Río Tinto is a peculiar place in our planet that has many similarities with Mars. The most important one is iron. Mars is red because of its iron, and Río Tinto is the red river.
The river’s singular red colour comes from ferric ion, iron oxidised due to the river’s acidity...
Considering the similar geochemistry and minerology, this place is a good analogue to Mars. Life on Mars would probably look like life here.
During his trips to South America, Charles Darwin found life in extreme saline conditions. He then predicted that we would find life in the subsoil. It took us 200 years to prove him right. If there is life on Mars, as some of us believe, it has to be in the subsoil.
What definitely equialised Río Tinto and Mars was the discovery of jarosite in Mars. This iron and potassium sulphate is produced in great quantities in Río Tinto.
Upon drilling the river’s subsoil, scientists found a great variety of bacteria and microorganisms. These could thrive in extreme conditions, and need no oxygen.
Question: Is it possible to better explain the connection (if any) between jarosite and subsoil biological activity that's hinted at by the video?
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