Not quite. It’s the huge magnetic
field generated by charged
particles in the Earth’s molten
core.
What does it do?
As well as producing the
spectacular aurorae near the
poles and providing animals such
as migratory birds and sea turtles
with a means of navigating, it
also protects us from being
bombarded with radiation from
solar winds.
Hurrah for that. Anything else
I need to know?
The field has weakened by 15
per cent over the last 200 years.
Some scientists say this suggests
that Earth’s poles are about
to flip.
What? So north will be south
and south will be north?
Kind of. Compasses would point
south instead of north but it
would be a bit silly to rename the
hemispheres, wouldn’t it?
I guess. Should I be worried?
No. It’s happened many times in
the past and there’s no evidence
in the fossil record of a switch
causing any species to go
extinct. In any case, the poles
typically take several thousand
years to flip.
