It's been a long time coming, but Europe and Russia are finally going back to Mars. On March 14, the ExoMars Trace Gas Orbiter (TGO) will launch from the Baikonur Cosmodrome located in Kazakhstan aboard a Proton rocket. The launch will mark the first step in a mission that aims to understand the Red Planet's atmosphere, as well as look for clues of biological and geological activity.
The spacecraft is set to arrive on Mars on Oct. 19 and will carry a small lander named Schiaparelli. Schiaparelli will land on the surface and give the European Space Agency (ESA) and Roscosmos teams landing practice time in preparation for the launch of the ExoMars rover sometime in 2018.
One of the keys to determining if Mars is as dead as it seems is establishing a connection between gases in the air and their origins on the surface. Since gas breaks down in sunlight after just a few hundred years, any found on Mars will have been created recently.
The TGO is equipped with two suites of spectrometers that are designed to pinpoint the planet's atmospheric gases down to the most minute amounts, as well as a camera for capturing potential ground sources and a neutron detector to detect ice up to a meter below the planet's surface.
"These missions are specifically designed to see if life has ever existed on Mars and if it still survives," said Andrew Coates, deputy director of University College London's Mullard Space Science Laboratory. "Methane is one of the key gases we are looking for."
"We know from other missions that it is coming from under the surface, and there are only two possible sources: geothermal activity or, mind-blowingly, some form of life, almost certainly microbial," he added.
Trace amounts of atmospheric gases will help the team crack Mars's methane mystery. If they find that the methane contains sulphur dioxide and can be connected to geographic surface features, it is likely that volcanic activity existed on Mars. However, methane with higher levels of the isotope carbon-12 would point to the potential for biological life.
"The emerging picture is that soon after Mars formed, around 4.6 billion years ago, it was a very suitable place for life," Coates said. "The question is whether life, or its remains, might persist underground."
Although hopes are high for the mission, both the ESA and Roscosmos do not have a great track record when it comes to Mars. The ESA's only Mars mission failed to retrieve its British-built lander, Beagle 2, and the Soviet Union has conducted more than a dozen Mars missions, none of them ending in complete success.
