Could Nuclear Powered Bulldozers Create a Habitable Cavity for a Mars Colony?

[darkdave3000]

TL;DR Summary

Can we dig 8km under the deepest areas of Mars will get us Mount Everest Pressures?

Digging 8km under the lowest point on Mars will get us Mount Everest conditions for air pressure.

I was thinking of two ways of doing said title:

1. Nuclear powered bulldozers working around the clock to clear away dirt on a low point on Mars such as https://en.wikipedia.org/wiki/Hellas_Planitia or a place with similar elevation preferably near the poles where there is lots of ice to feed the colony with rocket fuel, water and oxygen and even more CO2 gas. The lower gravity of Mars should allow us to build bigger dozers that has more mass and can accommodate a submarine style reactor.
2. Drop a hydrogen bomb down an 8km shaft to create a cavity and then clear away the sides to make it accessible as a gradual slope like a crater. Maybe a second bomb to do the clearing of the sides or nuclear powered dozers in option one above.

Would this be a practical means of starting a colony? We have experience with underground nuclear testing and we know that it can create cavities, maybe we don't even need to clear the sides and live in the cavity like a steep tear drop shape: https://en.wikipedia.org/wiki/Under...a/File:Nuclear_explosion_craters_schema_1.png https://en.wikipedia.org/wiki/Underground_nuclear_weapons_testing#:~:text=The extreme heat and pressure,cracked, and irreversibly strained rock.

There's a whole science in making a nuclear crater, why can't we use it on Mars to get air pressure?

Then we can not worry about decompression when we build. We can just carry scuba tanks with Oxygen and Nitrogen and breathe through a regulator.

If we use H bomb instead of pure Fission Bomb there should be less radioactivity problems. Lastly the gravity on Mars is 1/3 of Earth, wouldnt this make digging easier than say the Kola Borehole that is 10km deep?

 

[Baluncore]

I do agree that the first thing you should do when visiting Mars, is to dig your own grave. But being trapped at the bottom of an 8 km deep hole, that is filled with CO₂, will not make for convenient surface activity.

There are ways of blowing underwater bubbles or balloons with N₂ and O₂, that would have sufficient internal pressure for normal human activity, on or in the Martian surface. You might also consider living in a chamber, with a flexible fabric roof, weighted to 15 psi.

There is no need to dig a deep hole to increase atmospheric pressure. An Earth-like pressure could be gained more simply from a 30-metre head of water in a vertical pipe on the Martian surface. You could build and live in a cave system, underground, with a water column to maintain the positive pressure.

Nuclear explosions and deep holes are not a solution, they are a problem.

 

[darkdave3000]

I admit the initial work is messey but the wall sides dont have to be steep, they can be cleared to make a crater style settlement. Once done you can have the sun on your face without a pressure suit, you did have an oxygen tank carried by mountain climbers on everest and thats it, u can even plant trees and have liquid water lakes.

 

[Baluncore]

How does the hydrostatic pressure at the bottom of the hole, get back up to the surface, without the hydrostatic pressure falling again?
Or are you saying that you would live at the bottom of the hole, where the sun never shines?

Why dig a hole when you only need a skylight structure, that "weighs" on average 15 psi and is supported by your Earth-like atmosphere?

 

[darkdave3000]

I would propose nuking the bottom of the narrow shaft to create a large cavity and then nuking it again to clear the dirt around the mouth of the new crater so we get exactly that, a crater instead of a hole. And the bottom of this new crater you can plant trees have lakes and people walking around freely or naked even without fear of decompression but they will need to carry around oxygen tanks. By having real estate that allows people to work normally but in 1/3 gravity allows a lot of possibilities such as construction and manufacturing of more structures and units that can help to move dirt around and increase even more real estate for habitation. The plants can slowly transform the Martian atmosphere so that eventually you wont need the oxygen tanks. Beats living in caves, now you get sunlight on your face while wearing T-shirt or bikini and you can swim as the pressure is strong enough to sustain water in liquid form.

 

[Baluncore]

Once done you can have the sun on your face without a pressure suit, you did have an oxygen tank carried by mountain climbers on everest and thats it, u can even plant trees and have liquid water lakes.

The CO₂ atmosphere will saturate any water to make a strong carbonic acid solution. You will absorb CO₂ through your skin. CO₂ will sting your eyes. Your blood will become acidic, so you will suffer from acidosis even without breathing the "atmosphere".
https://en.wikipedia.org/wiki/Respiratory_acidosis

And the bottom of this new crater you can plant trees have lakes and people walking around freely or naked even without fear of decompression but they will need to carry around oxygen tanks.

