The Northern Lights are actually the result of collisions between
gaseous particles in the Earth's atmosphere with charged particles
released from the sun's atmosphere. Variations in colour are due to the
type of gas particles that are colliding. 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.
Northern Lights can be seen in the northern or southern hemisphere,
in an irregularly shaped oval centred over each magnetic pole. The
lights are known as 'Aurora borealis' in the north and 'Aurora
australis' in the south. Scientists have learned that in most instances
northern and southern auroras are mirror-like images that occur at the
same time, with similar shapes and colors.
Because the phenomena occurs near the magnetic poles, northern
lights have been seen as far south as New Orleans in the western
hemisphere, while similar locations in the east never experience the
mysterious lights. However the best places to watch the lights (in North
America) are in the northwestern parts of Canada, particularly the
Yukon, Nunavut, Northwest Territories and Alaska. Auroral displays can
also be seen over the southern tip of Greenland and Iceland, the
northern coast of Norway and over the coastal waters north of Siberia.
Southern auroras are not often seen as they are concentrated in a ring
around Antarctica and the southern Indian Ocean.
Auroral displays appear in many colours although pale green and pink are
the most common. Shades of red, yellow, green, blue, and violet have
been reported. 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
Hope this helps :)
Dec 7th, 2014
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