New Delhi, June 1 -- Images generated by US National Aeronautical Space Agency (Nasa) satellites have been able to conclusively measure changes in the intensity of artificial light at night (Alan)-which bears a direct correlation with human activity and is one of the fundamental indicators of modern societal development.

Globally, one of the biggest changes could be seen in India-a direct result of increased urbanization in the southern and western regions of India and increased access to electricity in northern India.

This is not surprising; over the last decade, India has provided electricity access to 30 million households that were previously deprived of access; close to 15 million of these households belong to the northern states o...