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Photo Credit: NASA/JPL/Malin Space Science Systems
https://mars.nasa.gov/gallery/global/PIA02653.html
The Mars that was and the Mars that is are two very different things. Three or so billion years ago, the Red Planet was awash with water, as now-dry riverbeds, deltas, and ocean basins reveal. But when the planet lost its magnetic field, it lost its protection from the solar wind, which stripped away much of the planet’s atmosphere and allowed most of its water to escape to space.
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