totm sep 2024 terraforming mars... by digging.

[Nuke]

lots of crust. do a massive excavation several km deep. idea is simple. dig until the surface pressure and temperature is habitable. the bottom of valles marineris is close, about 7k down, and that is a good place to start. but we must go deeper. im not sure how far down you have to go. lets make our target 10 km, or 3km below the mariner valley. the fact that it goes east to west is convenient as it clears out sun blocking terrain by default.

i suppose the smart place to start is begin setting up road infrastructure. find a boring location to dump your dirt. if this location also has an ore processing capabilities to strip the soil of anything useful. especially any water ice it finds, metals, useful minerals.  might as well take scientific samples as well. the remains will need to be dumped somewhere (the south end looks boring and needs a big pile of dirt).  you want the road to be able to get down to the floor of the valley. so you put in switchbacks. these will be expanded and eventually you will need to widen the valley and reinforce the walls to support the 3km dig.

how do we do that. well really big excavators, dumptrucks, and bull dozers. the biggest we have. some examples are provided, but scale those up or bring a lot of them. they wont work on mars as is so you will need to retrofit them, with nuclear reactors. nuclear powered construction machinery, what could go wrong. i suppose you could spaceify a diesel to run on bi-propellant. but that depends on whether or not you built a methane plant yet. you might actually start with some smaller machinery, that you can use to start processing material, and then make the steel in situ to build the required bucket excavators and ore haulers. human crew is preferable as conducting what is effectively a dirt mining operation remotely would suck a lot.  good thing you have lots of dirt to bury the hab.

from here on out its a massive open pit mine 3 km deep. running your nuclear powered mars retrofit bagger 293 back and fourth from top to bottom on the northern and southern valley walls. several layers deep. to shallow the grade minimize the number of reinforcement piles you need to drive to prevent massive landslides. hopefully we have some kind of marscrete production going on. the dump yard would have a gravel processing operation going on by now. once the surface material is mostly removed, exposing bedrock, does mars have bedrock? idk. this actually simplifies things somewhat when you hit rock, convincing spacex to handle a shipment of high explosives will probibly not go down very well and would likely be the hard part. maybe you could find a local nitrogen source. you will also be able to start quarrying stone for future use.

ultimately what you are trying to build here is a bread basket. several kilometers of farmland that can be worked in shirt sleeves with just a breather unit. enough to feed a wider mars habitation. a number of large superconducting solenoids can be used to deflect all the nasty charged particles from space. meanwhile, at ye olde pile'o'dirt you can start removing the perchlorates from some of the more choice material. not anything from the first few layers, but the less radioactive stuff further down that got less space weather. manufacturing of live soil will either need to take place in a large pressurized surface structure, or in the pit. by this time, many decades in, there should be a lot of human waste and other organic wastes available. perfect mulch. maybe a starship full of earthworms. oh wait, co2. so either genetically engineered marsworms or put in some domes (hopefully by now reinforced marscrete is a thing) to maintain o2 in the structure. i dont think the atmosphere would ever be breathable unless you replace the co2 with nitrogen.

mars really is a dirt movers paradise. and industrializing a dead world that shows no signs of reanimating itself sounds a lot better than replacing all the trees with holograms of trees.

[Gargamel]

I like the valley idea, but I don’t think it’s necessary.     
 

First off, the machinery would have to be made in situ as you say.     As someone who makes such machinery, I can tell you that a single gear from these machines can weigh in excess of 700kg each.   It just wouldn’t be practical to launch one of these dump trucks in that manny launches.   And they’d have to be designed from the ground up, by a consortium of engineers from multiple disciplines, basing a design around earth bound equipment probably wouldn’t be suitable for mars.  
 

Secondly, I don’t think big diggers and earth movers are the way to go.    Too many individual machines, too many people.   We’d probably be best looking at a surface adaptation of a Long Wall System.   https://en.m.wikipedia.org/wiki/Longwall_mining
Adapat the design to be surface run, have it take a 5m slice off the face, run that down 10km or so, take a step forward, repeat.    All the rubble gets removed via long conveyor.   This whole thing could run off a single nuclear reactor instead of the dozens that dump truck system would entail.   Not sure how wide the valley is, might need to make a few passes or add a couple walls to make it work.   This would reduced personnel significantly and increased uptime of the system.   
 

