The Mexican-American border separates the cities of Ciudad Juarez, Mexico with El Paso in Texas, USA. This image shows both cities at night, as pictured by an astronaut on the International Space Station circling Earth at around 400 km above.
From space, political borders are not visible but subtle differences in street-lighting can be revealing. In this image the international border between the cities is brightly-lit corresponding to the thick yellow line dividing the mass of lights. North of the border is El Paso with its well-illuminated major motorways such as the straight US Route 180 leading to the east. Just to the north of El Paso is Biggs Army Airfield that shows up as remarkably different to the residential areas and city centre of the town.
The city of Ciudad Juarez shows a different layout to its US sister city. Juarez is more densely illuminated and roads stand out less visibly. One exception is the ring road Periférico Carmino Real that seems to be partly illuminated by distinctive white-coloured streetlamps.
These night-time images of Earth from space clearly show the impact human settlement has on our planet. The light seen by astronauts is all wasted energy that could be better used for other purposes.