Grotzinger said the discovery signifies the real beginning of the rover's science mission.
Now that scientists have proof that water once flowed across Mars, they can begin to look for signs of other elements, such as carbon, that are also needed to support life.
"Now we look at more rocks," said Grotzinger. "We get more context. We need to recreate the environment with even greater detail, with an understanding of the chemistry going on at that time, to understand if this was an area where an organism once lived. Was this an inhabitable environment? That is still to be determined."
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