That is a lot of water. Wonder how it got there.
There’s an old theory that Mars once had an atmosphere, but was of insufficient size for its gravity to hold it. Over millions of years it leaked out into space - only a trace is left. All liquid water was lost too, unless it was underground or permanently frozen. Some of my favorite science fiction is about ancient Mars civilizations, once vital but now dead or dying.
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The Martians, wanted to save their planet from global warming by reducing CO2. They succeeded wildly. CO2 levels dropped to the point where all plant life was extinguished which extinguished the production of oxygen. Without new CO2 production and no plants to make it, the remaining atmosphere slowly was scrubbed away by the solar winds.
he Martians, wanted to save their planet from global warming by reducing CO2. They succeeded wildly. CO2 levels dropped to the point where all plant life was extinguished which extinguished the production of oxygen. Without new CO2 production and no plants to make it, the remaining atmosphere slowly was scrubbed away by the solar winds.
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I get the joke, but actually there was a major disruption in the solar system resulting in one side of Mars being heavily bombarded and blowing off the atmosphere - prior to that event, the Martians fled to Earth. So returning is no big deal for Mars, just for the erstwhile explorers and colonists.