THE SOUTHWORTH PLANETARIUM

207-780-4249   www.usm.maine.edu/planet

70 Falmouth Street   Portland, Maine 04103

43.6667° N                   70.2667° W 

Altitude:  10 feet below sea level

Founded January 1970
Julian Date: 245906.16

2019-2020:  CV

            "As we were saying..."

THE DAILY ASTRONOMER

Wednesday, February 26, 2020

Exit Sign Astronomy

And then we saw the Exit signs.

You know those signs:   ubiquitous, yet unobtrusive.  They are the Banquo's ghost of the modern age: lurking in the corners and corridors of buildings across the world.    Guiding us all without imposing their presence on us.  We pay them little mind unless poison gas, mephitic fumes or some other menace insinuates itself onto our personal space.  Then we look for them as a desperate wretch seeks out a sagacious guru.    

Our subterranean star dome theater contains two such signs, one for each exit, as one would expect.   Be it in the middle of the day amidst the teeming throng of patrons or in the deep of night accompanied only by the unearthly entities that populate dark empty spaces, the two red exit signs have stood as sentinels in their place since the planetarium hatched out of the seafoam of Paphos.   Like red dwarf stars with life spans exceeding a trillion years, theirs is a perpetual light destined to remain luminous even when the rest of society perishes in a sudden conflagration (November 3, 2020.  Don't forget to vote.)

And then we saw the Exit signs.

Green.   Beautifully bright,  drop dead gorgeous vibrant green reminiscent of dew-moistened shamrocks and a youth overflowing with promise.  WHAT?!  The exit signs were changed, in accordance to the rules inscribed on the most recent slab of blue sapphire to have descended out of the highest cumulonimbus.  Granted, the other signs were a bit worse for wear after having exuded their feeble light for the better part of a half century.   In fact, the "t" in the one marking the south door was almost wholly obscured and since none of us could figure out what EXI next to a door could possibly have meant, it is fortunate that the change occurred.

And then we saw the star field.

Las Vegas

Oh, crumb.

While those beguilingly pretty exit lights imparted a pleasingly numinous glow onto the star dome, the stars themselves were difficult to observe.  And, well, yes, that does sort of defeat the purpose of a planetarium, doesn't it?  

Hmmm...

Well, we can certainly explain the problem.   The problem is with the color.    The previous exit sign glowed red which, while admittedly unimpressive, is still wonderfully monochromatic.  In those observatories where people still actually look through telescopes red light illuminates the interior.   Such light allows observers to scrutinize star charts without impairing their dark adaptation.     People who venture outside to see the night sky will often take a red flashlight to illuminate their own charts for precisely the same reason.       If you take out a green light, you might as well not even bother.

Green is the astronomer's enemy, hence the status of their bank accounts.

All the same, we loved the green light from the first moment! Not only was it pleasing to the eye, it engendered a sense of exuberant joy and imperturbable serenity in us...well, when we weren't cursing about it.    Realize that we are all descended from countless generations of adamant sun worshippers.  Our ancestors revelled in the searing sunlight that scorched the savannah and filtered through forest canopies. We still yearn to be near such light, despite the unalloyed bliss we all experience having evolved to the point where we're now cloistered in cubicles under pervasive fluorescent lights.    

 The Sun's maximum light output is in the green part of the spectrum: between 483 - 520 nanometers.   A light that was similar to the emerald glow that washed tsunami-like over every nook, cranny and crevice in our underground Universe.  The Sun was in the planetarium!

No wonder we were all so damn happy.

Fortunately, we explained our predicament to the two ingratiatingly pleasant associates who installed the exit signs.   They managed to persuade the powers that be to allow us to have red exit signs again, albeit brighter ones that illuminate all the letters.     I am admiring them right now: the signs, not the associates, that is.   Both brighter red, but not blindingly so.  The dancing, bubbly extroverted cousins to the timid, unassuming red exit signs that chewed their fingernails and read stoic philosophy for pleasure.  

The starfield is restored.

The exits are well marked.

The planetarium can now persist after having survived its latest existential crisis.     Despite these tribulations, we'll miss the green light.  In fact, we'll always remember that week in which the green exit signs cast their verdant luster into our underground chamber.      We know that those green exit sign days will always remain phantom like in the space-time matrix, metaphysically extant but irretrievable, thank heavens.

Also, it demonstrates that in a world that allows for all possibilities and in which all things can contribute a verse in this powerful play,  every so often even something as peripheral as an exit sign can suddenly find itself in the focal point of our attention.  Perhaps another fifty years will elapse before we put the exit signs in the spotlight again.  One can only hope.

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