Recent discoveries have shown that the Red Planet is much wetter than what everyone had previously thought. However, this wetness isn’t the type that boosts its potential to host life.
It’s impossible for liquid freshwater to exist on the Martian surface for longer time periods. It freezes or boils away rapidly into the thin air of the planet. But the super salty water, or brines, have a far lower freezing point, and thus can exist in liquid form for a longer time frame.
Over the years, scientists have observed evidence of these liquid brines existing on the planet as dark streaks on its slopes, as also indicated by NASA’s Mars Reconnaissance Obiter. It’s worth noting that not everyone believes that these recurring slope lines are because of liquid water.
Presence of liquid brines
Researchers used the information obtained from Mars’ atmospheric models and the measurements taken by the Mars-studying spacecraft to come up with a new model. As per the study, there is a possibility of liquid brines existing near and on the planet’s surface.
Based on this model, there is a possibility of 40% of the planet supporting liquid surface brines for around six hours continuously. This phenomenon is quite seasonal, with all the locations getting such brines for only around 2% of the Martian year. One Mars year is equivalent to 687 days on the earth.
The model further suggests that the near subsurface of Mars is also wetter, with brines existing 10% of Martian year, with a 3-inch depth. In fact, the Mars Express spacecraft of Europe had detected a huge lake under the south pole of the Red Planet, some time ago, suggesting the Mars’ deep subsurface could also be extremely wet indeed.
Is human life possible on the Red Planet?
However, the presence of these brines doesn’t promise the possibility of life on the planet, thereby answering an often asked question by people – If humans could permanently live on Mars one day? These brines seem ultracold with their maximum temperature is hovering around -55°F.
This was also confirmed by a new study that got published recently in Nature Astronomy on May 11, 2020. As per this study, the obtained results suggest the existence of (meta)stable brines on Mars’ surface as well as its subsurface. These make the planet uninhabitable as the water activities and their temperatures are outside of the tolerances known for terrestrial life.
There’s a silver lining nonetheless!
This recent discovery although upsetting for people who wanted to go on a vacation to Mars one day has a silver lining! As these brines don’t seem to support earth-like life, the missions sent to the planet in the future can investigate its areas without getting too concerned about contaminating them with the Earth’s microbes.
Mars was quite different at one point in time. The planet used to have plenty of surface water and thick atmosphere long ago. In fact, many scientists are of the opinion that the planet had a huge ocean covering almost 40% of its northern hemisphere once. However, things changed substantially around 4 billion years ago after Mars’ global magnetic field got lost, and the Sun’s particles started stripping the planet of its air.