... and a full hermetic pressure suit to protect them from the corrosive effects of the high atmospheric concentration of CO₂.

 

[darkdave3000]

I didn't know of such problems, you mean to say that the plants will not survive the CO2 in 35,000 Pascal pressure? What's your background? Biology?

I still think that the threat of decompression is much deadlier to deal with compared with the new conditions you mentioned though! It would still be much much safer living to deal with CO2 than a vacuum. And you can be more able to work and construct/manufacture things in hermetic pressure suits than fully pressurized ones! Would the plants be able to transform the atmosphere within the crater to a more Oxygen rich one? I've attached a concept illustration here in this reply, notice you can even dig into the side of the new crater and live in there so your home can also be a cave to do some geological studies and explore caves, but without the need for submarine style pressurized hatches. You can just have simple refrigerator style doors to seal out the CO2 outside. This would apply to houses too. Perhaps we will need green house for the lakes and trees initially before they terraform the atmosphere into a more Oxygen rich one. But again no risk of air being sucked out and evaporating the lake and killing all the trees and people instantly, if there is a leak it can be delt with in minutes or hours instead of needing to be delt with in seconds to save lives.

You can also extend this ecosystem by excavating sideways along the ground without going deeper to create a canyon of habitable zone, like a river of life. In the top down illustration there is a grey line representing a pipeline from a source of water ice in the pole where there is a fission reactor melting it 24/7 and using the water as a coolant before piping it to the "crater of life" where a "river of life" extends from it due to horizontal bulldozing by fission reactor powered bulldozers working round the clock too.

 

[Drakkith]

Would the plants be able to transform the atmosphere within the crater to a more Oxygen rich one?

No. The oxygen will diffuse into the atmosphere and be spread throughout the planet.

Lastly the gravity on Mars is 1/3 of Earth, wouldnt this make digging easier than say the Kola Borehole that is 10km deep?

The Kola Borehole is only about a meter across! You're talking about moving something on the order of billions of cubic meters of rock! Assuming a clean-cut, straight-sided cylinder with a height of 8 km and a diameter of 1 km, this is just over 6 billion cubic meters of empty space, about 5 times larger than the largest hole ever excavated on Earth.

If you want a cone shape, so that the colonists have some sunlight, you're looking at something on the order of a trillion (10¹²) cubic meters of removed rock. This is about a thousand times larger than the largest hole ever excavated on Earth. All of this removed material would mas about 3 quadrillion kg, 3x10¹⁵(Mars' crust is mostly basalt, which is roughly 3,000 kg/m³).

Call me cheap, but I wouldn't want to be the one that has to pay for the removal of 3 trillion tons of material on another planet.

 

[Baluncore]

What's your background? Biology?

All sciences.

I still think that the threat of decompression is much deadlier to deal with compared with the new conditions you mentioned though!

They will both kill you, does it really matter which is first?

Would the plants be able to transform the atmosphere within the crater to a more Oxygen rich one?

Yes, but only if it was sealed. You would need the right plants, and it would take a long time. You will need to employ tissue culture to set up a primitive carboniferous forest without flowering plants, insects, or fruit. Animals cannot tolerate high levels of CO₂. What will you eat while waiting? How will pollination be done?

The process of converting water and CO₂ into oxygen, will generate a huge mass of woody stems that you could use for structures. That material cannot be permitted to remain in the O₂ atmosphere because it will decay back to CO₂. On Earth, it was safe underground below the water table. We now call it fossil fuel.

 

[darkdave3000]

No. The oxygen will diffuse into the atmosphere and be spread throughout the planet.The Kola Borehole is only about a meter across! You're talking about moving something on the order of billions of cubic meters of rock! Assuming a clean-cut, straight-sided cylinder with a height of 8 km and a diameter of 1 km, this is just over 6 billion cubic meters of empty space, about 5 times larger than the largest hole ever excavated on Earth.

If you want a cone shape, so that the colonists have some sunlight, you're looking at something on the order of a trillion (10¹²) cubic meters of removed rock. This is about a thousand times larger than the largest hole ever excavated on Earth. All of this removed material would mas about 3 quadrillion kg, 3x10¹⁵(Mars' crust is mostly basalt, which is roughly 3,000 kg/m³).

Call me cheap, but I wouldn't want to be the one that has to pay for the removal of 3 trillion tons of material on another planet.

