The images came from the Suomi National Polar-orbiting Partnership satellite and they represent our most detailed look at Earth at night. Chances are you'll be able to spot your home town in these new images wherever it happens to be.
Here's a look at the whole globe:
And here is much of North America:
Most of this represents poorly directed, upward pointing light. It is essentially wasted energy.
These images do not document sky glow - that brightening of the night sky that keeps most of us from seeing faint stars and other sky phenomena. The best way to study sky glow is to measure it from down here on the ground. Thankfully it is easy to measure and document sky glow. A great and easy way for anyone to do so is to participate in the GLOBE at Night program. Be sure to check out their website to see how to get involved. Their first 2013 campaign begins on January 3rd!
Night sky brightness measurements from GLOBE at Night and other programs are an essential tool in documenting light pollution and I urge you to get out there and make some measurements.
The Black Marble - not so black, is it?