ExoMars Rover To Test For Microbial Life On The Red Planet
John P. Millis, PhD for redOrbit.com – Your Universe Online
In 2018, the European Space Agency (ESA) will launch a new mission to Mars called ExoMars. Armed with new instruments, this explorer will beam back information about various conditions and properties on the Red Planet’s surface. One such instrument will be the Raman spectrometer – a device similar to a bomb detector that will search for evidence for life.
The Raman spectrometer has the ability to detect life that has been damaged by significant levels of radiation – an environment certainly reminiscent of Mars, which lacks a protective atmosphere and magnetic field. According to Lewis Dartnell of the University of Leicester: “Raman spectroscopy is a wonderfully sensitive and versatile technique. It can reveal details of the minerals inside rocks, and so what the micro-environment for life is, but we can also use it to detect organic molecules and signs of life itself.”
In testing the spectrometer, Dartnell and his team exposed bacteria to high doses of radiation, thousands of times the level that would kill a human, and found that carotenoid molecules – a key marker of life – could still be identified.
“What we’ve been able to show is how the tell-tale signature of life is erased as the energetic radiation smashes up the cells’ molecules,” said Dartnell. “In this study we’ve used a bacterium with unrivalled resistance to radiation as a model for the type of bacteria we might find signs of on Mars.”
“What we want to explore now is how other signs of life might be distorted or degraded by irradiation. This is crucial work for understanding what signs to look for to detect remnants of ancient life on Mars that has been exposed to the bombardment of cosmic radiation for very long periods of time.”
But the most important question of all remains: Did life ever evolved on the Martian surface to start with? The ExoMars mission, armed with the Raman spectrometer may begin to provide some answers when it launches in 2018.