The Antarctic Ross Sea, south of New Zealand, comes to life each southern-hemisphere summer, as the surface ice thaws and pockets of water known as polynyas appear. In the above true-color image from NASA's Aqua satellite, the bright green colors of microscopic plants -- phytoplankton -- spreads across the dark blue water. The phytoplankton will be eaten by krill, fish, penguins, and whales.

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Image: NASA.