Frivolous Names and Scientific Labels: Pretty Pretty Lights Edition

To continue last Monday’s discussion on names, scientists get a bad rap for not being creative.  Richard Feynman, a Nobel Prize-winning physicist once told the following story:

Feynman went on to explain that as a scientist his idea of the aesthetic beauty of a flower could go even deeper than that of his friend, because he could appreciate how the beauty had a purpose, could be amazed at how it fit together on a more intricate and simpler level, and how understanding how something work only adds to the enjoyment of life and everything in it.  But the stereotype still holds, most people expect scientists to be a little more concrete than the average person on the street, and definitely less prone to flights of fancy.   

Which is why it’s absolutely wonderful when you start researching upper-atmospheric lighting (also called transient luminous events).  Not because of what it is on its own (although that’s pretty nifty too), but because of the names- the scientific official names- that are given to these phenomenon.  The terms?  Red sprites, blue jets, elves, gnomes, trolls and pixies. 

That’s right.  Sprites.  

Now technically the terms came about because when researchers at the University of Alaska in the 1990’s observed them they had no idea what they were. 

Not knowing what they were, whether they were electrical, magnetic, or whatever, left them in a bind.  They couldn’t give them a technical term to these beautiful displays because they didn’t have a definition for them.  Calling them by a nonsensical name (after the mischievous spirit Puck from Shakespeare’s A Midsummer Night’s Dream) solved the dilemma until they could figure out what caused them and the names just stuck. 

And once a frivolous naming tradition is established you simply have to follow through, right?  Thus when a new phenomena was observed they came up with a wonderful acronym: Emissions of Light and Very Low Frequency Perturbations from Electromagnetic Pulse Sources.  Or Elves- if you lose the second L.  And the F.  And the P.  And the other P. 

Does it even count as a proper acronym at that point?

But at least that acronym gives us an idea of what they are.  Transient luminous events (TLEs) are similar to lighting, but occur in the upper atmosphere- most particular the ionosphere.  

It appears that thunderstorms discharge electrical energy upwards as well as groundward, and that TLE’s are the result.  Sprites are the most common, and appear for a very brief moment in the air above a thunderstorm directly after a positive ground-to-earth lightning strike. Sometimes they can extend nearly 60 miles past the top of the cloud. 

Blue jets project from the top of the thunderhead, usually in a narrow cone about 25-30 miles above the top of the cloud, but are harder to spot from the ground based on their size and the fact that blue light doesn’t travel as well as red.  Strangely enough, blue jets aren’t associated with lightning strikes the way red elves are, but they do seem to appear when thunderstorms have strong hail activity.  Elves are similar, but appear as a dim, flattened glow that expands like a halo. 

They really aren’t that rare (the Formosat-2 satellite has observed several million TLEs a year), but-excepting red sprites- are difficult to observe properly from the ground.  Most of our studies of the phenomenon have been from the air, either shuttle observations of the earth or from special research flights.

But because of the prohibitive expense of such flights we really don’t know much about them.  It’s suspected that TLEs are the cause of several high altitude unexplained accidents, and they’ve probably fueled their share of UFO sightings.  But they’re only all the more interesting for being unexplained. 

And for proving once and for all that scientists have a sense of humor too. 

 Here’s a video of some sprites and jets in action.