You're watching FreeSchool!
The Cree called them the 'Dance of the Spirits.'
In Finland, they said the lights were caused by the firefox running so quickly across the
snow that his tail sent sparks into the sky.
Ancient Chinese observers believed they were the flames of good and evil dragons battling
in the heavens.
Even today, these mysterious and unpredictable lights are called 'Aurora,' after the Roman
goddess of the dawn.
An aurora, also known as a polar light, is a display of lights in the sky in the Arctic
and Antarctic regions, in an area known as the auroral zone.
An aurora around the North Pole is called 'aurora borealis' or the northern lights.
An aurora around the South Pole is called 'aurora australis,' or the southern lights.
They are usually greenish in color, but are sometimes blue, violet, pink, or even red.
Auroras constantly move and change shape.
Sometimes they are so dim they can be mistaken for clouds.
Other times they are bright enough to read by.
But what causes these amazing lights?
Auroras actually begin at the sun, which burns with so much energy that it superheats the
gasses around it.
Tiny particles, or pieces, of the sun are blasted away from it at speeds of over 450
miles or 750 kilometers per second.
This stream of particles is called the solar wind, and the Earth is directly in its path.
The solar wind can disrupt satellites and be harmful to astronauts in space, but the
earth is protected because of its magentic field.
The Earth has a molten iron core that rotates quickly, turning it into a giant magnet.
The magnetic field around the Earth is called the magnetosphere, and like a magnet, it has
a north pole and a south pole.
Most of the particles from the sun are deflected by the Earth's magnetosphere, but some make
it through to bombard the atmosphere.
As these electrically charged particles strike the atmosphere, they excite the oxygen and
nitrogen atoms, causing them to light up in the beautiful colors of an aurora.
If you want to see an aurora on earth, you should head to areas near the poles.
You may not know that auroras are also visible from space, where they can be seen as rings
around the north and south poles.
The earth is not the only planet to have auroras; they have been observed on Mars, Jupiter,
Saturn, Neptune, and Uranus as well.
Like the auroras on earth, auroras on other planets occur around their north and south poles.
Shifting curtains of light in the night sky, auroras have fascinated people for thousands
of years.
They are a visible reminder of the connection our earth has to the sun, and one of the most
beautiful phenomena in the heavens.
I hope you enjoyed learning about auroras today.
Goodbye till next time!