You might have assumed that the northern lights were caused by the interaction of charged particles from the sun with atoms in the upper atmosphere.  But auroras were actually the world's first greeting cards.  "Say it with auroras."  From Manchester College's 1920 yearbook.

"The gate in the sky."  From Adventure magazine, 1922.

A comet cuts through the aurora.  From A Revolution in the Science of Cosmology by George Campbell, 1902.

Aurora skates with polar bears at the North Pole.  From Harper's Young People, 1887.

Northern lights from London Bridge.  From Popular Mechanics, 1927.

Here's the Aurora Borealis from Strange Yet True by James Macaulay, 1892.  Some other vintage auroras are here, here, here, here and here.

Here's the north pole as a barber pole, from Discovery of the North Pole by J. Martin Miller, 1909.

"The Aurora Borealis, with a reindeer-drawn sledge in the foreground."  Coloured wood engraving by C. Whymper.

Here's an unusual appearance of the Aurora Borealis, as obvserved by Captain Parry in his expedition to the Arctic regions, from the Encyclopedia of Natural and Artificial Wonders and Curiosities by John Platts, 1876.  (We previously discovered other precursors to If You're Afraid of the Dark, Remember the Night Rainbow, which we showcased here and also here.)

From The Bells by John Jordan Douglass, 1920.