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Northern Lights



Between September and March

 Nordic countries of Sweden, Norway, Finland, Greenland, Svalbard, Alaska, Canada and Russia

The Northern Lights occur when solar particles enter the Earth’s atmosphere and on impact emit burning gases that produce different coloured lights. The most common auroral color, a pale yellowish-green, is produced by oxygen molecules located about 60 miles above the earth. Rare, all-red auroras are produced by high-altitude oxygen, at heights of up to 200 miles. Nitrogen produces blue or purplish-red aurora. Pale green and pink are the most common.
The lights appear in many forms from patches or scattered clouds of light to streamers, arcs, rippling curtains or shooting rays that light up the sky with an eerie glow.
The scientific term for the lights is the aurora borealis (named after the Roman goddess of the dawn).
The bright dancing lights of the aurora are actually collisions between electrically charged particles from the sun that enter the earth's atmosphere. The lights are seen above the magnetic poles of the northern and southern hemispheres. They are known as 'Aurora borealis' in the north and 'Aurora australis' in the south.

The aurora borealis occurs in an oval doughnut-shaped area located above the magnetic pole. The best sightings are within the “doughnut” (rather than at the pole itself), and away from artificial light and moonlight.
The oval rotates with the sun, and it may grow and shrink in size considerably in only a matter of hours. The most spectacular displays occur in the northern parts of the following areas: the Nordic countries of Sweden, Norway, Finland (including all of Greenland and Svalbard), Alaska, Canada and Russia. Fainter displays of the lights can regularly be seen from Scotland. During periods of “solar maximum”, as now, they have been viewed from southern England.

Displays of the lights are notoriously unpredictable and cannot be forecast in advance. In the northern hemisphere, the aurora season runs from late September or early October to late March. The lights may be seen at any time during this period, but late October, November, February and March are the best bets.
Displays are governed by an 11-year cycle and are at their most dramatic during times of high solar activity (last one was 2013) but sightings can be recorded at any time. It is impossible to guarantee a viewing even during a period of “solar maximum”; if the sky is cloudy, the lights will be concealed.


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