Satellite images of Earth at night have been a curiosity for the public and a tool of fundamental research for at least 25 years. They have provided a broad, beautiful picture, showing how humans have shaped the planet and lit up the darkness.
Astronauts are taught to concentrate on the shapes of coastlines for a visual cue about where they are when circling the planet. The nose of Cape Karmel and the bay that protects Haifa are shapes that stand out.
Satellites detect increases in lighting around the holidays, particularly in suburbs and rural areas. While the trend says interesting things about culture, it also tells us something important about energy use.