Night lights can reveal a lot about the distribution of people
on the landscape, or “human geography.” In this astronaut photograph from the
International Space Station (ISS), the lights of Qatar show informative
demographic detail that is very difficult to discern in daylight
images—especially in deserts, where even large cities can be hard to see.
The brightest group of lights at image center is the capital
city, Doha, with the neighboring smaller ports of Ad-Dahira and Umm Sa’id to
the north and south. (Note that north is to the left, due to the path of the
ISS orbit.) Highways are clearly visible leading west from the capital to the
Dukhan oil fields, to Saudi Arabia, and to the north of the country
where—judging by the lack of night lights—the population is probably very low.
The relatively minor coast road between the oil fields and the Saudi frontier
also stands out.
Almost the entire island nation of Bahrain appears at lower
left, with the capital city of Manama nearly as bright as the lights of Doha.
The difference in light intensity reflects a difference in population; Doha has
1.45 million inhabitants, while the dense Manama metro area has a population of
1.2 million.
While some night views are informative about a landscape, they
can also be difficult and confusing to locate. Astronauts learn to recognize
where they are at night by flying over populated places repeatedly.
Coastlines—one of their best geographic indicators—are generally lost to view
because water surfaces and unpopulated land surfaces look the same without
illumination such the full moon.
Thus, the thumb-shaped Qatari peninsula, so well-known in Middle
Eastern geography, does not show up at all in this nighttime photograph.
However, the low-light imaging bands of the Visible Infrared Imaging Radiometer
Suite on the Suomi NPP satellite showed the Qatari peninsula and the long arm
of the Gulf of Bahrain (lower image) on a moonlit night. The image was acquired
during the early morning hours of September 30, 2012, two weeks before the
astronaut photograph.
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