On Tuesday 06 Sep 2011 2:53:21 pm Eugen Leitl wrote:
> http://i.imgur.com/9FxTe.jpg
>
> Security illumination.
>
Here is the explanatory note along with the image
>ISS028-E-029679 (21 Aug. 2011) --- A night time view of India-Pakistan
> borderlands is featured in this image photographed by an Expedition 28 crew
> member on the International Space Station. Clusters of yellow lights on the
> Indo-Gangetic Plain of northern India and northern Pakistan reveal numerous
> cities both large and small in this photograph. Of the hundreds of
> clusters, the largest are the metropolitan areas associated with the
> capital cities of Islamabad, Pakistan in the foreground and New Delhi,
> India at the top - for scale these metropolitan areas are approximately 700
> kilometers apart. The lines of major highways connecting the larger cities
> also stand out. More subtle but still visible at night are the general
> outlines of the towering and partly cloud-covered Himalayan ranges
> immediately to the north (left). A striking feature of this photograph is
> the line of lights, with a distinctly more orange hue, snaking across the
> central part of the image. It appears to be more continuous and brighter
> than most highways in the view. This is the fenced and floodlit border zone
> between the countries of India and Pakistan. The fence is designed to
> discourage smuggling and arms trafficking between the two countries. A
> similar fenced zone separates India's eastern border from Bangladesh (not
> visible). This image was taken with a 16-mm lens, which provides the wide
> field of view, as the space station was tracking towards the southeast
> across the subcontinent of India. The station crew took the image as part
> of a continuous series of frames, each frame taken with a one-second
> exposure time to maximize light collection -- unfortunately, this also
> causes blurring of some ground features. The distinct, bright zone above
> the horizon (visible at top) is produced by airglow, a phenomena caused by
> excitation of atoms and molecules high in the atmosphere (above 80
> kilometers, or 50 miles altitude) by ultraviolet radiation from the sun.
> Part of the ISS Permanent Multipurpose Module, or PMM, and a solar panel
> array are visible at right.
