When teachers guide students in gaining awareness that industrial agriculture writ large, for example, results in chemical runoff from nitrogen-based fertiliers in the Mississippi River that in turn creates a massive dead zone in the Gulf of Mexico so large that it is visible to the human eye through satellite distant imaging, students are able to grasp the basis for sustainable agriculture.
The pictures come from the Visible Infrared Imaging Radiometer Suite (VIIRS) satellite, and have been referred to as "The Black Marble" in reference to the famous "Blue Marble" daylight pictures.