Iridescence

At the Curitiba Botanical Garden, photographer Mendonca Jr glanced up from the statuary and beheld a colorful iridescent cloud: "The silhouette below the cloud is not a real person, but a statue called the Mother," he explains. She is located at the center of a fountain--hence the splashing water. There is water in the cloud, too. Tiny water droplets diffract sunlight, giving rise to the cloud's soft pink and green colors. The key word is tiny. For diffraction to work properly, the cloud's droplets must be about 1000 times smaller than the ponderous drops we see splashing around the statue. Tiny droplets, big droplets. Altogether, "it was a lovely scene," he says.

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