August 12, 2008—Phytoplankton are tiny marine organisms, but when they congregate en masse the resulting swirl can be seen from space.

The Terra satellite imaged this phytoplankton bloom on August 7 off the east coast of Hokkaido, Japan.

These one-celled plants use sunlight to convert carbon dioxide and nutrients into new organic compounds at the base of the ocean's food chain.

The watery bloom gets its green hue from chlorophyll and other pigments used for photosynthesis.

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