Chatham Islands, New Zealand

An expansive bloom of phytoplankton (single-celled, plant-like organisms) traced colorful swirls across the South Pacific Ocean between New Zealand (left) and the Chatham Islands (right) on December 23, 2009. The colors come from chlorophyll and other pigments that the phytoplankton use to capture light for photosynthesis. The milky turquoise parts of the bloom may include phytoplankton called coccolithophores, which have a chalk-like plating that is very reflective.