It’s also useful to keep an eye out at night on wildfires, weather (if the Moon is out to illuminate it), and other low-light phenomena.
For one thing, city lights map the spread of humanity, so over time we can measure how urban sprawl evolves. But when I look up at night and see my dark skies, I’m thankful for it.
It always amazes me how city lights in the United States just suddenly stop west of the central time zone. It’s amazing what you can pick out my favorites are the Nile River, Hawaii all by its lonesome in the Pacific, and of course my hometown of Boulder (and Denver). Images of city lights from Suomi NPP were mapped onto pre-existing data from the Blue Marble project to make realistic full-disk images of the Earth.
