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People sometimes forget that steel is not the only way of reinforcing concrete:
https://www.deutsche-basalt-faser.de/en … forcement/
"Basalt Rebar is an outstanding product for concrete reinforcement. It weighs 4 times less than steel rebar and its tensile strength is 3 times higher. Basalt rebars are manufactured from basalt fibers by pultrusion technology. The surface is profiled and sanded. This kind of surface treatment results in a better adhesion in concrete."
This seems like an obvious way to go on Mars - use the plentiful basalt to reinforce the concrete. Finding goods sources of calcium carbonate is going to be a lot more difficult.
Building buildings on Mars is very, very different from building buildings on Earth. Precisely because Martian buildings must be strongly pressurized to be habitable, and Earthly buildings are entirely free of this requirement. Pressurization means your structures must resist high tension and/or high bending. Bending involves high tension, too.
Our masonry materials (cemented bricks and stones, concrete) have good compressive strength, but lousy to vanishing tensile strength. The partial (PARTIAL !!!) exception is reinforced concrete. The steel rebar in reinforced concrete carries the tensile loads, but ONLY because the Young's Modulus of steel is much higher than the Young's Modulus of the concrete matrix. That means you cannot use other materials of lower modulus than steel as your substitute rebar.
You can load the rebar to the point where the concrete cracks, but no further. Once cracked, the concrete's compressive strength degrades, sometimes is lost completely. On Mars, if you lose building pressurization, the compressive strength is required to prevent collapse under its own weight, lower gravity notwithstanding. Lose compressive strength because you cracked the concrete matrix, and the building falls. The rebar WILL NOT prevent that.
These concrete and cement structures really are porous. They will not be airtight without an appropriate coating on the inside. If you crack them, you tear that coating. Just something else to consider.
Also, consider the cold soak temperature effects we see on Mars that we don't even see at South Pole Station (coldest ever seen ~-115 F = ~ -82 C). Mars has -130 F or colder, quite commonly. It can get to -200 F in some places. I don't know what effect that might have on the concrete matrix, or other masonry, but it is catastrophic on the usual mild carbon steel we use for rebar. It becomes as brittle and fragile as a glass window pane.
Your rebar will have to be 304 stainless, 304L if you intend to weld it (and most rebar is welded). That is a high-nickel steel that does not heat treat, although it cold-works very hard very quickly. It is NOT magnetic, so that means of material handling gets ruled out.
Just more food for thought.
Bear in mind that these masonry and concrete materials (and the related soil mechanics for foundations) were not the focus of my aerospace education, nor of the strength of materials classes that I had in college as an aerospace student. I learned most of this on the job working in one or another aspect of civil engineering.
GW
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Thanks Louis and kbd512 for posting with a headline/source!
For the others: If you want your post to be noticed in the future, please add a caption as well.
Thanks Thomas for mentioning the important posts.
Sorry I didn't reply to all the comments, I'm working busy on the concept right now. But I have read all your comments and picked out some interesting stuff.
Last edited by Noah (2021-04-17 22:55:51)
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CV/ learning status
Thomas asked me to give a brief CV/ learning status, so here it goes:
School
After elementary school I went to a high school ( "Marie-Curie-Gymnasium" in Germany).
Internships
During high school, I did internships during the vacations, in 10th and 11th grade. The internships were with a well-known architectural firm called RKW +. There I designed a building from scratch and went through the whole design process, which is similar to the settlement design process.
Architecture competition
After the internships, I participated in an architecture competition for students, where we
were to design and draw a skyscraper. I won a “Sonderpreis” (special prize).
Study
Shortly after graduating from high school, I took an entrance test for ETH Zurich.
Now I study physics at ETH Zurich and design a settlement desgin with all of you
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General Mission Architecture
This thread is Exhibit A as to why we've never left Earth to explore and colonize the moon or Mars. Instead of admitting to technological reality and selecting existing or technologically feasible equipment that's flight-qualified and thoroughly tested, every attempt to do a worthwhile mission devolves into a pointless ideology battle with various dogmatic, ideologically-motivated special interest groups who do everything in their power to derail productive strategies and technologies selected to achieve the stated program objectives for minimum cost, weight, and power consumption, in favor of some undefined or impractical futuristic technology that doesn't physically exist. They'd much rather prevent a mission from happening in the first place than they would see anything other than their pet project or technology used in another meaningless crusade to prop up their ideology. Now you know why we still haven't been to Mars decades after we had the basic requisite technology to go there and come back, with a reasonably good chance of returning a crew alive and in good physical condition. It was never a matter of technological readiness, but a matter of development priorities and ideology over engineering. Unfortunately, ideology can't make a round peg fit in a square hole, not that that will ever stop the ideologues from trying.
