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Where to look for life on the red planet

Mars

The potential biosphere of Mars can extend from the surface in some locations to a typical depth of 37 km, with many subsurface environments potentially hospitable for life.

By Eriita Jones & Charles Lineweaver

By determining the minimum criteria for life, researchers have narrowed down the locations where life may lurk on Mars.

Eriita Jones is a PhD candidate with Charles Lineweaver at the Australian National University’s Research School of Astronomy & Astrophysics. They originally published the research descreibed here in the journal Astrobiology (10, 349–61; 11, 1017–33).

The full text of this article can be purchased from Informit.

Is there life on Mars? It’s a difficult question to answer when we have only closely investigated the Martian surface in six locations where missions such as the Phoenix Lander and the Spirit and Opportunity rovers have sampled it directly.

Making the question even more challenging is that it is entirely plausible that the kinds of organisms that could have evolved to inhabit Mars’ unique environments have a different biochemistry to those on Earth, and would therefore be difficult to detect.

Despite these challenges, we have examined the chances for Earth-like life to thrive on present-day Mars. Studies of life on Earth have shown that there is strong potential for any world that harbours liquid-water to also harbour life, as all organisms require liquid-water during some phase of their life cycle. Hence searching for liquid-water is a logical approach to search for life on other planets, and “follow the water” is the mantra adopted by NASA and other space agencies.

Mars is a fascinating candidate for life as its surface is the most akin to Earth’s within our local neighbourhood, and it also records the occurrence of extensive liquid-water erosion throughout the past but also the present. Throughout the past ~4.5 billion years of Martian history, liquid-water has left its mark on the surface of the planet, scarring canyons, a temporary ocean,...

The full text of this article can be purchased from Informit.