On Tue, 21 Sep 1999 you wrote:

> I would like information about the Northern Lights. I have often seen them
> in Michigan but not in California and the west. I am interested in knowing
> what they are, and what causes them to appear, etc. Also any related stories

Hello,

The aurora, also known as the Northern Lights, are the result of Earth's
magnetic field interacting with energetic particles from space. These
particles, many of which come from the sun, are funneled by the magnetic
field to the Earth's magnetic poles. The north magnetic pole is located in
northern Canada, and so these particles hit the atmosphere around that
part of the Earth. When the particles hit the atoms of the atmosphere,
the atoms get energized and glow, much like the atoms inside a neon lamp
or a flourescent light. As the incoming particles change, and the
atmosphere changes, the colors and patterns we see in the sky change, too.

Because the aurora are caused by particles hitting the atmosphere near the
Earth's magnetic poles, the further you live from the pole, the less
likely you are to see the aurora. For this reason, people who live in
Alaska, Canada, and the northern states of the continental U.S. can see
the light display fairly often. Those of us who live further south only
see the aurora on very, very rare occassions when a massive magnetic storm
occurs.

You can read more about the aurora at the Aurora Page,
http://www.geo.mtu.edu/weather/aurora/
You can see a current picture of the "auroral oval", the region where the
aurora are currently visible, at
http://sec.noaa.gov/pmap/index.html
Similar information is available at the University of Alaska's page:
http://www.pfrr.alaska.edu/~pfrr/AURORA/

Some of the stories and legends of the aurora can be found at:
http://athena.wednet.edu/curric/space/aurora/aurfolk.html
and
http://www.yukon.net/Community/FHCollins/Carrie/folklore.html

Thanks for writing!

Sincerely,
Kurtis Williams

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