Page 81 - (DK) I Can’t Believe It! 2

STRANGE BUT TRUE! 79

Auroras occur when the solar wind—electrically charged particles escaping
the Sun—becomes trapped by Earth’s magnetic field. The particles are
funneled toward Earth’s two poles, colliding with gases in the
atmosphere. These collisions produce Aurora borealis at
the north magnetic pole, around the Arctic Circle, and
Aurora australis at the south magnetic pole, around
the Antarctic Circle.
FAST FACTS
Solar wind

Aurora
borealis
Sun
Aurora
australis
Magnetosphere
Earth’s magnetic field forms
a protective layer around the
planet. Called the magnetosphere,
this deflects most of the solar
wind particles. The particles that
penetrate the magnetosphere are
channeled toward the north and
south magnetic poles. There, they
interact with atmospheric gases
to create brightly colored auroras.
An electron Electrons enter Earth’s
hits an oxygen upper atmosphere.
atom, making Above 400
it glow red. miles (640 km)

Atom
When a nitrogen
atom is hit by Oxygen atoms
an electron, glow green when
it glows blue. electrons strike.
Molecule
A nitrogen
molecule glows
crimson when Below 62 miles
In the past, it is struck. (100 km)
auroras were As electrons enter Earth’s upper
considered a atmosphere, they meet atoms of
premonition oxygen and nitrogen at altitudes
of war or high above Earth’s surface. The
color of the aurora depends on
plague. which atom is struck, and the
altitude of the meeting.

US_078-079_309600_Light_show.indd 79 10/01/18 2:57 pm