Washington, Nov. 15
Scientists have further destroyed the phenomenon that caused Mars to lose the equivalent of a global ocean of water up to hundreds of feet deep over billions of years.
Scientists using an instrument aboard NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft have discovered that a lump of water near the surface of the Red Planet is higher in the atmosphere than one might expect. any.
There, it is easily destroyed by particles of electric gas – or ions – and lost to space.
Mars is still losing water today as vapor is transported to high altitudes after sublimating from the frozen polar caps at warmer seasons, the team wrote in the journal Science.
“We were all surprised to find such high water in the atmosphere,” said Shane W Stone, a doctoral student in planetary science at the Lunar and Planetary Laboratory at the University of Arizona in Tucson.
“The measurements we used may only have come from MAVEN as it passed up through the atmosphere of Mars, high above the surface of the planet. ”Until they discovered, Stone and his team discovered the abundance of water ions high above Mars for over two Martian years.
In doing so, they concluded that the level of water valve near the top of the atmosphere is about 150 km, above the highest surface in summer in the southern hemisphere.
During this time, the planet is closest to the Sun, and therefore warmer, and dust storms are more likely to occur.
Warm summer temperatures and strong winds associated with dust storms help water valves reach the highest parts of the atmosphere, where they can easily break down into oxygen and hydrogen.
The hydrogen and oxygen then escape into space. Previously, scientists believed that a lump of water was trapped near the Martian surface as it is on Earth.
“Everything that makes it up to the higher part of the atmosphere is destroyed, on Mars or on Earth,” Stone said, “because this is the part of the atmosphere that is exposed to the full power of the sun. . ” The researchers measured 20 times more rain than usual over two days in June 2018, when a storm sent global dust around Mars (the one that NASA’s Access rover commissioned).
Stone and his colleagues believed that Mars lost as much water in 45 days during this storm as usual throughout the entire Martian year, which lasts two years on Earth.
“We have shown that dust storms disrupt the water cycle on Mars and push water molecules higher into the atmosphere, where a chemical reaction can release their hydrogen atoms, which in turn lost to space, ”said Paul Mahaffy, director of NASA Goddard ‘s Solar System Research Division and NGIMS chief investigator.
Other scientists have also discovered that Martian dust storms can raise water vapor far above the surface.
But no one had realized until now that the rain would make it all the way to the top of the atmosphere.
“What is unique about this discovery is that it gives us a new way that we never thought existed for water to escape the Martian environment,” said Mehdi Benna, a Goddard planetary scientist and co-researcher of the NGIMS MAVEN instrument.
“It will fundamentally change our estimates of how fast water is escaping today and how fast it has escaped in the past. ”- IANS