A

A is for Aurora Borealis  (so it's not scary - I'm going for the sheer awesomeness with this one!)

An aurora is a natural light display, mainly in the Arctic & Antarctic regions, caused by the collision of charged particles within the high-altitude atmosphere.   In the northern latitudes, these are called the Northern Lights.  Aurora Borealis comes from the Roman Goddess of dawn, Aurora and the Greek name for the north wind, Boreas.

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