* Astronomy

Title: New approaches to the exploration: planet Mars and bacterial life
Authors: Giuseppe Galletta (UniPD), Giulio Bertoloni (UniPd), Maurizio D'Alessandro (INAF-OAPD)

Planet Mars past environmental conditions were similar to the early Earth, but nowadays they are similar to those of a very cold desert, irradiated by intense solar UV light. However, some terrestrial lifeform showed the capability to adapt to very harsh environments, similar to the extreme condition of the Red Planet. In addition, recent discoveries of water in the Martian permafrost and of methane in the Martian atmosphere, have generated optimism regarding a potentially active subsurface Mars' biosphere. These findings increase the possibility of finding traces of life on a planet like Mars. However, before landing on Mars with dedicated biological experiments, it is necessary to understand the possibilities of finding life in the present Martian conditions. Finding a lifeform able to survive in Martian environment conditions may have a double meaning: increasing the hope of discovering extraterrestrial life and defining the limits for a terrestrial contamination of planet Mars. In this paper we present the Martian environment simulators LISA and mini-LISA, operating at the Astronomical Observatory of Padua, Italy. They have been designed to simulate the conditions on the surface of planet Mars (atmospheric pressure,0.6-0.9 kPa; temperature from -120 to 20 °C, Martian-like atmospheric composition and UV radiation). In particular, we describe the mini-LISA simulator, that allows to perform experiments with no time limits, by weekly refueling the liquid nitrogen reservoir. Various kind of experiments may be performed in the simulators, from inorganic chemistry to biological activity. They are offered as experimental facilities to groups interested in studying the processes that happen on the Martian surface or under its dust cover.

Read more (1253kb, PDF)

Ancient Mars More Favourable to Life than First Thought

A couple of Mars orbiters have found evidence suggesting that water prevailed throughout the Red Planet's early history. That's significant because scientists until now believed that wet conditions only prevailed in the southern reaches of Mars.
The discovery of lay minerals point to the existence of a wet environment "at thousands of sites" in the southern region of Mars, an area where rocks date back approximately four billion years old, according to a report from NASA's Jet Propulsion Lab.
Read more

Common Mars rock can preserve microfossils after all

Life on Mars, if it ever existed, may be easier to find than previously thought. New research on terrestrial rocks suggests that a type of rock common on Mars can preserve fossilised microbial life, rather than erasing evidence of it as previously thought.
Minerals called sulphates, which form in the presence of liquid water, have been found in great abundance on Mars, including at the landing site of NASA's Opportunity rover, Meridiani Planum.
Read more

Look for Mars life with laughing gas

Trace amounts of laughing gas, or nitrous oxide, in Mars's atmosphere could aid the search for life on the Red Planet.
Vladimir Samarkin, of the University of Georgia in Athens, and colleagues found that the nitrite-rich water of hypersaline Don Juan pond in Antarctica reacts with minerals in volcanic rock to produce nitrous oxide.
Since the geology, sub-zero temperatures and brine geochemistry of the lake closely resemble those of Mars, the researchers say the process could be an important component of the Martian nitrogen cycle.
Read more