The aurora borealis, or Northern Lights, has fascinated men for centuries. It is an
amorphous pink glow or light arch of color in the northern night sky. On the other side
of the earth, in the high latitudes of the southern hemisphere, the aurora australis
dances across the dark skies in a similar show. An aurora’s light is created when oxygen
and nitrogen atoms and molecules collide with charged solar particles. The different
colors of the phenomenon appear at different altitudes. For example, red light is
usually seen 120 miles or more above the ground. Below this the light is green, and in
the lowest region, about fifty or sixty miles above the earth, the light is purplish.
At times, an especially large surge of electrically charged particles escapes from the
sun, an event occurring periodically during sunspot cycles. Then, the usually
light-colored auroras erupt in a magnificent display of light and color near the poles.
One witness, on relating his account of the event, remembers seeing first a flicker,
then a glow that reached halfway across the sky. The light grew brighter and redder,
like fire. Purple and green light rippled out, and soon giant folds began to make waves
like silk stirred by wind.