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Scientists have always presumed that

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Mars had a much warmer and

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more watery past, but

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estimates of how much water Mars has lost

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since its formation 4.5 billion years ago

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are extremely low. Now

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researchers at the NASA Goddard

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Space Flight Center have obtained  the

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most accurate measurement when measuring the

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proportion of heavy water on Tuesday

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especially in regions near the

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polar caps the new measurements

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suggest that at least 20% of the

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planet was covered by water with

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some regions with depths of

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more than a kilometer over time  Nearly

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90% of this ocean was lost to

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space with the remainder currently

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stored

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mainly in the polar caps on

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Tuesday. This new image of Mars is

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considerably wetter than

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estimated from isotopic measurements and would

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suggest that water may have

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persisted longer.  throughout