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10 to 20 degrees from the magnetic
pole. Experts agree that because of
their location within the polar oval,
northern Norway and the archipelago
of Svalbard are among the best places
in the world to see the phenomena.
Named for the Roman goddess of
dawn by Galileo in the early seventeenth
century, the aurora is triggered
by solar wind, which brings charged
particles-known collectively as plasma-from
the sun. The magnetic fields
above the earth's atmosphere attract
the plasma. The lights appear when
high-energy ion particles from the sun
are trapped by the earth's magnetic field
and subsequently collide with atoms
and molecules in the earth's ionosphere,
some 100 kilometers and higher above
the earth's surface. Upon impact, the
energy that determined the
particles' velocity is released
into the atoms and the collisions
continue to occur with
the particles losing velocity
and the atoms absorbing
it. When the atoms can no
longer absorb energy, they
release their stored energy
as light. As the particles
continue to move down
more slowly toward the earth, more
collisions result in more emissions of
light from the atoms.
Though they occur from collisions
on the molecular level, the Northern
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