Caves as Initial Footholds on Mars

sanman · 2013-01-03 21:24:07

How can we find caves on Mars? What remote sensing technologies should we use to do this?

The earliest human ancestors didn't start out building their own hovels with thatched roofs. They lived in caves, making use of existing natural features for safe dwelling. Logically, during the early period of Mars settlement, such natural features could be very invaluable, and save on effort in building or bringing in your own shelter.

What would be the ideal types of caves that would be most useful for our needs? What kinds of features should we look for to identify such ideal caves?

Once we identify the best possible caves to make use of, then what would we need to do to convert these natural formations into robust living accommodations, in the most efficient way with the least effort and quickest turnaround?

What would we have to bring with us from Earth in order to accomplish this?

Void · 2013-01-19 00:51:45

I would want to figure out how to find lava tubes submerged under ground ice. Tunnel down to them through the ice, and set up shop. I would think that they would already be sealed by ice (Lava tubes have cracks), so they could be pressurized. They could be warmed to a reasonable temperature that does not melt ice, and building methods more similar to what we do on Earth could be used, to provide accomodations for living and for factories.

Finding them would be hard, and I suppose it would almost have to be at high lattitudes.

Could some type of rover with a sonar which pings into the ice work to search for them? I suppose you would have clues from the geology, to know that you were in a location where ice lies above a possible ancient volcanic location.

Last edited by Void (2013-01-19 00:53:37)

louis · 2013-01-19 04:22:51

Caves sound superficially attractive but I am not sure they really are a good option for early settlement.

Firstly, you have to "find your cave" and that is no mean feat. It will probably require thorough robot exploration over several years: all very expensive and unnecessary.

Even if you have a cave, you can't just go set up in it. You would have to have a habitat unit WITHIN the cave. There may well be venting and ventilation issues (e.g. dust accumulation that need to be addressed).

Caves are inherently dangerous places - roof falls, flooding and so on, none of which can be ruled out. On Mars you would have to be v. sure of your location, so that the entrance did not become blocked by a sand storm.

The only major advantage of a cave is providing protection against radiation. But we have ways of ensuring that protection is delivered outside in the open - most easily by simply heaping regolith over the habitat unit. Also, my favoured method of construction (trench and cover) gives you a lot of the advantages of caves with none of the problem.

Longer term I can see there may be some advantages to caves as natural structure, particularly if we could create safe, pressurised atmospheres in them. But we need to get plenty of humans there on the ground first.

Void · 2013-01-19 12:43:53

Lewis said:

The only major advantage of a cave is providing protection against radiation. But we have ways of ensuring that protection is delivered outside in the open - most easily by simply heaping regolith over the habitat unit. Also, my favoured method of construction (trench and cover) gives you a lot of the advantages of caves with none of the problem.
Longer term I can see there may be some advantages to caves as natural structure, particularly if we could create safe, pressurised atmospheres in them. But we need to get plenty of humans there on the ground first.

I agree, that the probability of a lavatube being located at an advantage, and particularly finding one under ice is currently diffacult. But the person who initiated this thread had a specific set of requests, and I have tried to move forward on them.

However, I am thinking of a network of ice caves, sandstone caves, and lava tube caves (If lava tube caves are convenient).

The lavatube caves would be natural. The ice caves and sandstone caves would be manufactured, slight chances exist for sandstone caves, but in their natural state they would likely not be of much value.

For ice caves, I am thinking of skyscrapers embeded in ice, with airlocks on the top, and connection to a sandstone deposite below. The ice walls would help hold the structure's pressurization needs.

Here are some links to artificial sandstone caves. For some sandstone, but not all, they might be possible:

http://www.environmentalgraffiti.com/ar … ve-temples

http://www.faribaultdairy.com/tourthecaves/

http://news.nationalgeographic.com/news … mers-hole/

http://www.google.com/search?q=californ … 93&bih=491

http://en.wikipedia.org/wiki/Wine_cave

http://www.napanow.com/wine.caves.html

I have no expectations, that we would want to first settle the high lattitudes, unless a submerged cave of convenience offered some unusual advantage, which I do not expect.

