Ever wonder why there are so many more stars up in the mountain or across the desert? Well, it's because of light pollution, or excessive, misdirected, or obtrusive artificial light. Light pollution is a side effect of industrial civilization. Its sources include building exterior and interior lighting, advertising, commercial properties, offices, factories, streetlights, and illuminated sporting venues. It is most severe in highly industrialized, densely populated areas of North America, Europe, and Japan and in major cities in the Middle East and North Africa like Tehran and Cairo, but even relatively small amounts of light can be noticed and create problems. Here's what some big cities would look like without any light pollution. Click here to view the first image in this week's WINS gallery. Continue reading for a viral video of a natural gas explosion on a busy freeway in Russia.