The giant Martian sandstorm of 2018 wasn’t just a wild ride – it also gave us a previously undetected gas in the planet’s atmosphere. For the first time, the ExoMars orbiter sampled traces of hydrogen chloride, composed of a hydrogen and a chlorine atom.
This gas presents Mars scientists with a new mystery to solve: how it got there.
“We’ve discovered hydrogen chloride for the first time on Mars,” said physicist Kevin Olsen of the University of Oxford in the UK.
“This is the first detection of a halogen gas in the atmosphere of Mars, and represents a new chemical cycle to understand.”
Scientists have been keeping an eye out for gases that contain chlorine in the atmosphere of Mars, since they could confirm that the planet is volcanically active. However, if hydrogen chloride was produced by volcanic activity, it should only spike very regionally, and be accompanied by other volcanic gases.
The hydrogen chloride detected by ExoMars did not, and was not. It was sniffed out in both the northern and southern hemispheres of Mars during the dust storm, and the absence of other volcanic gases was glaring.
This suggests that the gas was being produced by some other process; luckily, we have similar processes here on Earth that can help us understand what it could be. Read from source….