But do we really need to dig?    We’re going to need a “dome” anyways, so why not just construct one using the walls of the valley and build the city in there?    It’ll get most of the elevation drop you want.   

[darthgently]

If energy and lighting tech get efficient enough then entire underground caverns could be terra formed with virtually natural daylight lighting with trees, farms, etc.   Might be a good alternative to attempting to fully convert the surface.  It would be a real bummer to create a real breathable atmosphere topside only to watch it get stripped away at a higher than acceptable rate

Edited August 14 by darthgently

[darthgently]

11 minutes ago, Gargamel said:

 

But do we really need to dig?    We’re going to need a “dome” anyways, so why not just construct one using the walls of the valley and build the city in there?    It’ll get most of the elevation drop you want.

The thing with domes on Mars is that the meteor impacts are still relatively frequent.  Same on Moon.  I could see observation domes as recreational areas but in the short term I figured underground makes most sense for radiation and terraforming purposes.  For the critical facilities for sure.  Especially given the depths the new water indications point at.  The deeper, the warmer and wetter with better rad and impact protection.  Get a stable economy going underground then push onto the surface as resources and technological advancement allow.  

The longwall mining does look well suited for big digs on Mars for the reasons you spell out

[farmerben]

Pavonis Mons is an ideal spot for an agricultural city as well as other things.  There is a deep crater to dome over and hold atmosphere.  Natural rock will provide radiation shielding for all but a slice of sky.  The center of the dome/crater could become agricultural while the habitations are carved into the walls of the crater.  The other nice thing about Pavonis Mons is the rim is right on the equator so it an ideal spaceport, or a rail launched mass driver.  All the spoil from excavating can be rolled down the slopes of the mountain to create tracks for mass driver/rail/road/electricity transport.  The top of the mountain is above the height of many dust storms so cleaning the solar panels is relatively easier than at low elevation.  Not sure about water.  Water and air might have to be hauled in and continuously recycled.  It makes more sense to grow your veggies in containers for water recycling and other reasons.  Giant dehumidifiers will be needed to catch the moisture from plants and animals.  The basic floor and walls of the crater can be left as bare rock.  That is somewhat permeable to air and water.  But allows you to be constantly working fresh ground.

https://en.wikipedia.org/wiki/Pavonis_Mons

Edited August 14 by farmerben

[Gargamel]

2 hours ago, darthgently said:

he longwall mining does look well suited for big digs on Mars for the reasons you spell out

Yeah, the more I think about it, the more practical this seems.   
 

Not only will the digging capacity be at least comparable to a bagger system, relatively speaking, but the baggers are the largest land vehicles ever made by man.   On earth, with the entirety of modern industrial society available to help.   Building anything similar on Mars, in Situ or not, is a completely ridiculous notion.     Not saying a big digger is a bad idea, just anything _that_ big.    
But the Long Wall will give you similar constant capacity, the infrastructure would be identical in some areas (The long conveyor) , and a couple orders of magnitude less in others (the actual cutter head).  
 Plus the long wall can be setup to do bedrock while a bagger can only do loose material.   

Edited August 14 by Gargamel
Whoopsie, typo’d a bad word.

[Nuke]

1 hour ago, Gargamel said:

I like the valley idea, but I don’t think it’s necessary.     
 

First off, the machinery would have to be made in situ as you say.     As someone who makes such machinery, I can tell you that a single gear from these machines can weigh in excess of 700kg each.   It just wouldn’t be practical to launch one of these dump trucks in that manny launches.   And they’d have to be designed from the ground up, by a consortium of engineers from multiple disciplines, basing a design around earth bound equipment probably wouldn’t be suitable for mars.  
 

Secondly, I don’t think big diggers and earth movers are the way to go.    Too many individual machines, too many people.   We’d probably be best looking at a surface adaptation of a Long Wall System.   https://en.m.wikipedia.org/wiki/Longwall_mining
Adapat the design to be surface run, have it take a 5m slice off the face, run that down 10km or so, take a step forward, repeat.    All the rubble gets removed via long conveyor.   This whole thing could run off a single nuclear reactor instead of the dozens that dump truck system would entail.   Not sure how wide the valley is, might need to make a few passes or add a couple walls to make it work.   This would reduced personnel significantly and increased uptime of the system.   
 

