When's the last time you got a glimpse of the Milky Way? And if you're thinking of the candy bar, this hour's guest says that's a problem. "Dark sky" activists argue that in a 24/7 age, true darkness is increasingly rare, and light pollution threatens wildlife and our health. We'll talk about the social, legal, and natural pitfalls of constant illumination.

Guest:

Paul Bogard, author of The End of Night: Searching for Natural Darkness in an Age of Artificial Light