Many scientists predict -- shockingly -- that the entire North Polar ice cap may be completely gone during summer months during the first term of the next president.

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The five-week cruise set off on July 4 and is now in the sub-polar region of the North Atlantic between Greenland and Iceland.

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It is in a so-called polar orbit: each turn around Mars takes it over the north and south poles while the planet revolves beneath it.

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