know that the Aurora is caused by solar winds coming from the sun. The solar winds are full of particles which are drawn towards the earth’s magnetic poles. They get trapped in the earth’s invisible magnetic field. When the particles escape and hit gases from the earth’s upper atmosphere, the Aurora appears in the sky.
Over the centuries, people have said that the Aurora sometimes makes a sound – hissing and crackling, like a flag flapping in the wind. The ancient Sami people of the Arctic Circle called the Aurora “guovssahas” meaning “the light which can be heard.” In 2012, scientists from Finland recorded the sound – but how the sound is made is still a mystery.
The Aurora is most often seen from late September through to early March. The best time to see the lights is on a dark, cloudless night, out in the countryside away from streetlights. They can happen at any time of night, but they most often occur around midnight. In Finland the weather service puts out an aurora watch so that you can tell if an aurora is likely.
