The ExoMars Trace Gas Orbiter is a collaborative project between the European Space Agency (ESA) and the Russian Roscosmos agency that sent an atmospheric research orbiter and the Schiaparelli demonstration lander to Mars in 2016 as part of the European-led ExoMars programme. A key goal is to gain a better understanding of methane and other trace gases present in the Martian atmosphere that could be evidence for possible biological activity.