Do you recognize that song quote?  It’s from North to Alaska, by Johnny Horton, in 1960.  For most people raised in the Southeastern or Southwestern United States, that’s about as far to the aurorae as you ever came.  Of course, we know the aurorae are over the north and south polar regions, but for some reason many people only know them as the “Northern Lights”.  Those over the northern hemisphere are the Aurora Borealis, and those over the southern are the Aurora Australis.  “Aurora” was the name of the Roman goddess of dawn, “boreas” is Greek for “north wind”, and “australis” is Latin for “of the south”.

As an aside, the Aurora Australis was known to history before Australia (the continent), which was claimed and named in the 18th century.

Aurora Australis and Orion, 04/94, Image: NASA, STS-59 and Crew

The aurorae are caused by the Earth’s magnetosphere, which accelerates and funnels ionized particles along the magnetic field.  Aurora can be seen all over the world; indeed, it is imaged on other worlds, but it is more easily seen in the polar regions due to the magnetic field and longer periods of darkness.  Green or brownish red in the aurorae are associated with photons striking oxygen, while blue or red are associated with nitrogen.

Magnetosphere, Image: Science.NASA.gov

We know that the aurorae are caused by ordinary (and extraordinary) solar activity.  After the Carrington Event in 1859 (Saturday’s riddle) the aurorae were particularly active.  Reported all over the Earth, in some places they were so bright that one could read newsprint outside at 1:00 am.   Aurora Borealis and Aurora Australis are also believed to be nearly mirror images of each other.

Aurora Mirror Image, Credit: Polar VIS, NASA/JPL

Thought to be a sign from God to the Europeans in the Middle ages, the spirits dancing in the sky to the Cree, and the reflection of light from the body armor of virgin warriors by the Vikings, the aurorae have lost none of their beauty and appeal through discovery.

Here are a few links if you want to read more about the aurorae:

Aurora link RE: 1859 solar flare
Aurora forecast – Geophysical Institute
Sounds in and around Aurora
“The Northern Lights”, Alan Booth, 1992 documentary (45min)
The Northern Lights in mythology – Bullfinch’s, et al

And an excellent link to YouTube recording the sounds of aurorae, along with informational narration (well worth watching):

?Listening to Northern Lights, YouTube