Did you miss the part about the 1 or 2 Hydrogen Bombs that could be involved? I never intended to suggest 1km diameter hole! Just enough to drop a Kzar Bomb or 2 clearing several square kms of higher air pressure(35,000 Pa) real estate!

 

[darkdave3000]

All sciences.They will both kill you, does it really matter which is first?Yes. But you would need the right plants, and it would take a long time. You will need to employ tissue culture to set up a primitive carboniferous forest without flowering plants, insects, or fruit. Animals cannot tolerate high levels of CO₂. What will you eat while waiting? How will pollination be done?

The process of converting water and CO₂ into oxygen, will generate a huge mass of woody stems that you could use for structures. That material cannot be permitted to remain in the O₂ atmosphere because it will decay back to CO₂. On Earth, it was safe underground below the water table. We now call it fossil fuel.

Yes it does matter which one kill u first, if a Bond villian ask Sean Connery if he wants to die by being thrown out an airlock into the vacuum of space or being thrown into a room with CO2 at 35,000 Pa I think Bond will choose the CO2 because he will die slower. Giving him enough time to cheat death with his laser wrist watch.

Btw, as for the second part, that doesnt sound like a bad situation to be in, those challenges are several orders of magnitude easier to deal with now with square kilometers of working space that does not threaten you with instant death.

Worst that could happen is a tear in your flimsy suit causing chocking instead of suffocation and you will have minutes to solve the problem instead of seconds.

Also now our green house domes can be thinner and made of less expensive plastic instead of glass. And we can fill the lakes with algae to speed up the conversion of the entire Martian atmosphere. That is if we keep extending the "river of life" by blasting or excavating with dozers sideways extending the canal continuously. We can actually make life possible within these canals without resorting to nuking the poles with hundreds of atom bombs as Elon suggests. Just 1 or 2 to start of with then the nuclear powered excavating machines take over, Mars is cold and 35,000 Pa is enough air pressure for the radiators to work on the excavators to keep the reactor cool. Yes the reactor will be liquid cooled in closed cycle.

I'm proposing creating some real estate that is substantially less lethal with higher survivability than the rest of Mars. Human Error type mistakes will be more forgiving down there giving you more time before those mistakes take your life.

This will increase comfort and confidence not to mention agility of humans to be able to study, craft and construct.

 

[Drakkith]

Did you miss the part about the 1 or 2 Hydrogen Bombs that could be involved? I never intended to suggest 1km diameter hole! Just enough to drop a Kzar Bomb.

If it's less than about 1 km in diameter, there really isn't enough room to do what you're suggesting, with lakes, and such. Besides, the numbers may go up or down, but they are proportionally similar. For even a small settlement you're looking at absurd amounts of rock that has to be moved, nukes involved or not.

Yes it does matter which one kill u first, if a Bond villian ask Sean Connery if he wants to die by being thrown out an airlock into the vacuum of space or being thrown into a room with CO2 at 35,000 Pa I think Bond will choose the CO2 because he will die slower. Giving him enough time to cheat death with his laser wrist watch.

Time of death is effectively identical in both scenarios. Unconsciousness in about 10 seconds, death within minutes.

Btw, as for the second part, that doesnt sound like a bad situation to be in, but those challenges are several orders of magnitude easier to deal with now with square kilometers of working space that does not threaten you with instant death.

Respectfully, I think you are asserting claims without any knowledge or expertise to back them up. There's little reason to think that working in a near-100% carbon dioxide atmosphere at STP conditions would be orders of magnitude easier than working in a near-vacuum. Both present unique challenges that don't have easy solutions.

 

[darkdave3000]

If it's less than about 1 km in diameter, there really isn't enough room to do what you're suggesting, with lakes, and such. Besides, the numbers may go up or down, but they are proportionally similar. For even a small settlement you're looking at absurd amounts of rock that has to be moved, nukes involved or not.Time of death is effectively identical in both scenarios. Unconsciousness in about 10 seconds, death within minutes.

Respectfully, I think you are asserting claims without any knowledge or expertise to back them up. There's little reason to think that working in a near-100% carbon dioxide atmosphere at STP conditions would be orders of magnitude easier than working in a near-vacuum. Both present unique challenges that don't have easy solutions.

I think you are now struggling to find ways to kill this idea!