But do we really need to dig?    We’re going to need a “dome” anyways, so why not just construct one using the walls of the valley and build the city in there?    It’ll get most of the elevation drop you want.   

you might have silo type habs that are domed over for agricultural use for that colony. this ultimately caps its population, some fraction of which tends to crops and hab maintenance. you thus reduce the number you have for additional construction, mining and science activities. having a large bread basket region can allow for more specialized colonies. of course a low sunken dome has other benefits, like not having to deal with a pressure difference. it might be less of a dome and more of a frame for mylar panels, ultimately an oxygen catch. the low position allows piping of water from ice fields.

[kerbiloid]

https://www.grc.nasa.gov/www/k-12/airplane/atmosmrm.html

p = .699 * exp(-0.00009 * h,m) , kPa

(ln(100/.699)/0.00009)/1000 ~= 55 km depth. Probably needs an asteroid hit.

Presuming that the Martian rocks are same dense and strong as the terrestrial ones, the maximum vertical gradient (highest peak, deepest pit) is 25..30 km (Earth's 10..12 km / Mars's 0.4 g).

pressure ~= .699 * exp(-0.00009 * 30 000) / 100 ~=0.05 atm (like at 25 km above the Earth).

***

And as the Science News tell, there is probably a wet-gravel water ocean at ~20 km depth.

So, the 30 km trench would be flooded.

***

9 hours ago, Nuke said:

the biggest we have. some examples are provided

GMO earthworms rule.

Spoiler

[Spacescifi]

15 hours ago, Nuke said:

lots of crust. do a massive excavation several km deep. idea is simple. dig until the surface pressure and temperature is habitable. the bottom of valles marineris is close, about 7k down, and that is a good place to start. but we must go deeper. im not sure how far down you have to go. lets make our target 10 km, or 3km below the mariner valley. the fact that it goes east to west is convenient as it clears out sun blocking terrain by default.

i suppose the smart place to start is begin setting up road infrastructure. find a boring location to dump your dirt. if this location also has an ore processing capabilities to strip the soil of anything useful. especially any water ice it finds, metals, useful minerals.  might as well take scientific samples as well. the remains will need to be dumped somewhere (the south end looks boring and needs a big pile of dirt).  you want the road to be able to get down to the floor of the valley. so you put in switchbacks. these will be expanded and eventually you will need to widen the valley and reinforce the walls to support the 3km dig.

how do we do that. well really big excavators, dumptrucks, and bull dozers. the biggest we have. some examples are provided, but scale those up or bring a lot of them. they wont work on mars as is so you will need to retrofit them, with nuclear reactors. nuclear powered construction machinery, what could go wrong. i suppose you could spaceify a diesel to run on bi-propellant. but that depends on whether or not you built a methane plant yet. you might actually start with some smaller machinery, that you can use to start processing material, and then make the steel in situ to build the required bucket excavators and ore haulers. human crew is preferable as conducting what is effectively a dirt mining operation remotely would suck a lot.  good thing you have lots of dirt to bury the hab.

from here on out its a massive open pit mine 3 km deep. running your nuclear powered mars retrofit bagger 293 back and fourth from top to bottom on the northern and southern valley walls. several layers deep. to shallow the grade minimize the number of reinforcement piles you need to drive to prevent massive landslides. hopefully we have some kind of marscrete production going on. the dump yard would have a gravel processing operation going on by now. once the surface material is mostly removed, exposing bedrock, does mars have bedrock? idk. this actually simplifies things somewhat when you hit rock, convincing spacex to handle a shipment of high explosives will probibly not go down very well and would likely be the hard part. maybe you could find a local nitrogen source. you will also be able to start quarrying stone for future use.

ultimately what you are trying to build here is a bread basket. several kilometers of farmland that can be worked in shirt sleeves with just a breather unit. enough to feed a wider mars habitation. a number of large superconducting solenoids can be used to deflect all the nasty charged particles from space. meanwhile, at ye olde pile'o'dirt you can start removing the perchlorates from some of the more choice material. not anything from the first few layers, but the less radioactive stuff further down that got less space weather. manufacturing of live soil will either need to take place in a large pressurized surface structure, or in the pit. by this time, many decades in, there should be a lot of human waste and other organic wastes available. perfect mulch. maybe a starship full of earthworms. oh wait, co2. so either genetically engineered marsworms or put in some domes (hopefully by now reinforced marscrete is a thing) to maintain o2 in the structure. i dont think the atmosphere would ever be breathable unless you replace the co2 with nitrogen.

mars really is a dirt movers paradise. and industrializing a dead world that shows no signs of reanimating itself sounds a lot better than replacing all the trees with holograms of trees.

