US Army has used low light detectors for 40 years now and today we can see such data with the Suomi NPP satellite, which can detect the light a single ship in the ocean. I didn’t believed that we send so much light into space until I saw the breathtaking video of Earth’s Countries.
You can see geographical and political divisions just by looking at the lights. An extreme example is North and South Korea. Just look at the real darkness from there.
Enjoy the wonders of our technology.