The first halogen gas on Mars has been detected, shedding new light on the history of the Red Planet.
The ESA-Roscosmos ExoMars Trace Gas Orbiter spacecraft detected hydrogen chloride, which is comprised of one hydrogen atom and one chlorine atom.
Gases based on chlorine or sulphur are possible indicators of volcanic activity, which Mars scientists were already looking to discover, but the new find has some strange qualities.
The fact that this particular discovery was made in distant locations at the same time, without any other gases that would be expected from Martian volcanos, means that an unknown process between the surface of the planet and its atmosphere is taking place.cientists suggest that salt – the remnants of Martian oceans – are lifted into the atmosphere by winds. Sunlight warms the atmosphere causing dust and water vapour to rise. These two components reach with each other to release chlorine, eventually producing hydrogen chlorine.
“The discovery of the first new trace gas in the atmosphere of Mars is a major milestone for the Trace Gas Orbiter mission,” says Håkan Svedhem, ESA’s ExoMars Trace Gas Orbiter project scientist, in a statement.“This is the first new class of gas discovered since the claimed observation of methane by ESA’s Mars Express in 2004, which motivated the search for other organic molecules and ultimately culminated in the development of the Trace Gas Orbiter mission, for which detecting new gases is a primary goal.”