When you fly overnight from Johannesburg to Europe the lights become thin just north of Lusaka, Zambia, a few more in Zambia’s Copper Belt and then nothing (and I mean nothing) until the North African coastline. For most of this 11-12 hour flight there are no artificial lights below. From the Sahara on south, but excluding South Africa, a region that is home to more than 400 million people consumes less electricity than New York City.
The World At Night (courtesy of Bert Christensen. Click to enlarge.)