However, for all the intentions of terraforming Mars, it is also not practicle in my opinion to have a strong efficient Earth type habitat which covers a large scale of area in any realistic time frame.

We need a plenum. On Earth our plenum is the surface with a suitable atmosphere above it.

That will not be available on Mars any time soon.

Mice and other rodents, are helped by a snowfall in the winter. They are small and will freeze without it.

I guess what I am looking for is a large scale network which can be expanded to great expanses. I have said verticle ice caves filled with a verticle building. I have also said sandstone caves which could be stable if the right sandstone pockets existed, and I think some will. Beyond that for bulk transportation, on long distances, I suppose surface trains and roads with robotic trucks make sense. However it might also be possible to have horrizontal subways in the ice (Which will require supports), or maybe even in the sandstone, and in some cases harder rock, which may not require support.

Solar collectors would need to be on the surface of course with robots to construct them from parts manufactured. (Above or below, depending on economics). The verticle buildings in the ice would be the location to route power cables down to the caves.

In this case your water supply would be mined, either tunneling, or open pit.

I believe that solar collection will continue to become more efficient, and also lighting devices would be better. So, it is not unreasonable to me to suppose that in some sandstone caves, you could have trees, most likely for fruit. The trees would also be for human happyness. The spectrum of light could be only that that the trees use when people are not visiting, but better light could be provided for those occasions when people want it.

Even more efficient will be chemosynthesis, where chemicals manufactured can drive a biological system. Mushrooms will grow on soil contaminated with oil for instance. I expect that the oil would have to be manufactured.

A harder to handle method would involve Hydrogen and Oxygen, which could be obtained from water and energy.

And of course their can be greenhouses on the surface as well.

I guess I have deviated from the "Initial Foothold" theme, but maybe "Initial foothold of a planetary civilization could be supposed".

I beleive that manufacturing materials for building a large scale plenum on the surface could be largely unprofitable, and sandstone under ice may exist in large quantities. I think that large scale of pressurized space many be more profitable with this scheme.

Last edited by Void (2013-01-19 13:07:04)

tahanson43206 · 2020-11-09 19:48:34

This topic is one of four with the word 'cave' in the title.

The talk about possible life on Mars at the Mars 2020 Convention included mention of as many as 1000 sites which might be openings to caves on Mars.

0:02 / 27:26
Dr. Carol Stoker - Potential Habitats for Life on Mars - 23rd Annual Mars Society Convention

A direct link to the talk is here:
https://www.youtube.com/watch?v=04Ri-OF … AF&index=6

A comment that caught my attention was the suggestion that the helicopter to be tested at Mars after a safe landing of Perseverance might be an ideal instrument to explore caves. It may not be possible to stretch the first test vehicle to that extent, but if the test is successful, it seems reasonable (to me at least) to suppose future versions of the helicopter could be given greater range and perhaps autonomy.

(th)

SpaceNut · 2020-11-09 20:18:45

Much depends on lighting and size of the caves entrance and shape as to whether it could explore such a place. It would not be until other objectives are complete that any decision would be made by nasa to take such an endeavored on until then.

Caves do give the shelter from radiation but we must be able to seal it as well to allow it to be a habitat....

tahanson43206 · 2020-11-10 06:41:11

For SpaceNut re #6

Here I'm thinking of a recent post by GW Johnson about creating a habitable volume inside asteroid Bennu.

GW Johnson suggested using a lightweight material capable of holding pressure, to provide an atmosphere suitable for humans taking refuge inside Bennu in case of a radiation event.

The same mechanism could work well on Mars inside a cave. It is not necessary to seal the entire cave.

***
Regarding lighting as a factor for operation of a drone exploring caves on Mars .... human cave explorers (I am reporting from seeing video) use head lamps to illuminate their surroundings. A Mars helicopter "explorer" might employ LED lighting to assist the onboard sensors to map the features of the cave as it moves about. I would expect flying conditions to improve as the vehicle descends. There would be little to no wind to disturb the flight, and air pressure would increase (albeit only slightly) as the vehicle descends.

