New light on the possibility of life on Mars

Curiosity discovered lumps of clay in an area on Mars known as "Yellowknife Bay" (Yellowknife Bay) inside Gale Crater that could only have formed in a wetter period

Humanity is curious by nature, in particular about the aspects of life on other planets and as a result the question of whether we are alone or not? The vehicle known as "Curiosity", surveys the surface of Mars in search of a place where life can exist, or at least could have existed in the past. Two researchers from Stony Brook University, Prof. Scott McLennan and Joel Horowitz, published their interesting findings in no less than 6 different studies published in the online version of the journal Science on December 9.

"We determined that the rocks retained their properties in the ancient geological environment, which made life possible at the bacterial level," said McLennan, who was chosen as a partner scientist in the Red Scientific Laboratory project whose representative on Mars soil is the robot Curiosity. While Horowitz adds: "Curiosity carried out its work in an area on Mars known as "Yellowknife Bay" inside Gale Crater. Curiosity was able to fully characterize its environment in terms of the interplay between geology and geochemistry.

This insight is essential to understanding the circumstances under which Mars could theoretically support life. The main models of the history of Mars show that the planet had enough fresh water to produce clay-derived minerals - and possibly even could have supported life - over 4 billion years ago, but it experienced a drought that changed conditions to more acidic and salty. A key question about the clay minerals in the Yellow Knife Bay is whether they were formed at an early stage of the Medic history - inside the crater itself or later and these materials were carried away by the water that flowed and sank?

Prof. McLennan and his staff determined that the chemical elements in the rocks indicate that the particles were transported by rivers to the Yellow Knife Bay without experiencing chemical changes until a certain period after they sank. If the events that turned some of the volcanic minerals into clay in the original area where these particles were formed, one would expect to find a minority of water-soluble substances - in particular calcium and sodium. The evidence shows that this did not happen and that much geochemical activity occurred late in the history of the rocks found at the site.

The place where the clay was formed was probably an ancient lake bed, which contained water that was neither too acidic nor too salty and had the right composition of elements that could become a source of energy for life. The energy source was perhaps similar to those used by primitive rock-eating bacteria on Earth - a mixture of sulfur and iron that allows the transfer of electrons, similar to simple batteries.

"The findings illustrate the fact that the geochemical environment of early Mars was good for life," McLennan said. "It warrants further research to determine whether life really exists on Mars. The age of the rocks is slightly younger than previously thought could support such environments. This means that the current understanding of the evolution of surface conditions on Mars requires a new interpretation.”

Curiosity landed in Gale Crater on Mars on August 5, 2012 for a two-year primary mission. The four main tasks that will be examined are: the biological potential, the geological characterization of the landing area, the study of the planetary processes relevant to life in the past, including the role of water, and the description of radiation on the surface.

The record of the climate and geology of Mars is preserved in the rocks and soil formations, the structure, and the chemical composition. The samples pulled from the ground by excavators were analyzed for the geology and radiation around the event of their formation. The devices inside the vehicle examine these samples in an attempt to locate the chemical building blocks of life - in particular different configurations of carbon, and to assess whether the Martian environment allowed life in the past.

Horowitz is happy about the impressive state of preservation of these rocks despite their ancient age. "Finding ancient sedimentary rocks is a very difficult thing on Earth," he said. "However, such rocks appear to be common on Mars, making it an excellent target for understanding the early history of water-covered planets in our solar system and beyond."

Curiosity has already moved more than 8 kilometers from Yellowknife Bay and is moving towards the base of Mount Sharp in the center of Gale Crater, which was the primary objective of the mission. "He is expected to arrive there at some point in 2014, when he will begin the initial part of the mission for which he was sent. The height of this mountain is about 5 kilometers and it consists of many layers of rocks," Horowitz added.

For the announcement of the researchers on the Stony Brook University website