Two questions which arises in my mind about aurora borealis are:
From where did aurora borealis possess its irridescent colours?
Does aurora borealis produce sounds like thunder?
Answers:
Different elements that make up our upper atmosphere, give out different colours of light. The aurora borealis occurs high enough that the atoms in the atmosphere are sorted by weight, with the heavier atoms on the bottom and the lighter ones on top. The green and red we see most often is from atomic oxygen. the purple we sometimes see at the lower edge is where atomic nitrogen starts.
Well different studies have shown different things. But one study has shown that aurora borealis produce sound that is audible to human ear.
Note: These are the questions which arises in my mind only. It may differ from person to person.
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