(th)

SpaceNut · 2020-11-10 17:49:58

For caves while they might have the empty space within that might not be a regular round cavity but one that can and might be irregular shaped. The inflatables so far are very regular in that they have a thickness and general round shape. If inflation where to cause an out of round shape contact then it could break or be punctured by the sharp rocks. Another thing is movement while its somewhat isolated by the material thickness its still can see that force along a larger area of contact to those sharp rocks. To remove these we must pad the floor surface before even attempting to do any thing else happens.
The seal is the door or airlock which we enter and exit from the habitat space created by the inflatable being within the cave.

tahanson43206 · 2020-11-10 18:32:59

For SpaceNut re #8

I hope an artist is inspired by the word picture in your post!

I can see (in my mind's eye) something like an Airstream trailer tucked into a cave cavity a short distance from the entrance.

The Apollo astronauts got to spend a couple of days in an Airstream on the deck of the carrier where they were airlifted after landing.

An Airstream is not designed to hold pressure, but a version of the shape would (presumably) work well on Mars.

So an artist's rendering of your word picture might show an Airstream inside a cave on Mars. There is no way of knowing what the interior of the cave might look like, after millions of years waiting for humans to arrive. The imagination of the artist would have free reign, until the helicopter goes visiting.

(th)

SpaceNut · 2020-11-11 18:21:36

Assemble a wheel carriage to a Cygnus module and we are there in a pressurized habitat already proven to work.
This would be simular to the Chariot for Nasa's moon missions.

Mars_B4_Moon · 2021-09-10 07:32:58

Astronomers discover natural shelter on Mars against radiation
https://www.wionews.com/science/astrono … ion-411572

Martian cave entrances may offer a life-friendly radiation shield
https://www.newscientist.com/article/22 … on-shield/

I normally don't bother much with video games anymore, I think they are mostly a waste of time...but....

At one time I was reading that Musk was asking Video Game developers about their ideas on exploration, I first thought it ridiclous and Musk wass just being his usual quirky self. then I seen at how much effort and production that goes into these modern Xbox and Playstation style games, there is a new game ‘Surviving Mars’ there are adverts online, it is free with something or offered on some other site. Some of these games seem silly but this one could have something to offer with interesting modesl and visuals of a survival space sim game. In video clips of the game they seem to have put the bases subterranean, most of the stuff is underneath or inside caves or the paths and homes and factories all seem to be beneath the surface, most of the peoples are put into seperate colony into caves and lava tubes under the surface. There are dome and surface farms but also a clever use of caves, they say it features asteroid mining, it looks like an expensive game production with good voice actors and animation.
https://worthplaying.com/article/2021/8 … s-trailer/
https://www.gamingonlinux.com/2021/08/s … -asteroids

The Video Game Design of the suit reminds me of the real life SpaceX designs

Mars_B4_Moon · 2021-11-28 07:30:04

New Generation of Indoor Farming
https://spinoff.nasa.gov/indoor-farming

NASA is training human-like robots to explore caves on Mars
https://www.cbsnews.com/news/nasa-human … aves-mars/

SpaceNut · 2021-11-28 09:40:10

If we do not have the boring equipment to make our underground then we need the items which once we find a select cave to be able to make it safe and protective for man to use it.

Yes inside such created structure we need to produce air and food but what about a source of water?

So can anyone itemize what we would need after a cave double door interface air lock to seal man into a protective environment?

Mars_B4_Moon · 2022-04-17 07:55:02

Underground Living on Mars.

https://eptle.wordpress.com/2022/04/17/ … g-on-mars/

some other discussions "Underground vs Above Ground" (Both actually)
https://newmars.com/forums/viewtopic.php?id=8903 Cave Entrances found on Mars https://newmars.com/forums/viewtopic.php?id=5289
'Mars City Nuwa' https://newmars.com/forums/viewtopic.php?id=10006 Use of caves-discussion https://newmars.com/forums/viewtopic.php?id=7365

Store of fuels?

