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Why do we want to go to Mars so badly? The first answer that comes to mind is: to look for alien life.
You might think that, being an astrobiologist, I am biased. And you are probably right: microbes matter to me more than rocks, and if you’re a geologist you’re probably yelling at your screen. But the search for life is usually at the top of mission objectives when it comes to Mars. Mars has not always been the dry, cold and desert planet it is today. Evidence suggests that, at some points in its history, it was surrounded by a denser atmosphere, had lakes, rivers and oceans, and was warmer. The large amounts of nutrient-rich volcanic rocks, together with atmospheric gas, likely provided all the elements needed to support microbial life forms as we know them.
Artistic representation of a primitive ocean on Mars. Credits: NASA/GSFC.
That being said, the fact that a planet has everything it needs to sustain life does not mean that it sustains life. “Where there is water, there is life”, as you might have read quite a few times, is a ...