The Northern Lights - level 3
The aurora borealis, also known as the Northern Lights. Residents in Minnesota in the US were able to see the light show shimmering in green and yellow. But how does it all happen?
The British Geological Survey says, occasionally, there are large explosions on the surface of the sun where huge amounts of charged particles are thrown out into space. These particles sometimes travel towards Earth, where they are captured by its magnetic field and guided towards the geomagnetic polar regions.
On their way down, these particles are slowed down by Earth's atmosphere, which acts as a shield. The charged particles collide with gas molecules in the atmosphere and the energy released is given off as light which can be seen in the aurora.
Under normal conditions, the northern oval lights cover Scandinavia, Greenland, Alaska, Canada and Russia and occasionally travel as far south as places like Minnesota.
Difficult words: resident (a person who resides – lives somewhere), shimmer (to shine with a soft light that looks as if it shakes a little), huge (very big).
Have you ever seen the Northern Lights?
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