Light pollution at Paranal
Paranal is very dark, but there are some sources of light pollution we can’t do anything about. 80 miles north is the city of Antofagasta, which showed up more clearly than usual in this photo because of low cloud reflecting the street lights. And a similar distance up is the upper atmosphere, which glows faintly at night. Further afield, dust particles in the solar system reflect sunlight and cause the faint white band that stretches up from the horizon. The handle of the Plough is visible just above Antofagasta – a far northern constellation that we can just about see from down here.