New study by the University of Leicester and The Open University into evidence of water on Mars, found that hydrothermal fractures around Martian impact craters may have been a habitable environment for microbial life.
The study determined that water temperatures on the Red Planet ranged from 50 to 150 degrees Celsius. Microbes on Earth can live in similar waters, for example in the volcanic thermal springs at Yellowstone Park, the scientists note.
The research is based on detailed scrutiny of Mars meteorites on Earth using powerful microscopes in the University of Leicester Department of Physics and Astronomy. This was followed-up by computer modeling work at The Open University.
"Rovers on Mars - the Mars Exploration rovers Spirit and Opportunity, and the Mars Science Laboratory rover Curiosity - are studying rocks to find out about the geologic history of the Red Planet. Some of the most interesting questions are what we can find out about water, how much there was and what temperature it might have had," researcher John Bridges, from the University of Leicester Space Research Centre said.
"While the orbiters and rovers are studying the minerals on Mars, we also have meteorites from Mars here on Earth. They come in three different groups, the shergottites, the nakhlites and the chassignites.
"Of most interest for the question of water on Mars are the nakhlites, because this group of Martian meteorites contains small veins, which are filled with minerals formed by the action of water near the surface of Mars," said Bridges.
Bridges and his group studied those alteration minerals in great detail. Altogether eight nakhlite Martian meteorites are known, and all have small but significant differences between them and in their alteration minerals.
Lafayette is one of them; and the most complete succession of newly formed minerals can be found in its veins. Careful investigations of the minerals with an electron microscope and a transmission electron microscope have revealed that the first newly formed mineral to grow along the walls of the vein was iron carbonate.
The carbonate would have been formed by CO2-rich water around 150 degree Celius. When the water cooled to 50 degree Celsius, it would have formed the clay minerals, which were then followed by an amorphous phase that has the same composition as the clay.
Microbes use the reactions during mineral formation to gain energy and elements essential for their survival. Sufficiently warm enough to support life, has been published this week in the journal Earth and Planetary Science Letters.