Those beautiful light shows we occasionally see around the Wabash Valley are called auroras. At the North Pole, it’s called aurora borealis or northern lights. The South Pole, aurora australis or southern lights.
So how do auroras form?
Solar winds move toward the Earth emitting charged protons and electrons.
These particles follow Earth’s magnetic field.
The particles enter the atmosphere where the magnetic field is the weakest: the North and South poles.
The electrons begin colliding with various molecules in the atmosphere.
The resulting excitation of these collisions causes varying colors, based on the height and type of molecules hit.
Impacting with oxygen molecules makes for green. And you can see particles colliding with oxygen molecules at a higher altitude produces red. The same formula when collisions with nitrogen molecules occurs.
Auroras are not just something that happen on Earth. If a planet has an atmosphere and magnetic field, they probably have auroras. We’ve seen amazing auroras on Jupiter and Saturn.

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