Living inside Mountains / Caves on Mars?
https://newmars.com/forums/viewtopic.php?id=8033
Void wrote:
Liquid fuels such as "Ethanol" can be stored in tanks for long periods of time. Stockpiled.
Oxygen can also be stored in tanks, but another way is to utilize caves either originally natural or caves totally manufactured, to store Oxygen.
Some of these liquids could be burned in internal combustion engines, or fuel cells and that also could produce electricity inside the caves. The electricity could provide lighting in side of the caves.
The Carbon Monoxide is a gas of course, and a poison to mammals including humans. I am not saying don't use it as a fuel for machinery, but it could also be placed in sections of cave, with water in it. Microbes would then be able to consume it, and also use the water as Oxidizer, and that can release Methane. So, a potential source of Methane, which can loop back to the liquid fuels process.
Of course all of this is likely to be rooted in solar power at it's foundations.

Last edited by Mars_B4_Moon (2022-04-17 07:57:49)

Mars_B4_Moon · 2022-10-26 05:37:48

Emptied out Lava Tubes on the Moon and Mars giving Living Space and finding one broken by an impact crater?

Concept for Lunar Caves

40 min talk

https://www.youtube.com/watch?v=kdv_V8Hu9kw

,

Mars Underground
http://www.rocagallery.com/mars-underground
Why cave-dwelling makes sense on the red planet

,

https://www.esa.int/Our_Activities/Prep … unar_caves

Planetary Cave Exploration Progresses
https://eos.org/science-updates/planeta … progresses
Terrestrial caves offer scientific and engineering insights and serve as testing grounds for future forays by humans and robots into caves on other worlds.

Caves on Earth form by a variety of processes. Volcanism can leave behind lava tubes or gas-inflated chambers, fluid dissolution hollows out caverns in subterranean rock, and wind and weather can mechanically erode cliff or seaside caves, for example. Because many of these same processes operate on other planetary bodies in our solar system, it’s likely that at least some of these bodies host their own caves.
To date, more than a thousand possible cave entrances have been identified on Mars, and hundreds have been resolved on the Moon using high spatial resolution cameras such as the Mars Reconnaissance Orbiter’s High Resolution Imaging Experiment (HiRISE) and the Lunar Reconnaissance Orbiter Camera (LROC). Meanwhile, other identified subterranean access points include two cryovolcanic vents on Pluto; ice fissures on the moons Enceladus, Europa, Titan, and Triton; and several conspicuous holes at the bottoms of impact craters on Mercury.

Mars Astrobiological Cave And Internal Habitability Explorer (MACIE): A New Frontiers Mission Concept
https://astrobiology.com/2021/05/mars-a … ncept.html

Plus can you land your craft inside a 76 meters or 250 ft diameter hole

China Eyes Lunar Underground Volcanic Caves to House Astronauts on the Moon
https://www.sciencetimes.com/articles/4 … s-moon.htm

SpaceNut · 2022-10-26 19:54:17

A close cousin to this topic is Lava and Ice tubes

Calliban · 2022-12-07 17:23:46

Living underground.
https://m.youtube.com/watch?v=wxozN_ussjw

These are all places that make no attempt to hide the fact that they are underground, because that is part of the novelty.
On Mars, people will be living underground all of the time, aside from brief forays to the surface. Underground habitats cannot resemble dark, damp caves. Instead, synthetic sky will be used to provide light. Aside from agricultural areas which need sunlight, all human habitations can be located underground. To build a base, we find a mountain and excavate the volume needed from solid rock using pneumatic drilling.

kbd512 · 2022-12-07 18:41:29

Calliban,

The cavern, however dark it may initially appear, is actually quite beautiful. It looks like some sort of natural sculpture / industrial art. If there were places to explore on the base, I'd have no issue with living there permanently. My kids would love that place. We should excavate such places on Mars, merely to give the people living there places to explore in relative safety. It reminds me of the Natural Bridge Caverns in Texas, which I visited multiple times as a child and young adult. That was one of my favorite places to go. If we could live in a place like that on Mars, that would be awesome.

