Mars could be losing water from its atmosphere at a faster rate than anyone predicted

Mars appears to be losing was from its surface at a much faster rate than scientists anticipated from past observations. The slowly-disappearing water makes up part of the upper atmosphere of Mars, where sunlight causes water molecules to split apart, forming atomic hydrogen and oxygen (H2 and O2) that the weak gravity of Mars cannot prevent from escaping into space. An international team of researchers, led partly by French National Centre for Scientific Research (CNRS) researcher Franck Montmessin, showed that water vapour is accumulating in large quantities and unexpected proportions some at an altitude of roughly 80 kilometres in the Martian atmosphere. [caption id=“attachment_6374211” align=“alignnone” width=“1280”] The near-invisible, delicate-looking atmosphere of Mars.[/caption] The researchers identified and measured large pockets in the atmosphere that are in a “supersaturated” state — the atmosphere holding between 10 and 100 times the water vapour that its temperature can theoretically allow. While an interesting problem for researchers to address, the supersaturated state also means that the capacity for Mars to lose water from these spots is much higher in some seasons. The water will be lost to space, and useless to The data supporting the study was obtained by the Trace Gas Orbiter, a probe on the ESA-Roscosmos ExoMars mission. These findings from the study were **published in _Science_**  on 9 January 2020.