Rio Tinta: "Martian" river on Earth

The unusual surroundings of mining mines near the Rio Tinta River in the province of Huelva (Spain) are strikingly reminiscent of the Martian landscape. For many years it was believed that the characteristic "Martian" color of the soil and water was caused by pollution from the mines.

At the end of the 19th century, the British founded the Río Tinto Mine Company here, which operated for several decades. After the extraction of copper ore turned out to be unprofitable, the mines were closed.

Now scientists are sure that the color of the local soil is mainly due to natural causes.

The Rio Tinto basin is rich in metal ores. And although almost the entire periodic table is represented here, iron prevails, the oxides of which give a peculiar reddish tint to the soil and water.

Strange microorganisms called chemolithotrophs live here, feeding on inorganic compounds. They also oxidize iron sulfite, which is found in excess in local soil, turning it into sulfuric acid and ferric chloride.

Three years ago, in the Rio Tinto basin, they even tested equipment that can be used to study Mars in conditions, so to speak, as close to real as possible - the Eurobot rover and testing new space suits.

“The Rio Tinto pool is almost ideal for such challenges. In addition, this area is very close to inhabited areas, which makes it easier to organize expeditions,” Felipe Gomez, a researcher at the Center for Astrobiology and coordinator of the Europlanet project, told El Mundo.