Double-Double Rainbow!

Today I learned that quadruple rainbows exist! Even though I don't quite understand... I think the extra ones are behind you when you see the double rainbow?

http://news.nationalgeographic.com/news/2011/10/pictures/111007-first-quadruple-rainbow-triple-science-optics/#/triple-quadruple-rainbows-spotted-four-field_41572_600x450.jpg