The Northern Lights : Facts and Causes
What are the Northern Lights?
If you take a trip to the Arctic region, in the Northern hemisphere you are likely to see a natural colourful display in the sky. This is known as the Aurora Borealis, which is Latin for Northern dawn.
What causes the Northern Lights?
- These colourful lights are the result of interactions between solar storms from the sun and the earth’s outer atmosphere. During the day solar storms from the sun blow an array of particles, called solar winds.
- The solar wind is like a burp given out by the sun from time to time. The earth comes in between the path of these solar wind particles. These particles are filled with energy. Many electrons and protons from these particles get trapped in the polar regions of the Earth.
- The Earth’s atmosphere is made up of two main gases, oxygen and nitrogen. These electrons and protons from the solar winds, full of energy, collide with the oxygen and nitrogen atoms in the Earth’s atmosphere and they become electrically charged. This charging produces a display of lights in the sky- the Aurora Borealis.
6 Amazing Facts about the Aurora Borealis
- The Aurora Borealis have been happening since ancient times. The earliest account can be found on a Babylonian clay tablet dating back to 567 B.C.
- They can either be static or travelling lights and can occur up to 1000 kilometres. Most auroras occur at a height of 80+ kilometres above the earth! They can last for a few minutes to several hours.
- The aurora can be of a variety of colours- red, green, brown, blue or a burst of colours together.
- The oxygen molecules in the earth’s atmosphere are responsible for the green or brownish colours while the nitrogen molecules are responsible for the blue or red colours.
- Show in image. Do an exercise around this- show an aurora with green and blue colours and ask why is it blue or green? Answer- oxygen molecules make it green and nitrogen molecules make it red.
- Auroras occur usually around ring shaped regions, so they are seen around the two poles. They have also been spotted on planets like Jupiter and Saturn.
For more such Geography articles and videos, visit: http://mocomi.com/learn/geography/