The pit caves of Mars: Can humans someday live in them?
It has been more than four months since my last report on the pits of Mars. Time to do another.
The collage to the right shows the four different pits photographed by the high resolution camera of Mars Reconnaissance Orbiter (MRO) since October. The links to each image are:
- Number 1: full image here.
- Number 2: full image here.
- Number 3: full image here.
- Number 4: full image here.
Like almost all the cave pits so far found on Mars, all are in the Tharsis Bulge of giant volcanoes to west of Valles Marineris. The overview map below shows these pits in the context of every other pit in this region that I have featured on Behind the Black.
The black boxes indicate the location of previously feature pits. The numbered white boxes show today’s pits. The first is on the south flank of Pavonis Mons, the middle volcano in the string of three volcanoes in this bulge. The last three are on the flanks of Arsia Mons, the southernmost volcano of this string.
In their full photos, all four pits are all by themselves on a relatively featureless lava plain, though images #2 and #4 appear to be centered in very shallow depressions that hint of an underground lava tube flowing downhill from the peak of Arsia Mons. These pits could thus be skylights into that tube.
All of the photos however do not have enough resolution to tell us whether there are any underground passages moving away from them. For all we know, there are no lava tubes here, only vertical pits that go nowhere.
The plethora of pits in this region of Arsia Mons however pose an interesting dilemma for future Mars colonists. Most of the easily accessible ice near the surface on Mars is found in in latitudes higher than 30 degrees. All of these pits however sit in latitudes from the equator (just south of Pavonis Mons) to about 19 degrees south. None are in those wetter regions.
At the same time, there is some evidence suggesting past glacial activity on the western slopes of Arsia Mons. Moreover, the atmosphere above these western slopes also sees seasonal clouds, suggesting the release of water. Combined, this data suggests (though we don’t yet have any direct evidence) that there might be water ice here, but buried deep underground and only likely reachable from these pits.
Thus the dilemma. For the early settlers, it makes sense to go to the higher latitudes in the northern lowland plains, where lots of ice will be available very close to the surface. This is why SpaceX has chosen the plains of Arcadia Planitia for the first landing site of its Starship spaceship.
Yet, Arcadia Planitia has disadvantages. Because no caves are so far known in these plains, early colonists will have to do a lot of work to live there safely. Either they’d have to build from scratch shelters that are also hardened against radiation, or they would have to dig down and create underground shelters. In either case the required labor and materials would be extensive and challenging for the first pioneers, arriving with relatively limited resources.
If there is water in the cave pits surrounding Arsia Mons, this problem will be solved. The colonists would only need to create an access road into these pits, seal the walls, and then fill them with atmosphere. The ground above them will shelter them from radiation.
But Arsia Mons has other problems. First, we don’t know if these pits have water ice, and even if they do, it is likely they have it in far less quantity than seen in the northern plains. Furthermore, because these pits are at high Martian elevations, the already thin atmosphere will be even thinner. It will likely be too thin to use for helicopter drones or gliders. That thin atmosphere will also make the environment harsher.
Which problem would you choose to deal with? In the northern plains, lots of water and atmosphere but no easy shelter. In the high volcanoes plenty of easy shelter, but little atmosphere, a harsher environment, and questionable water resources.
In either case, for the human race this quandary is actually a grand and magnificent thing. Rather than fighting over scrapes of bread on Earth because we are poor and ignorant savages, future generations will be trying to bring life to this dead alien world by harnessing the human instinct for adaption and invention.
I suspect when all is said and done, centuries from now, we will find humans in both places, having figured out how to make the specific geology at each work for them.
————————-
For those interested in digging deeper into my earlier pit posts, you can find them all here, since 2018, with links to even earlier posts at the November 2018 post:
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
Hello Mr Zimmerman
Do you know how these are pits being found? manually or automated? I am guessing manually as they are slowly popping up. It might make sense to have a computer scan the images.
Could overlaying the pits on maps using other wavelengths CRISM, SHARAD, THEMIS show if there are caverns not too far below, by comparing (temperature or other reading) variations? Pseudorilles.
Thank you for posting. Nice to read good news.
jeff d: Most of these pits were previously spotted in wider lower resolution images, either from Mars Global Surveyor or the context camera on MRO. The scientists involved have been using MRO’s high resolution camera to document them all. It just takes time for the orbiter to get to them all.
Review my earlier posts on pits. You will come across my discussion of the original papers discussing these pits.
