Scientists on an ice floe

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Climbers crossing a crevasse

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Explorers at base camp

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Climber on a mountain face

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Mount Everest peak

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Climber on ladder over glacier

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Climbers on K2 mountain

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Caver exploring a cave

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Grassy field with a dead tree

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Forest trail among redwood trees

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Mars map from National Geographic

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abandoned research lab

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Climbing an ice wall

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Antarctic research station

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Polar bear near research station

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Tornado research vehicle in field

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Tree roots in a forest

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ancient oak tree in forest

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Climber Silhouette in Canyon

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Ancient gnarled tree in forest

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