The Related Press studies that “water could also be extra widespread and up to date on Mars than beforehand thought, based mostly on observations of Martian sand dunes by China’s rover.” A paper printed in Science suggests skinny movies of water appeared on sand dunes someday between 1.4 million years in the past and as lately as 400,000 years in the past — or even perhaps sooner:
The discovering highlights new, probably fertile areas within the hotter areas of Mars the place circumstances may be appropriate for all times to exist, although extra examine is required…
Earlier than the Zhurong rover fell silent, it noticed salt-rich dunes with cracks and crusts, which researchers mentioned doubtless had been combined with melting morning frost or snow as lately as just a few hundred thousand years in the past… Situations throughout that interval had been just like now on Mars, with rivers and lakes dried up and now not flowing as they did billions of years earlier…
The rover didn’t instantly detect any water within the type of frost or ice. However Qin mentioned pc simulations and observations by different spacecraft at Mars point out that even these days at sure occasions of 12 months, circumstances could possibly be appropriate for water to look… Small pockets of water from thawing frost or snow, combined with salt, doubtless resulted within the small cracks, arduous crusty surfaces, free particles and different dune options like depressions and ridges, the Chinese language scientists mentioned.
House.com explains precisely how the invention was confirmed:
The laser-induced breakdown spectrometer (MarSCoDe) instrument onboard the rover zapped sand grains into millimeter-sized particles. Their chemical make-up revealed hydrated minerals like sulfates, silica, iron oxide and chlorides… Researchers say water vapor traveled from Martian poles to decrease latitudes like Zhurong’s spot just a few million years in the past, when the planet’s polar ice caps launched excessive quantities of water vapor, due to a special tilt that had Mars’ poles pointed extra instantly towards the solar. Frigid temperatures on the wobbling planet condensed the drifting vapor and dropped it as snow removed from the poles, in response to the newest examine.
Mars’ tilt modifications over a 124,000-year cycle, so “this presents a replenishing mechanism for vapor within the ambiance to type frost or snow at low latitudes the place the Zhurong rover has landed,” Qin advised House.com. However “no water ice was detected by any instrument on the Zhurong rover.” As an alternative, in the identical means that salting roads on Earth melts icy patches throughout storms, salts in Martian sand dunes warmed the fallen snow and thawed it sufficient to type saltwater. The method additionally fashioned minerals corresponding to silica and ferric oxides, which Zhurong noticed, researchers say. The saltwater, nevertheless, did not keep round for lengthy. Temperatures on Mars swing wildly and spike within the mornings between 5 a.m. and 6 a.m., so the saltwater evaporated and left behind salt and different newly fashioned minerals that later seeped between the dune’s sand grains, cementing them to type a crust, in response to the examine…
“The phenomenon was documented at one website, however it ought to be relevant to a reasonably large fraction of Mars’ floor at related latitudes,” Manasvi Lingam, an assistant professor of astrobiology on the Florida Institute of Know-how who wasn’t concerned within the new analysis, advised House.com.
For the reason that rover discovered water exercise on (and in) salty Martian dunes, the researchers now recommend future missions seek for salt-tolerant microbes , and are elevating the opportunity of “extant life on Mars.”