I would suggest that the cheapest way to verify the presence of lava tubes is to use an advance on the method used at the Marius Hills Hole, on the Moon. There, a sounding radar took several years worth of radar soundings of the lunar surface near to the Marius Hills Hole, whenever the spacecraft was above the site. Computer processing then put together the data from those soundings, resulting in a view of a lunar lava tube stretching for many kilometers.
Doing this on Mars would require a dedicated Mars Ground-Penetrating-Radar, specifically designed to find and characterize lava tube caves. An orbiting Mars GPR will have to be done in a mission prioritized for finding these settlement resources. It will need high power levels, and will need to have reboost capability to maintain its orbit close enough to the Martian surface that its resolution can show us what each lava tube’s internal characteristics are within its resolving power. It is likely its data levels will be extremely large, and will require laser transmission back to an Earth-orbiting receiver system. Multiple Bandwidths on the Radar may help find if solid ice is in the lava tubes, even with its low radar contrast with rock, compared to liquid water. Using it to get a global map of Martian ice layers would hardly be without value, even without lava tube work.
Getting this funded by NASA’s Science Directorate, with its own priorities emphasizing present Mars research programs, is improbable. However, once Starship is flying to Mars with some regularity, and people are looking for such living resources, then the data, once processed back here on Earth, may be salable to settlement groups. A single Cargo Starship could carry this to Mars orbit. It could be done within the sort of budget New Space start-ups are currently succeeding with in launch businesses.
“For those interested in digging deeper into my earlier pit posts, you can find them all here, since 2018:”
Great stuff Mr. Z. ! Thank you.
And ‘digging deeper into pit posts’ is very funny.
Tom Billings: While not explicitly looking for lava tubes, NASA has requested a new-start mission in the FY21 budget for the Mars Ice Mapper mission. It would use a ground-penetrating radar to map subsurface ice deposits. It’s being paid for by the manned spacecraft side of NASA specifically to look for underground water resources reachable during manned Mars missions.
I haven’t looked into it in enough detail to determine how useful it would be in the search for and characterization of lava tubes, but it’s a start. I also have not been able to find out if it made the final cut in the omnibus bill signed into law.
I highly recommend Mr. Zimmerman’s Leaving Earth. An exceptional read.
Happy New Year!
I am very dubious about manned space missions for many reasons (cost, hubris, risk, unresolved Earth problems that need such diverted funding, etc.) but i am naturally all for telescope & probe forays inspecting other celestial bodies.
I was wondering if you could give a thorough opinion about the Thunderbolts Project, “electric universe model”, and specifically this 2014 documentary which convincingly lays out the case (a solid hypothesis at least, with rich experimental evidence backing it) that the majority of surficial features of Mars were created by vast scales of electrical discharge. (i assume you have at least heard of this idea).
The electrical trace lab results compared to the high res. satellite imagery montages (along with the pleasing music) make this an engrossing viewing experience.
“Symbols Of An Alien Sky, episode2:
The Lightning Scarred Planet Mars” —
https://youtu.be/tRV1e5_tB6Y
I have some good amateur background in geology, and i do not see normally understood geological processes being able to explain the innumerable enigmas on Mars’ surface. Not at all.
As to your projections on human physical bodies & micro societies inhabiting & colonizing Mars (or any other planetary or lunar body beyond Earth) i cannot morally or financially support such projects — i fundamentally feel that we need to first solve our own spoiled nest syndrome, resolving the greed, injustice, conflict, habitat destruction, extinction crisis, pollution, unsustainable consumption, etc. here on one & only Mother Earth– before dropping a cent on such folly & hubris such as Martian ( or even lunar) colonization… in my humble opinion.
(i am also deeply distressed by the egomania of Elon Musk et al for pumping thousands of satellites into low earth orbit — i think this is among the greatest crimes against nature & humanity imaginable, and should be stopped forthwith, with technology deployed to remove every one of these orbiting devices of sky vandalism polluting our firmanent commons — at his expense.)
That said, it may be amusing to dream, so by all means– dream on.
Thank you.
Mr. B. wrote: “I am very dubious about manned space missions for many reasons (cost, hubris, risk, unresolved Earth problems that need such diverted funding, etc.) but i am naturally all for telescope & probe forays inspecting other celestial bodies.”
This is one of the largest reasons for commercial companies to perform space exploration. Rather than spend everyone’s money on exploration that may not produce results that everyone sees as productive, commercial companies will find profitable endeavors that cannot be denied as being productive.
Risk is all around us. People die while constructing dams, bridges, and buildings, but should we stop their construction because of the risk? Cars are dangerous, but we don’t stop driving. We cannot remove all risk from life. Instead, we manage risk. Just as these benefits outweigh the risks and costs, space holds benefits that have yet to be utilized. Moving that risk to commercial companies relieves governments and their populations from having to worry that they are funding and performing risky exploration.
