Lot's of people enjoy fireworks, whether it's 5th November or
Thanksgiving, Chinese New Year or Duwali.
But nature won't be outdone and, thanks to Earth's magnetic
field and furious explosions of energy from our sun, we have the
northern lights.
The northern lights look like a shimmering curtain of glowing
colours, dancing across the night sky. Normally, they are seen
above the arctic circle, in places like Norway. Their proper name
is "aurora borealis", which is
Latin for "northern dawn".
In the south, above the Antarctic, you can see the southern
lights. They are called "aurora australis".
Have a look at this video of the northern lights. What do you
think causes them? Find out after the video!
What causes the northern
lights?
Every day, solar storms tear across the surface of the Sun.
These solar storms blow a stream of particles towards Earth, called
the solar wind. The particles in the solar wind
have lots of energy.
The energetic solar wind particles collide with the Earth's
atmosphere and hit oxygen and nitrogen atoms. Some of the energy
from the particles in the solar wind gets passed to the oxygen and
nitrogen atoms. This makes the oxygen and nitrogen atoms glow
different colours.
The result is an amazing explosion that fills the sky. The
photo below, taken in Iceland, is a great display. It even
includes a shooting star for good measure!
A spectacular display of
Northern Lights over Oraefajokull in
eastern Iceland (c) E. Sigurmundsson (LocalGuide.is)
When can you see them?
The Earth's magnetic field pushes most of the solar wind
particles to the north and south poles. This is why the best place
to see the northern lights is in the arctic.
Sometimes the Sun becomes very active and sends out even more
energetic solar wind particles. This is when people in the UK can
see the northern lights (although only if it is a clear night).
People in Scotland have the best chance.
Solar storms are sometimes reported on the news, or you can look
at websites like Aurora Watch to find
out when one might be on it's way.
Try and get to a dark place away from street lights, so ask a
grown up to go with you. This is the best place to see stars and to
look out for the best fireworks display in the solar system!