Calliban · 2022-12-08 13:35:06

It is impressive. The video mentions that it took 200 years to fully excavate. But that appears to have been entirely using hand tools. If we could find a Mars mountain made out of soft sand stone, then huge volumes could be excavated quickly using mechanical diggers.

Here is a video about Coober Pedy in the Australian outback. This is just a village. An underground city would need a lot more planning.
https://m.youtube.com/watch?v=ZY2pvCldIi0

Last edited by Calliban (2022-12-08 13:39:15)

tahanson43206 · 2022-12-08 16:01:15

For anyone .... was there any mention of how air flow from the surface is managed in the salt mine complex? It is implied by all the activity in the evacuated space, but if it was mentioned, I missed it.

In the case of Mars, there would be more involved than just drawing fresh air in from the surface. However, the volume of air to be moved would (I presume) be the same, so knowledge of how the current managers of that facility deliver clean air would be interesting.

(th)

Calliban · 2022-12-09 12:46:29

TH, it wasn't mentioned. It is unlikely that natural ventilation could be relied upon given the occupancy of the space.

Two additional videos. The first, concerning an underground bunker in Finland. The second, discusses Cheyenne mountain.
https://m.youtube.com/watch?v=vFFhejGOTiM
https://m.youtube.com/watch?v=nAHBekea2Fc

Last edited by Calliban (2022-12-09 12:48:54)

tahanson43206 · 2022-12-09 16:12:19

For Calliban re #21

I'm back from viewing the Helsinki video ... That is just amazing (to me for sure!) ... accommodation for 700,000 people in case Russia attacks. Russia has (obviously) been an existential threat to Finland for a long time! That threat was enough, and lasted long enough, to impel the people of that Nation to exert themselves far beyond what mere Capitalism could have done.

The video did show air equipment, but the presenter did not dwell on the subject, and for security reasons, I can understand reluctance to reveal much about it. However, by deduction, I would expect the system would be designed for recirculation within that huge underground volume, and thus (if my guess is correct) this would be a very ** good ** model for Mars, as you pointed out.

I'm planning to check out the Cheyenne Mountain video this weekend.

Thanks again for a most interesting set of links in support of this topic.

(th)

Calliban · 2022-12-09 17:30:26

How to cut through solid rock.
https://theconstructor.org/practical-gu … 284/?amp=1

According to this source, this is most effectively achieved using a combination of pneumatic drilling and blasting. Pneumatic drills on Mars can use compressed CO2, or potentially, could be combustion driven using a mixture of CO2, O2 and H2 or CH4. In place of explosives, we could use steel tubes containing a mixture of cold, compressed oxygen and methane. The gas within the tube would be ignited by spark plug.

There are plenty of existing excavators, trucks and loaders that come in under the Starship payload capacity.
https://www.cat.com/en_US/products/new/equipment.html

I have been thinking of ways that we could work excavating tunnels and remove excavated rock within a pressurised environment. One way is obviously to have a vehicle airlock that allows rock to be removed from a pressurised space to outside. Another is to load the rock into a tube, which is sealed by a solenoid operated flap on the outside during loading and a door on the inside. When the tube is full, the inner door is sealed, the solenoid holding the outer flap shut is released and a compressed air charge blows the rock out of the tube. Being able to work in a pressurised atmosphere allows Earth based mining equipment to be used with minimal modification.

I have no idea how long it would take to excavate a volume comparable to the Romanian salt cave. But the interesting thing about carving a habitat out of rock is that no structural materials are needed other than the rock itself. Also, after an initial thermal soak time, no heating woukd be needed. The insulation provided by >30m of rock on all sides, is equivelent to at least 1m of rockwool insulation. So a mixture of equipment wasteheat and body heat would keep the hab warm once the stone is warmed up.

