I found this via facebook but if this is an accurate picture; the population centres are immediately visible. What strikes our is the relatively prosperity of the Punjab, urban South India (the belt which starts from Gujarat/Maharashtra) and of course the Colombo area. West Bengal and Calcutta seem to stand out as a “beacon of light” in the trail from Delhi to Chittagong. The poverty & population of South Asia is concentrated in this belt; “Aryavarta” and should HDI/economic growth pick up here (I understand Bihar has a high economic growth rate) then South Asia as a whole will lift up. Visually in some aspects India seems to resemble America with its coastal/hinterland dichotomy.
I found an interesting map on the NASA website, where there seems to be a very high correlation between global economic influence/weight and relative illumination on the map (also this is a Mercator map which exagerates areas far from the equator). Oh and happy Diwali.