Five instruments to explore Mars
13 August 2010
The scientific tools that will equip the Trace Gas Orbiter on the ExoMars mission in 2016 have been chosen. NASA and ESA completed the difficult task of deciding between the 19 candidate instruments in July.
Trace gases
A total of four American instruments and one Belgian instrument will be dispatched to probe the Red Planet.
Two of these will concentrate specifically on the chemical composition of its atmosphere: MATMOS and SOIR-NOMAD.
Their objective is to isolate “trace” gases, which are present in extremely small quantities but act as valuable indicators, reflecting activity on the planet’s surface and in its atmosphere.
Concentration of methane on the surface of Mars. Credits: NASA.
Eyes will be focused in particular on the mysterious methane detected in Mars’s atmosphere in 2003 by
“There is an apparent incompatibility between the methane measurements conducted by Mars Express and Earth-based observations, on the one hand, and the model developed by François Forget at the LMD* dynamic meteorology laboratory, on the other,” says Francis Rocard, head of solar system exploration programmes at CNES. “We have doubts about the reliability of the probe’s measurements. And ground observations are difficult to validate, since Mars methane is observed through Earth’s atmosphere, which also contains methane. Global models of atmospheric circulation have also revealed an inconsistency in the life cycle of methane on Mars.”
Biological or mineral?
Francis Rocard, head of Solar system exploration programmes at CNES. Credits: CNES/O. Pascaud.
Either way, this methane has sparked real curiosity among scientists. It could be produced by “Martian bacteria”, thereby proving that life currently exists on Mars.
But there is another theory. “Methane can also have a purely mineral origin,” explains Francis Rocard. “A particular type of serpentinization reaction produces methane when CO2 in the presence of water comes into contact with iron-rich rocks at high temperature.”
In this case, ecological niches could exist on Mars where the environment is conducive to developing and sustaining a form of biological activity.
Mars Express probe, in orbit around Mars since 2003. Credits: Ill. ESA.
In total, 10 French scientists at CNRS, the French national scientific research centre, will work on data from four instruments on the Mars Trace Gas Orbiter.
The first launch in 2016 will carry
In
The ExoMars missions could provide crucial information about life on Mars. They will also support preparations for a future sample return mission planned for the middle of the next decade.
* Laboratoire de Météorologie Dynamique, a joint CNRS/university research unit based at the École Polytechnique in Palaiseau, the École Normale Supérieure in Paris and the Université Pierre et Marie Curie, also in Paris