In the Expanse TV series, underground streets on Ceres were carved out tunnels, with condos being carved out spaces within the tunnel walls. I can see people being happy living in environments like this. But I don't have a good idea as to how practical it would be to do this using excavators shipped to Mars. How long would it take to dig out tunnels like those shown below?

Last edited by Calliban (2022-12-09 18:07:45)

Calliban · 2022-12-09 18:22:07

Medina level

A condo apartment

Last edited by Calliban (2022-12-09 18:26:07)

Void · 2022-12-10 12:37:12

I have just made a fair attempt to review your provided materials in the last few posts. I would like to try to contribute, as I think much good has been provided, and Mars likely has a lot to offer in this type of activity. If it appears that I am driving other members away, then let me know, I can fade more into the background.

Query: "Sedimentary rocks on Mars"

Query: "Rocks on Mars:: Basalt, Shale, Sandstone Conglomerate"

https://geology.com/stories/13/rocks-on-mars/
Quote:

Rocks on Mars
A variety of rock types and sediments have been found on Mars.
Many are similar to rocks on Earth.

Where Mars does not offer forests, it seems possible that it has been laying down layers in places for the life of the planet. This of course is different than the Earth where plate tectonics recycles the crust.

Billions of years of sedimentation is something very different.

Per its name insight has to some insights to offer: https://www.space.com/mars-subsurface-m … ent%20lava.
Quote:

NASA Mars lander makes 1st ever map of Red Planet underground by listening to winds
By Tereza Pultarova published November 23, 2021
The sound of wind reveals details of Martian subsurface.

Image Quote: https://cdn.mos.cms.futurecdn.net/BmXUQ … 200-80.jpg
Quote:

The surprising sedimentary layer, the origin of which is still a mystery, is located 100 to 230 feet (30 to 70 m) below the Martian surface, sandwiched between two solidified layers of ancient lava.

The layer above the upper lava layer, is apparently not well cemented, and does not display much water/ice.
In a way, that could be good as it might be relatively easy to get down to the top lava layer.

Quote:

The researchers compared the two lava layers embracing this sediment with previous studies of geology of nearby craters. This data enabled them to place the origins of those layers into two important periods in Mars' geological history some 1.7 billion and 3.6 billion years ago.
On top of the younger lava layer, just below the surface regolith, is an approximately 50-feet-thick (15 m) band of rocky material likely stirred up from the Martian surface by a past meteorite impact that then rained back down to the planet's surface.

So, I think that some methods exhibited by the other members to get though the top layer and also the 1.7-billion-year-old lava layer would be good. Then once through, perhaps the sediment layer could be carved, still leaving plenty of supports to hold up the upper lava layer.

What is between the two lava layers, is unknown, but perhaps some of it is sandstone.

Query: "Cutting sandstone blocks"

General Response: https://www.bing.com/search?q=Cutting+s … 232b4adac6

Specific Response: https://www.hunker.com/13401265/tips-fo … -sandstone
Quote:

Tips for How to Cut Sandstone
By CHRIS DEZIEL, BUILDING CONTRACTOR
Updated SEPTEMBER 3, 2022

Quote:

Sandstone is mined from quarries and delivered in slabs and bricks of varying thicknesses. If you want to use it for a home project, you'll have to cut it at some point, and there are two ways to do this. One is with a hammer and bolster chisel, and the other way is to use a saw. A slab saw is recommended, although a table saw or worm-drive circular saw will also work. In all instances, you need a diamond cutting blade.

So, not only to make a space underground, but perhaps to also make slabs and bricks, and perhaps some other things out of the materials removed.

Of course, not all of Mars will be like what is under the insight lander, and that is a good thing, so that other things might be employed and created.

I think this is enough from me for a bit.

Done.

Last edited by Void (2022-12-10 13:18:20)

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#1 2013-01-03 21:24:07

Caves as Initial Footholds on Mars

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Re: Caves as Initial Footholds on Mars

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