A new study suggests that the overwhelmingly large amount of perchlorates found in the soils of Mars may be created by the intense electricity of Martian dust storms. However, it is not the lightning itself that does this, but rather a different kind of electrostatic discharge.
As Phys.org report, Alian Wang, research professor in the Department of Earth and Planetary Sciences at Washington University in St. Louis, explained that the mechanism they had discovered on Mars was completely new and is able to come into being from both dust storms and dust devils, events that happen frequently and over large expanses of the planet. As part of the new research, scientists have recreated conditions on Mars inside of a laboratory on Earth.
“We found a new mechanism that can be stimulated by a type of atmospheric event that’s unique to Mars and that occurs frequently, lasts a very long time and covers large areas of the planet—that is, dust storms and dust devils. It explains the unique, high concentration of an important chemical in Martian soils and that is highly significant in the search for life on Mars.”
After NASA’s Phoenix Mars Lander first hit Mars in its quest to hunt down areas that might be be suitable for microbial life, scientists discovered that there were enormous levels of perchlorates in the soils of Mars which were found to measure at between 0.5 to 1.0 percent.
While it may have once been assumed that these perchlorates would ensure that no microbial life could survive on Mars, it turned out that some microbes are actually capable of using these same perchlorates as a powerful source of energy that fuels them.
— Phys.org (@physorg_com) October 24, 2018
On Earth, perchlorates are created by photochemical reactions that are fueled by the sun. While there aren’t many of these natural perchlorates here, they can still be found in some areas like Antarctica’s dry valleys, the Atacama Desert of Chile, and the Qaidam Basin on Tibet Plateau. However, there are 10 million times this number on Mars than would normally be assumed to exist simply through basic photochemistry.
While it was surmised that lightning might be able to trigger perchlorates, in their new research, Wang and other scientists created an experimental simulation which showed that under these conditions, perchlorate was found at a rate 1,000 times greater than could be expected through photochemistry.
Every two years on Mars there is one massive global dust storm, with more localized dust storms occurring every one year on average. According to Wang, “This study opens a door. It demonstrates the strong oxidation power of electrons in electrostatic discharge process generated by dust events. It suggests that electrostatic discharge in Martian dust events can affect many other redox processes in the Mars atmosphere and Mars surface and subsurface, such as iron and sulphur systems as well.”
The new study which demonstrates that perchlorates on Mars can be formed through electricity found in dust storms has been published in Earth and Planetary Science Letters.