Most Viral Photos: #3 Moon as Olympic ring

In the age of photo manipulation, this picture-perfect image looks artificial, but it's the real thing. A full moon added an out-of-this-world glowing sixth circle to the Olympic rings hanging from the top of London's Tower Bridge for the summer Olympics in London. Luke MacGregor, a sharp-eyed Reuters photographer, shot the photo, which was retweeted thousands of times within an hour of posting. (Photo by Luke MacGregor/Reuters)