What is Aurora?



Auroras are the spectacular dancing lights that mostly happen around the poles. Surprisingly, they are caused by the sun’s solar rays. Probably you already know the magnetosphere that protects us from the sun’s harmful rays. There are cracks in the magnetic fields on the poles that produce auroras. But how do the auroras get their color?

Air is made of nitrogen (79%) and oxygen (20%). Oxygen glows yellow-green when hit low in the atmosphere and orange higher up. Nitrogen glows bright red when hit normally, and bright blue when ionized.

A halo of light always exists over each pole. Though, they are too faint to see. They are only seen clearly when extra bursts of energy from the Sun come to Earth. The stronger auroras are only produced when Coronal Mass Ejections (CME) are released by the sun.

The nearer you are to the poles, the more aurora displays you see every year. For example, New York and Edinburgh are having an average amount of 10 aurora displays every year.

Thank you!-Nat

Picture credit : NASA

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