by Bob Berman
I had just moved farther into the mountains in upstate New York, a solid 30 miles from the nearest large town or mall. Suddenly, the winter stars emerged with breathtaking clarity, as if someone turned up the contrast knob. I discovered, as we all do when vacationing or visiting friends in rural areas, that one price of twentieth-century technology is the diminishment of the night sky's beauty. It's hard to be enraptured by a few feeble stars poking through a synthetic, milky glow.
The culprit in changing the night from black to light gray (or, in major urban areas, to yellow orange or blue white depending on whether the streetlamps are sodium or mercury vapor) is artificial light, amazing amounts of which can be thrown into the heavens. One easy antidote is to aim the light downward rather than up toward the sky--mounting bulbs above billboards, for ...
