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Northern Lights | 
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Northern lights occur very high above the Earth, usually over 40 miles high, even higher than jet planes fly.
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The Northern Lights, or 'Aurora Borealis', are a natural light show that can be seen at the North Pole. They also occurs at the South Pole, where they are called the 'Southern Lights' or 'Aurora Australis'. They are a spectacular display of different shades and colours of light rapidly moving in the night sky. The solar wind is very closely linked to the 11 year solar sunspot cycle and solar flares.
The lights occur when particles from the sun interact with the Earth's atmosphere. These particles are what's known as 'solar wind', and are quickly moving charged particles that are emitted from the Sun. The solar wind is very closely linked to the 11 year solar sunspot cycle and to solar flares. Most of the world is protected from these particles by the magnetic field of the earth, except the Poles. Here the solar wind can interact with the Earth's atmosphere.
When the charged particles collide with the Earth's air molecules, their energy is emitted as light. As the solar wind only interacts with the air at the Poles, this is where we see the lights, in a ring around the Poles called the 'auroral ovals'. When there are more particles travelling from the sun, the ring expands and northern lights have been reported in the UK. They are more common in the north of Scotland, as it is further north. The lights occur very high above the Earth, usually over 40 miles high. This is even higher than jet planes fly, but the lights have been seen as high as 600 miles above Earth, which is even higher than space shuttles fly. The solar wind can also have an effect on our telecommunications. Many radio signals are 'bounced' around the Earth using the top of the atmosphere. The charged particles of the solar wind disturb parts of the atmosphere, which causes interference. ...weather forecasts were predicted using the aurora.
Long ago, weather forecasts were predicted using the aurora. Countries could not agree on what they indicated though. In Greenland they were believed to forecast storms, but elsewhere they were believed to foretell fine weather. We now use more sophisticated methods of forecasting weather, but the there is some indication that the overall climate may have some link with the amount of aurora activity.
The Earth is not alone in experiencing this light show. Aurora have also been reported on Jupiter, it just seems a waste that no one is able to witness it! | |||||
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