The original blue LED's

The sun is setting here in Tennessee tonight.   It's a pale yellow streaked with magenta on the edge of the horizon.   As usual, I'm in the airport.  I'm looking out over the tarmacs and runways.   And, as it slowly gets darker, I can start to see tiny electric blue lights pop into existence. 

The blue lights become brighter as the dusk disappears, and form virtual paths that guide planes like customers walking up the aisle in a dark movie theatre. 

These are special lights, airport or not.  They are the original blue LED's.

We first saw them on trips in the family station wagon as we passed O'Hare airport.  On just the right part of 294 - and if you were sitting on the good side of the car - you'd get a 10-second glimpse of the airport from its Eastern edge. 

Of course, it only worked at night.   We couldn't really see any planes in the dark from that distance.  But what made that brief sight so cool were the twinkling blue lights.   Intense neon pinpoints of sapphire and cobalt, they stretched in lines and patterns until they flickered out in the distance.