Another problem with Mr.B’s opinion is the “unresolved Earth problems that need such diverted funding”
For one, it assumes that we are unable to solve multiple problems simultaneously. For two, it fails to consider the Earthly problems that we have been solving by using space. Weather forecasting now reaches more than a week in advance, while in the 1950s the weathermen were often wrong with their three-day forecasts. Inexpensive global communication is now available, without risking the lives of whales, who occasionally drown by entangling themselves on oceanic cables. We are now able to perform processes on Earth because we could only learn how to do them through research performed in space by human experimenters.
Weather forecasting now reaches more than a week in advance, while in the 1950s the weathermen were often wrong with their three-day forecasts.
This is not just a modern convenience — it’s a huge life saver! Take a look at the historical record for natural disasters in the 19th and early 20th centuries. Even in the United States hurricanes could strike without warning and kill thousands. In the third world it was often tens or hundreds of thousands. In addition to weather satellites, the Indian Resource Satellites, for example, have saved many tens of thousands by allowing the Indians to predict floods and famines before they occur.
mkent wrote: “In addition to weather satellites, the Indian Resource Satellites, for example, have saved many tens of thousands by allowing the Indians to predict floods and famines before they occur.”
Mentioning India reminded me of the satellite they put up in the 1980s that, among other things, allowed doctors in rural or remote areas video consultations with doctors at hospitals. “Have you seen this before, and what do we do about it?”
Seven billion people can get quite creative for the use of space.
Mr. B. said;
“i cannot morally or financially support such projects — i fundamentally feel that we need to first solve our own spoiled nest syndrome, resolving the greed, injustice, conflict, habitat destruction, extinction crisis, pollution, unsustainable consumption, etc. here on one & only Mother Earth– before dropping a cent on such folly & hubris such as Martian ( or even lunar) colonization… in my humble opinion.”
Many feel this way, and we all solve this problem one person at a time. We call it civilization.
Mother earths “nature” knows no other way to survive other than conflict. The big fish eats the small fish, the big trees shade the small trees unfairly, the mosquito is eaten by the frog which is eaten by the snake which is eaten by the bird which is eaten by the….
Most of the problems you promote was here before humans arrived, and will be here long after we are wiped out by the next pandemic. Your complaints to me are as silly as complaining about the weather, gravity, the sun too hot, or why snow is cold, and why hasn’t the miracles of science done anything about it yet? Ignoring that we live in the most wonderful productive time of earths history. Where every person has the luxuries available to them greater than any emperor of the near or distant past.
Although we have a population eight times that 100 years ago, our water and air has never been cleaner. Despite providing food and water for more people, waste and pollution is managed in a sustainable manner. (except in communist countries like China) trees cover more of the planet than 100 years ago. That’s progress.
What could a human race do for an encore? With each scientific marvel, comes responsibility and the advancement of capabilities to do something about earths condition which was beyond us just a few years ago. As far as I’m concerned, Elon musk is doing more to save this planet accidentally then all of the global warming cult members are doing to destroy it. (ultimately, in the climate change death cult, the only way to stop carbon consumption, is to kill the carbon consumers)
Logically, to escape all these problems that human nature has complicated your life with, you should be the first to volunteer to go to Mars. There, by necessity, most of these problems will no longer exist.
On Mars, the life of your community will be dependent on overcoming oxygen shortages, food shortages, living arrangements, waste product management, and every other issue that comes up that must be tackled and resolved with technological advances. The politics of fake science, on Mars, will not be tolerated, lives are at stake. The lessons learned there could very well save mother earth here. (as if it needed saving)
This is the challenge that will define if humans can prove themselves masters of their environment. Simply by creating one out of scratch, were none existed before. If it doesn’t work out, death will be their reward… But then we’re human, and we will try try again.
As for thunderbolts of the gods, it’s based on sound science but their imagination takes the conclusions too far. I’ve talked often about our Ice Age and the covering of cold moons/Mars with ice came from interstellar gas clouds thrown off by supernovas. As these clouds pass through our solar system blocking light from our Sun, it is possible, if they are thick enough, to conduct electricity equalizing the potential between the sun and the planets also causing the interstellar cloud to expand dissipating, or the lack of static charge to condense it, adding new mass to all the planets. Everyone who has watched a magnet pick up a car knows that magnetic fields are stronger than gravity fields and play a larger part in the construction of our galaxy than we realize.