The salty liquid water on Mars
Click for full unannotated image.
The map above, reduced and annotated by me, comes from a new science paper that has attempted to model where on Mars we might find liquid very salty water, based on the planet’s known temperature and make-up. From the press release:
The team of researchers used laboratory measurements of Mars-relevant salts along with Martian climate information from both planetary models and spacecraft measurements. They developed a model to predict where, when, and for how long brines are stable on the surface and shallow subsurface of Mars. They found that brine formation from some salts can lead to liquid water over 40% of the Martian surface but only seasonally, during 2% of the Martian year.
“In our work, we show that the highest temperature a stable brine will experience on Mars is -48°C (-55° F). This is well below the lowest temperature we know life can tolerate,” says Dr. Rivera-Valentín. “For many years we have worried about contaminating Mars with terrestrial life as we have sent spacecraft to explore its surface. These new results reduce some of the risk of exploring Mars,” noted Dr. Alejandro Soto at the Southwest Research Institute and co-author of the study. [emphasis mine]
I have added a red rectangle to the map, showing the candidate landing zone for SpaceX’s Starship. This paper illustrates again that this choice is a good one. We know from other research that there is a lot of ice very close to the surface here. This research indicates that for a little less than one percent of each year, some of that ice will turn to liquid brine.
Whether it will be easier to process the ice or the brine into drinkable water remains unknown. This location however will give future colonists that option.
That this model also suggests that there is little risk of contaminating Mars accidently with terrestrial life is really not a surprise. All the research of Mars for decades has found that it is inhospitable to terrestrial life. This data however is further confirmation, and tells us once again that worrying about contaminating the planet is a irrelevancy. For scientific reasons some precautions should be taken, but to spend a lot of time and money sterilizing the spacecraft we send there will be a fool’s errand. For humans to settle Mars will require a very very high level of engineering and adaptation, something we humans are very naturally good at, but something that shouldn’t be burdened with unnecessary tasks or restrictions.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Click for full unannotated image.
The map above, reduced and annotated by me, comes from a new science paper that has attempted to model where on Mars we might find liquid very salty water, based on the planet’s known temperature and make-up. From the press release:
The team of researchers used laboratory measurements of Mars-relevant salts along with Martian climate information from both planetary models and spacecraft measurements. They developed a model to predict where, when, and for how long brines are stable on the surface and shallow subsurface of Mars. They found that brine formation from some salts can lead to liquid water over 40% of the Martian surface but only seasonally, during 2% of the Martian year.
“In our work, we show that the highest temperature a stable brine will experience on Mars is -48°C (-55° F). This is well below the lowest temperature we know life can tolerate,” says Dr. Rivera-Valentín. “For many years we have worried about contaminating Mars with terrestrial life as we have sent spacecraft to explore its surface. These new results reduce some of the risk of exploring Mars,” noted Dr. Alejandro Soto at the Southwest Research Institute and co-author of the study. [emphasis mine]
I have added a red rectangle to the map, showing the candidate landing zone for SpaceX’s Starship. This paper illustrates again that this choice is a good one. We know from other research that there is a lot of ice very close to the surface here. This research indicates that for a little less than one percent of each year, some of that ice will turn to liquid brine.
Whether it will be easier to process the ice or the brine into drinkable water remains unknown. This location however will give future colonists that option.
That this model also suggests that there is little risk of contaminating Mars accidently with terrestrial life is really not a surprise. All the research of Mars for decades has found that it is inhospitable to terrestrial life. This data however is further confirmation, and tells us once again that worrying about contaminating the planet is a irrelevancy. For scientific reasons some precautions should be taken, but to spend a lot of time and money sterilizing the spacecraft we send there will be a fool’s errand. For humans to settle Mars will require a very very high level of engineering and adaptation, something we humans are very naturally good at, but something that shouldn’t be burdened with unnecessary tasks or restrictions.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
There are a class of organisms – besides Elon Musk – known as extremophiles that might find Mars hospitable https://en.wikipedia.org/wiki/Extremophile so we might be surprised. Maybe something thrives in cold brine….(sounds perfect for cooling the colony)
Nevertheless, it would be smart to land an automated biological test lab on the Mars surface to check how Earth organisms survive being exposed to the Mars environment. The primary concern is the unknown unknown. Prefer to expose a Petri dish of Earth cells and see how they fair compared to an astronaut. But yes, most folk are like Buck Rogers and wanna go there now.
While we’re at it, perhaps we need a little testing of how human biota mutate during the trip to and from Mars. This means we need to just expose outside the van Allen belt a set of human gut microbes, preferably without the human having to do this for years. And then maybe retrieve and analyze or do analysis in situ, whatever is cheaper. Mainly to examine the effect of galactic cosmic rays. On the human as a whole, they might recover form damage at a human cell level. But the microbes are a little different.
Mars always seems to hold surprises for us. I’m surprised at the possibility of such widespread brines.
I was also surprised at the results of some extremophile lichen experiments in simulated Mars conditions.
https://www.astrobio.net/extreme-life/lichen-on-mars/
http://journalofastrobiology.com/Mars15.html