(SkyNews) An announcement by NASA in 2015 that liquid water had been found on Mars was premature, according to new research.
At a news conference that year, NASA's director of planetary science declared: "Liquid water has been found on Mars."
Scientists reasoned that water must be present on the red planet to explain mysterious darkish streaks that appeared to ebb and flow with the seasons.
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However, while there is water on Mars - existing on the polar caps, ground ice, as well as in frosts and hydrated minerals - the evidence suggesting larger volumes of liquid water is ambiguous, according to researchers from the US Geological Survey.