There’s no research suggesting that light is a public health crisis, Barentine said. “It’s interesting, and it appears to be suggestive, but it’s not conclusive.” Nevertheless, he made grand comparisons, hoping that the dark-sky movement could create and benefit from sweeping changes in public opinion, much like the same-sex marriage movement or antismoking campaigns. (The research gets even more conflicted when you consider the benefits of light, which, in big cities especially, is often thought to deter crime.)
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At times, though, Barentine sounded more like an evangelical darkness missionary, invoking the importance of our dimming heritage. “Human beings could use a little bit of humility now and then,” he said. “Does it add something, like art or literature or music? I’m convinced it does.”