Astronauts on board the International Space Station took this picture of Ile aux Cochons, an island in the southern Indian Ocean that is home to the world's largest colony of King Penguins. The wave clouds form as air rises over the island's summit, falls in its wake, and then continues in a cycle of uplift and descent between bands of moist and dry air, resulting in clouds in the former. Ile aux Cochons is a stratovolcano that rises some 2,500 feet above sea level. It is uninhabited by humans.
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