Page 178 - (DK Eyewitness) Travel Guide 2017 - Alaska

176  ALASK A AREA B Y AREA

The Aurora Borealis

The Fairbanks area is one of the best places in the world to see the aurora borealis, or
northern lights. The effect is visible as faint green, light yellow, or rose curtains, pillars,
pinwheels, wisps, and haloes of undulating, vibrating light. During the greatest auroral
storms, it appears as bright yellow, crimson, or violet streaks of light across the sky. While
summer visitors will miss out due to the 24-hour daylight, there is a good chance of
catching the celestial show on clear nights between late September and early April.
Indigenous peoples had various explanations for these dancing lights. One legend
said that they were the spirits of their ancestors, while another held that they were
past and future events playing out across the sky.
Auroral undulations are due
to the eddies, fluctuations, and
directional changes in the earth’s
magnetic field. During a single
storm, the aurora can produce
up to a trillion watts of electricity
with a million-amp current. Some
people claim that they can hear
the aurora crack ling and whirring,
or feel its charged particles,
although scientists doubt this.

The Northern Lights Phenomenon
The aurora is caused by the interaction of the Earth’s
magnetic field with charged particles from the sun. As the
sun fuses hydrogen into helium, it emits particles of radiation
– protons and electrons – that are shot into space. When this
plasma stream of particles, known as the solar wind, blows
past the earth, the earth’s lines of magnetism draw them
toward the points where these lines converge, at the north
and south magnetic poles. As the particles arrive in the
ionosphere, they collide with gas atoms, causing them to
emit light. The type of gas determines the color of the aurora. Rare crimson aurora borealis over spruce
and birch trees, Fairbanks

Vivid green aurora borealis shining above Bear Lake on Eielson Air Force Base

For hotels and restaurants in this area see p244 and pp254–5

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