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Archive | Light Pollution

Conflicted by Light

As an Astronomer, I am very pro-dark sky. As a person in favor of migrating birds, baby sea turtles, and general good health, I’m anti-light pollution. As a human who wants to see our planet’s environmental crash slow down and reverse, I’m in favor of energy conservation. Generally, these three sets of opinionated voices in my head work in tandem to encourage people to use down-pointed lights that contain orange-ish low-pressure sodium lamps. When those don’t work, I turn to the web site of the International Dark-Sky Association (IDA) where they list lighting, even Antique Street Lamps that would match my historic neighborhood’s idea of good landscaping. Unfortunately, a new light on the block is going to bring conflict to the normally collaborative voices. That new light is the ulta-luminous white LED. Taking 63 watts to produce 8500 lux, and lasting roughly 30 years, these brand new lights are every energy savers dream come true. Municipalities are considering switching to this new new tech toy to save city resources. Unfortunately, white LEDs (see image left, credit: CREE lighting) are every dark sky dreamer’s worst nightmare.

In Search of Darkness

IC 342Star light, star bright, first star I see tonight…First star? Hello? You’re supposed to come out now. Stars? Someone? Shine? Please?

While I was a graduate student at the University of Texas in Austin I watched the Ring Nebula (M57) disappear. When I first arrived in 1996, this former stellar atmosphere was clearly visible in binoculars from the roof of the building I worked in (RLM). In 2000 I could no longer see it, but some of my more owl-eyed students could see it faintly contrasting against the background glow of too many city lights. When I graduated in 2002, it was just gone. No pair of 10×50 binoculars was going to find it. According to the Greater Austin Chamber of Commerce the city grew from 846,227 people in 1990 to 1,452,529 people in 2005. With that growth came lights, and with those lights came star consuming light pollution. As the world population grows and becomes progressively more industrialized, our entire planet is losing its ability to see faint stars and galaxies in the night skies.