Astrobiology Top 10: Welcome to Mars, TGO!

As 2016 comes to a close, Astrobiology Magazine is counting down our ‘Top 10’ stories from the past year. At number 9: The European Space Agency and Roscosmos, the Russian Space Agency, celebrated as their joint satellite ExoMars with its Trace Gas Explorer (TGO) slid into orbit around the red planet. This story was originally published on October 20, 2016.


Artist's impression visualising the ExoMars 2016 Trace Gas Orbiter (TGO), with its thrusters firing, beginning its entry into Mars orbit on 19 October 2016. Photo Courtesy of the ESA/ATG medialab.

Artist’s impression visualising the ExoMars 2016 Trace Gas Orbiter (TGO), with its thrusters firing, beginning its entry into Mars orbit on 19 October 2016. Photo Courtesy of the ESA/ATG medialab.

On October 19, the European Space Agency (ESA) and Roscosmos, the Russian Space Agency, celebrated as their joint satellite ExoMars with its Trace Gas Explorer (TGO) slid into orbit around the red planet. This is only the second time that ESA has successfully put a satellite into orbit around Mars. The last time was 2003, when Mars Express arrived to study the atmosphere and look for water. For the last 13 years, Mars Express has sent back brilliant pictures of how water has changed the surface of our neighboring world and captured the scintillating ultraviolet auroras that shine over the north and south poles. TGO’s mission builds on that search for life by detecting another compound linked with life: methane.

As we described in our article last year, most of the methane on Earth comes from active life (usually microbes). The rest is formed when hot water interacts with rock. Either way, we are very interested in homing in on where the methane on Mars is coming from and when. Is it seasonal? Does it happen only in certain locations? Is the methane production stable year after year or does it alter with time? With its four instruments capable of sniffing out hydrocarbons like methane in less than 1% of the atmosphere, the Trace Gas Orbiter will start to answer those questions once ExoMars has maneuvered into position to peer through the Martian atmosphere for signs of breathing microbes, active geology, or, possibly, both.

Artist's impression of the ExoMars 2016 Trace Gas Orbiter (TGO) and Schiaparelli – the entry, descent and landing demonstrator module. Copyright: ESA/ATG medialab

Artist’s impression of the ExoMars 2016 Trace Gas Orbiter (TGO) and Schiaparelli – the entry, descent and landing demonstrator module. Copyright: ESA/ATG medialab