Mars Atmosphere Contains More Water Than Previously Suspected

According to a new study the atmosphere on Mars contains up to a hundred times more water than previously suspected. Using data from the European Space Agency’s Mars Express probe and NASA’s Mars Reconnaissance Orbiter, astronomers determined that water in the Martian atmosphere undergoes a process known as supersaturation, something astronomers thought could not occur on the dry, dusty planet. Under most climate conditions, water vapor coalesces around dust and particles in the air. When such dust is sparse, climate models have long assumed that the excess water in the atmosphere on Mars is then converted to ice. But data from Mars Express’ SPICAM instrument shows otherwise.

According to Franck Montmessin, of the Laboratoire Atmospheres, Milieux, Observations Spatiales (LATMOS) in France their observations show that as much as ten to a hundred times more water vapor can subsist in a state of supersaturation. In supersaturation, more of the water vapor gathers around the dust particles than would be possible under normal circumstances. Existence of supersaturation has profound consequences for the migration and further persistence of water everywhere on the planet. Since the conditions on Mars were thought to impede supersaturation rather than encourage it, the present climate models don’t include the process and will need to be revised.