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Often described as natural fireworks, the Northern Lights
or Aurora Borealis most often take the form of streaks
of colours across the sky, and vary in colour from faint pastel
tones of greens, yellows and pinks, through to bright shades
of reds and golden yellows. They are an almost unique sight
in this world, though a similar mirroring effect occurs in
the southern hemisphere, called the Aurora Australis
seen at the South Pole and Southern New Zealand.
The science
This phenomenon is caused by solar winds - streams
of charged particles from the sun - reacting with magnetic
field around the poles, which is where it is at its strongest.
The solar wind puts a kind of pressure on the earth's magnetic
field, giving more energy to the particles on our own atmosphere,
and these in turn react with gas atoms in the upper atmosphere,
and release energy in the form of the coloured light that
we see. These auroral storms create an enormous amount of
electricity - the more energy produced the brighter the colours.
Where to see the Northern Lights
The lights can be seen anywhere in the North most part of
the Northern Hemisphere. Top places for sightings include
Arctic Canada, Alaska, Greenland, Siberia and even the Scottish
Highlands. However, the top place for Light spotting, because
of its accessability and milder climate, is Norway. The best
areas to see them are northern towns such as Tromso
and Alta, though beware of going too far north - from
Svalbard they are far less visible. North Norway is
the optimum site for Aurora spotting, with lights viewable
virtually every clear night. The best time for seeing the
full majesty of the Northern Lights is during the time of
the long polar nights, about October to March.
The extremes of the north have the added phenomenon of complete
darkness about three months in mid-winter, when the sun never
rises above the horizon, and the opposite in summer, when
the sun never sets. The whole of Norway sees the same phenomenon
to lesser degrees - winter visitors may often find the near-perpetual
darkness a little depressing, while summer visitors often
have difficulty sleeping, as the sun still shines through
most of the night.
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