The search for life on Mars has entered a new era with the launch of a spacecraft built to sniff out waste gases released by alien organisms.

The ExoMars Trace Gas Orbiter (TGO) blasted into an overcast sky on a Proton rocket from Baikonur cosmodrome in Kazakhstan at 09:31 GMT on Monday.

A joint mission by the European and Russian space agencies, the probe will circle the red planet and measure minute levels of atmospheric gases, among which may be the natural waste products of microbial Martians.

Mission scientists hope in particular to get to the bottom of the Martian methane mystery. The gas is produced in abundance by life on Earth, and its presence on Mars could signify alien bugs on, or under, the surface. But the gas is also released by chemical reactions in rocks, so on Mars at least, scientists cannot yet be sure of its origins.

“Maybe, maybe we can find out if there’s life extant on the red planet,” said Mark McCaughrean, senior science adviser at the European Space Agency (ESA), moments before the launch.

Scientists have detected whiffs of methane on Mars before. In 2004, ESA’s Mars Express orbiter measured levels of methane in the atmosphere at about 10 parts in a billion, suggesting there is at least some being produced on the planet. Ten years later, NASA’s Curiosity rover recorded spikes in methane levels on the Martian surface, pointing to localized sources of the gas.

Read more at The Guardian.