 

You've seen the news about oceans on Mars have'nt you?

Living like mole rats will save humans from radiation exposure, but building the infrastructure would be time consuming, expensive, and risky.

Edited August 14 by Spacescifi

[Nuke]

9 hours ago, kerbiloid said:

https://www.grc.nasa.gov/www/k-12/airplane/atmosmrm.html

p = .699 * exp(-0.00009 * h,m) , kPa

(ln(100/.699)/0.00009)/1000 ~= 55 km depth. Probably needs an asteroid hit.

Presuming that the Martian rocks are same dense and strong as the terrestrial ones, the maximum vertical gradient (highest peak, deepest pit) is 25..30 km (Earth's 10..12 km / Mars's 0.4 g).

pressure ~= .699 * exp(-0.00009 * 30 000) / 100 ~=0.05 atm (like at 25 km above the Earth).

***

And as the Science News tell, there is probably a wet-gravel water ocean at ~20 km depth.

So, the 30 km trench would be flooded.

***

GMO earthworms rule.

  Reveal hidden contents

the important thing is the bottom of the hole is wet.

[kerbiloid]

3 hours ago, Nuke said:

the important thing is the bottom of the hole is wet.

Allows to drown the sandtrouts for spice.

[farmerben]

For a mission we could do today.  Land a stationary probe in the center of the caldera on Pavonis Mons.  Equip it with high quality telescopic cameras and radar.  You can scan the entire vertical surface looking for caves, and scanning the minerals as best you can from 20 km away.  

The cliff walls of the caldera are over 150 km in circumference and 5 km high.  Dust does not rest on vertical surfaces.

[Nightside]

Radiation is a concern for even shallow basements on earth. Would Radon, etc be a major concern for deep excavations on Mars?

[kerbiloid]

9 hours ago, Nightside said:

Would Radon, etc be a major concern for deep excavations on Mars?

If the Mars is rich of heavy radioactive elements, producing the radon.

[farmerben]

It's not on my list of major concerns period.  You could more than make up for the dose by eating less radioactive potassium, fewer fresh outdoor grown fruits and so on.

[Terwin]

19 hours ago, Nightside said:

Radiation is a concern for even shallow basements on earth. Would Radon, etc be a major concern for deep excavations on Mars?

If you have uranium, thorium or radium under you, then Radon will bubble up.

If you have an air-tight seal both top and bottom, then the radon will just go around.

Radon is a heavy gas that will settle in low areas once there is no longer denser stuff pressing down on it.  Basements are a great place for collecting Radon if you have it in the area.

An air-tight base will not be able to collect radon the same way, because it will not have a nice sheltered basin to collect in.

Also, mars is much smaller and lighter than earth, does it even have the same prevalence of heavy/radioactive elements as earth?

Didn't the moon take a big chunk of lighter materials away from earth, making it denser than average for a rocky body?

It might turn out that finding places where Radon vents on mars could be very exciting from a prospecting for radioactives front.

[kerbiloid]

And avoid any building on top of an even small geological fault. They are radon fountains. I know, I was a local measurer.

[Kimera Industries]

There was an alien relic based on this idea in the book The Long Mars, by Terry Pratchett and Stephen Baxter. 

[Nuke]

made totm. cool.

[magnemoe]

On 8/19/2024 at 5:44 PM, Terwin said:

If you have uranium, thorium or radium under you, then Radon will bubble up.

If you have an air-tight seal both top and bottom, then the radon will just go around.

Radon is a heavy gas that will settle in low areas once there is no longer denser stuff pressing down on it.  Basements are a great place for collecting Radon if you have it in the area.

An air-tight base will not be able to collect radon the same way, because it will not have a nice sheltered basin to collect in.

Also, mars is much smaller and lighter than earth, does it even have the same prevalence of heavy/radioactive elements as earth?

Didn't the moon take a big chunk of lighter materials away from earth, making it denser than average for a rocky body?

It might turn out that finding places where Radon vents on mars could be very exciting from a prospecting for radioactives front.

Yes, basements are rarely water thigh.  Idea is tempting, but for normal houses an flood would make the house float up or basement floor will break unless you build it of reinforced concrete who they do on city blocks who tend to be concrete anyway.