Mars, the red Planet is known to have the presence of water millions of years ago. And now, scientists have decoded the phenomenon of how Mars lost its water that is equal to the global ocean.
The scientists found that water vapour near the surface of Mars is lofted higher into the atmosphere than expected. They found this using an instrument abroad NASA’s Mars Atmosphere and Volatile Evolution spacecraft. Once the water vapour reached the atmosphere, it is destroyed by electrically charged gas particles or ions. Once this happens, the vapour vanishes into the space.
The researchers who published the findings in Journal Science said that water continued to be lost from Mars even now. This is because vapour is transported to high altitudes after sublimating from the frozen polar caps during warmer seasons.
Shane W Stone, a doctoral student at the Lunar and Planetary Laboratory, Tucson, of the University of Arizona’s said that they were surprised to trace water so high in the atmosphere. Stone confirmed that that they were having only data from Mars Atmosphere and Volatile Evolution spacecraft. The scientists tracked abundance of water ions over Mars for more than two Martian years before they came to the conclusion.
They mainly focussed on the calculations when Mars was closest to the Sun. It was the time when it is warmer and dust storms are more likely to happen. The warm temperatures and strong winds along with dust storms help the water vapour to reach the uppermost parts of the atmosphere. This is easily broken into oxygen and hydrogen, which then escapes to the space. Stone also opined that everything that gets to the higher part of the atmosphere is destroyed, whether it is on Earth or Mars. This highest part is exposed to the full force of the Sun. They came across 20 times more water than usual over two days in June 2018. This was at the time of a global dust storm (the storm that NASA’s Opportunity rover out of commission).
The researchers concluded that Mars lost as much water in 45 days during this particular storm. Solar System Exploration Division, NASA, Director and NGIMS principal investigator reiterated that dust storms interrupt water cycle on Mars and push water molecules higher in the atmosphere. In the ensuing chemical reaction, hydrogen atoms are released and lost in space,” he said.
Though several scientists have found that Martian dust storms can lift water vapour far above the surface, no one has till now realised that water could make all the way to the top of the atmosphere.