光源广告
光源广告-
人造卫星在每天凌晨1点30分拍摄一张该城市的图像，结果发现，80%的城市光因被射向天空而被浪费掉，这些光亮来自非路灯光源，包括大型广告牌、招牌、泛光灯和建筑物立面。
Capturing an image of the city at 01:30 every morning revealed that 80 % of the urban light that was wasted by being beamed upward into space was from non-streetlight sources , including billboards2 , signs , floodlights , and facades3 .