Bond would have less of a struggle choking CO2 than suffocating in a vacuum, there's no contest here anyone reading this would agree! In a vacuum Bond would be like "I'm dead already!" , in a CO2 atmosphere he would be like "Oh crap pain pain, where is that wrist watch button, I better press it already!"

In fact he could just hold his breath! And keep his eyes closed, in a vacuum there's no right action!

Have you heard of a Tzar bomb? Do you have any idea how many megatons that yield is? The hole only needs to be a few meters in diameter to accomodate a Tzar bomb. Drop that in like Luke did to the Death Star and you got your billions of tons of earth out of the way.

 

[Drakkith]

I think you are now struggling to find ways to kill this idea!

Hah! No, just looking at some numbers is all. Numbers always take the fun out of everything, right?!

Bond would have less of a struggle choking CO2 than suffocating in a vacuum, there's no contest here anyone reading this would agree! In a vacuum Bond would be like "Im dead already!" , in a CO2 atmosphere he would be like "Oh crap pain pain, where is that wrist watch button, I better press it already!"

The issue is that both situations will leave you unconscious in about the same amount of time. They're both about equally deadly. Any differences between the two would likely only be a handful of seconds. The only real benefit to being shoved out into a CO2 atmosphere is that you can hold your breath. In a vacuum you cannot. The air pressure is simply too great.

Have you heard of a Kzar bomb? Do you have any idea how many megatons that yield is? The hole only needs to be a few meters in diameter to accomodate a Kzar bomb.

Perhaps, but I'm skeptical on how this will turn out. Eight kilometers is a LONG way down, and that's a LOT of rock to move, even for a big nuke.

 

[darkdave3000]

Hah! No, just looking at some numbers is all. Numbers always take the fun out of everything, right?!The issue is that both situations will leave you unconscious in about the same amount of time. They're both about equally deadly. Any differences between the two would likely only be a handful of seconds. The only real benefit to being shoved out into a CO2 atmosphere is that you can hold your breath. In a vacuum you cannot. The air pressure is simply too great.Perhaps, but I'm skeptical on how this will turn out. Eight kilometers is a LONG way down, and that's a LOT of rock to move, even for a big nuke.

I am grateful for your contributions to this thread with your knowledge on biology, it is not sufficient to kill this idea in my opinion but it does put a dent in my original vision. But I think your suggestion that vacuum and CO2 in a prssurized condition are equally lethal is laughable.

Yes both will eventually kill you but the question is which one gives you enough time and intact motor function and concousness to get out of that situation and alter fate? You can still remain conscious on the bottom of the crater with an oxygen tank even though the CO2 may be irritating you. But in a vacuum you will loose conciousness instantly.

Would you rather have a space suit rip on elevated areas of Mars or a rip in your flimsy stratospheric suit on the bottom of the Crater? A rip in a near vacuum wont give you much time for you to fix that rip. A rip in 35,000 Pa of CO2 will give you plenty of time to fix that rip, you can just grab it with your fist and walk home. Grabbing the same rip in a pressurized suit anywhere else on Mars wont be easy with high pressure spewing out due to preassure differential inside vs outside the suit. You will die before being able to walk back to a pressurized hab. See the difference is that in a pressurized environment there is no preassure difference inside and outside your suit preventing you from sealing that rip with your fist. Also you can still breathe oxygen in 35,000 pascal environment while you walk home holding that hole in your suit. Anywhere else and you cant even breath because the oxygen all rushes out!

It's sad that youve stopped being useful and resorted to being pedantic(and lack of in some other cases by ignoring certain things I'm saying such as using more than 1 nuke) in order to commit to your your original views on this idea instead of challenging your old views and being excited about the possibilities with this new idea.

Thanks for the useful bits! I'm grateful to know that CO2 atmosphere even pressurized will present it's own unique challenges. Thanks! Maybe I cant walk or swim naked on Mars out side of a plastic green house but it's possible I can walk around in a flimsy suit on it. Thats a lot more survivable than the other areas of Mars!

 

[Baluncore]

But I think your suggestion that vacuum and CO2 in a prssurized condition are equally lethal is laughable.

This appears to be a simple case of "ignorance is bliss".
https://en.wikipedia.org/wiki/Dunning–Kruger_effect

I think it would be easier, and much safer, to build the settlement on Earth, somewhere out in a desert.

 

[berkeman]

Thread closed for Moderation...

 

[berkeman]

After a Mentor review, this thread will remain closed. There is a bit too much handwaving by the OP for this to stand in the technical PF forums. Thank you to all who tried to help the OP.