If you haven’t seen it, and want to, I’ll tell you how. Call your local astronomy club. Those geeks will go on and on about it, and put you on a list to be called if someone sees it happening. You have to agree to receive the call at anytime of night because this stuff is very unpredictable and may only last half an hour or so. Once you’ve had your fill, remember to get them to take your name off the list. Also remember to tell them what an awesome big microscope they have. Then, hmmm let’s see, what else… ask how far it can see, and if they have ever seen a UFO, and why none of the Big Dipper stars ever “shoot.”
Auroral activity strongly correlates with solar activity which peaks on an 11-year cycle. The story begins with the solar surface which continuously emits tiny charged particles such as protons and electrons. These particles are collectively known as the solar wind. The particles race through the solar system at 400 km/sec (about a million freakin’ miles per hour). They smash into the Earth’s magnetic field and are then suddenly off-ramped along the lines of magnetic force towards the Earth’s poles.
It’s a little more complicated by the fact that the Earth’s magnetic field is schmooshed by the solar wind on one side and squeezed, stretched, and stomped to hell on the other side. But finally the particles energize the atoms of rarefied gases in the upper atmosphere causing them to “fluoresce” with lovely colors. You know how florescent light tubes work? Of course you do. Well it’s kind of the same thing except with florescent light tubes you can throw them and they make a satisfying popping sound when they implode. Meanwhile you pretend that you are Odin or some shit.
Aurora Borealis (northern lights) and Aurora Australis (southern lights) are coming from way up in the atmosphere, about 100 to 120 km up. That’s pretty high. But a few are even higher, some more than 500 km. They are mostly intense in big rings around the north and south poles known as the “aurora ovals” which range roughly from 12 to 23 degrees from the magnetic poles of the Earth. The ovals are largest on the night side of Earth and smallest on the day side, hence forming rather crappy oval shapes.
There are several terms that starhoppers use to describe the various special effects.
- Arc: (like the sound made by a surprised duck) a soft slightly curved shape like a big feather.
- Band: an irregular shape with kinks or folds, like The Rolling Stones.
- Break Out: sudden burst of activity across a large area of the sky.
- Curtain: folds of drapery that drape around like a draping of drapes.
- Flaming: liberal bursts of light appearing at the base then rapidly moving up and disappearing at the top.
- Flickering: pulsating fast, about 5-10 times per second.
- Patch: region resembling a cloud of smoke, but in patch form to help you quit.
- Picket Fence: a whole bunch of rays in a row in front of your yard.
- Pulsating: brightness alternating in a slow hypnotic manner.
- Ray: like a picket fence with only one picket, aligned with Earth’s magnetic field.
- Quiet: uniform intensity that glows over a long period of time (minutes) without saying much.
- Veil: a very large area of uniform brightness, like a bride whose face is replaced by a 40 watt light bulb.
Auroral brightness is rated on a scale ranging from 0 to 4, with 0 being a barely visible this is stupid why did you call me, and 4 being a very bright, tear-jerking, what-does-it-all-mean, break-dancing, in-your-face, can I borrow a towel, auroragasm.
The colors are typically kiwi and magenta but they can cover the entire spectrum. On rare occasions sounds are reported, such as hissing, swishing, rustling or crackling. I once heard snickering but that might have been my date.
The name “Aurora” was given to the events by Galileo. It refers to a character from Roman mythology, the herald of the dawn (Eos to the Greeks). She is known for asking Jupiter to make her husband immortal but forgot to add “and he stays young” so he lives forever but as an increasingly decrepit raisin in a wheelchair or something. The lesson learned? Jupiter is an asshole.
Myths and legends are a big deal in naming astronomical stuff. Here are some legends from a few northern native tribes in the Americas describing what the lights of the aurora really are.
Kwakiutl: Dancing spirits, especially those of deer, seals, salmon and Beluga whales. Let me tell you, those Belugas can really cut a rug.
Fox: The ghosts of slain enemies who are restless for revenge. They are trying to rise from the dead and attack. Probably upset about something they saw on Fox News.
Inuit: Spirits of dead humans playing ball with a walrus skull.
Nunivak: Spirits of dead walruses playing ball with a human skull.
Ammassalik: The dancing spirits of dead babies. The dead babies dance around in circles which you have to admit is cray cray totes adorbs.
Algonquin: Nanahbozho (the creator) traveled to the north and built a large fire, of which the aurora is reflections in the clouds. Even gods get cold I’m guessing, since the gods of northern cultures are often depicted wearing heavy coats.
Menominee: Torches used by friendly giants in the north, to attract fish that they spear. The giants are quite friendly and everyone wants to meet them, except the fish.
Mandan: Fires over which the warriors of northern nations simmer their dead enemies in enormous pots (skip the soup, fill up on bread).
Makah: A tribe of dwarves (half the length of a canoe paddle but so strong they catch whales with their bare hands) boil blubber over fires. Apparently whale blubber builds strong muscles, but stunts your growth.