Here's an interesting article on light pollution. I've been noticing this ever since I moved from a NY State suburb - with virtually no street lights, and thus no light pollution - to the Baltimore-Washington corridor (bathed in light 24x7). Back when I lived in NY, I could see lots of stars, and identify constellations. I noticed how bad things were in my area 2 years ago when my daughter was supposed to go out and look at stars - no identifiable constellations, and few enough that I almost thought I could count them! The article raises some interesting environmental and health concerns - and has some practical suggestions as well. Well worth a read.