It can be interesting to look for rectangular spots of discoloration on the zoomed-out views, because these are areas of high-res imagery. Sometimes you notice a high-res area that is not in a place you would expect. Why is this spot so interesting to people with imaging satellites? The answer to this spot is: it is the location of Communist North Korea's nuclear weapons facility. The actual fuel-producing reactor is above the loop, just inside the curve.
Power - Nuclear, Government - National - Foreign