Yes, I think you're right and it's good to keep that in mind during the design process.
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Louis
I've taken a fairly detailed look at the ECLSS document.
https://www.mars-one.com/images/uploads … ssment.pdf
While it's very thorough, I'm not sure how it relates to a city of one million.
Looks interesting thanks!
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Discussion
I will periodically post a topic (from post #1) I am working on or will be working on and if you have any advice or useful information, feel free to post a comment.
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My concept of the NewMars version of a Wiki...
A bit of a caution. Robert Zubrin is an amazing leader, founded the Mars Society and continues as president. I have met him at Mars Society conventions, and we've worked together enough that he has gotten to know me. However, everyone is human. Let me tell you a little story.
I joined the Mars Society in 1999. I had purchased "The Case for Mars" in spring of 1998, and it described "The Case for Mars" conventions every 3rd year, the next was later that same year. But I couldn't afford to go. That convention was the founding convention for the Mars Society; if I went, I could have called myself a founding member. In 1999 there was the first forum, before this one. Members were excited, the society got a lot of donations from individuals who got rich from the internet bubble. The purpose of the society said: "Starting small, with hitchhiker payloads on government funded missions, we intend to use the credibility that such activity will engender to mobilize larger resources that will enable stand-alone private robotic missions and ultimately human exploration." It's changed now, but that's what it was. This was seen by members as a goal to send a Society mission to Mars, hitchhiking on a "government" mission. Deep Space One was in space at the time, so I asked why don't we send something small now? As a hitchhiker payload on NASA Space Shuttle. Members debated what the mission should be. That first forum didn't have a feature to vote, so I wrote code and hosted it on a work server to let members vote. The majority voted for a balloon. Ok, so let's get serious. Can we design a balloon mission for Mars?
Members from the Spain chapter wanted to build and pay for the balloon itself. I suggested we use Robert Zubrin's design for a balloon. He got a contract from JPL to build a proof-of-concept balloon. His idea was to prefill with methanol, store the balloon in a hard clam-shell. The balloon would be deployed while hanging on a parachute. Aeroshell to enter Mars atmosphere, then when it slows to sufficiently open a drogue 'chute, then a main parachute. While dangling on the parachute, deploy the balloon. The balloon would be coloured black, so during the day sunlight would warm the balloon, causing it to expand and ascend. At night it would get cold, descend. A heavy rope dangling would strike the ground first, as weight is taken by the ground, the balloon would stop descending. This allowed a soft landing. The test funded by JPL used a stratospheric balloon to take it to air that has the same pressure and temperature as Mars atmosphere, then deploy the Mars balloon there under the stratosphere balloon. It worked. Ok, so let's do that. I asked interested members what their skill and job or certification was. An electrical engineer who specialized in building power supplies for Cisco equipment wanted to design/build the power supply for our mission. Another member worked for a military contractor who had bid to supply the propellant tank for the multiple warhead bus for Minuteman missiles. They didn't get the contract, but the idea was interesting: a titanium tank that would collapse like a cinnamon roll as propellant drained, providing constant pressure. He wanted his employer to provide the tank for our mission. At the time my job was Senior QNX Analyst, developing software for the QNX operating system. The company that developed/sold QNX bragged that the vision system for CanadArm2 on ISS used QNX. It's a high reliability version of Unix developed in Canada. VxWorks is a high reliability version of Unix developed in USA, used for Mars rovers; a competitor of QNX. So I said that I would write the software. I found a company in California that built commercial-off-the-shelf space hardened electronics: computers, memory, etc. Another member just finished his Ph.D. in aerospace engineering in Australia, specializing in aeroshells. He asked to provide the aeroshell for our mission. Wow! Of course I said yes. That engineer Paul Wooster, he's now Principal Mars Development Engineer at SpaceX.
Turned out there was 3 other groups within the Mars Society who wanted to build a balloon; one was the Spain chapter. I got them all to work together.
I called NASA/Glenn Research Centre to ask what information I could get about the NSTAR ion engine used for Deep Space One. They had the lead engineer who developed NSTAR call me back. He sent me everything that was allowed outside USA. As he put it, everything short of the blueprints. I called the Small Shuttle Payloads Project. The Director himself answered my call. I asked how much for a Get-Away Special. He said it was $8,000 for a US educational institution, or $27,000 for anyone else. But the catch is it had to go up and come down. If something deployed out of the Shuttle payload bay, then it was $2 million, and that's called a Hitchhiker mission. He apologized profusely, said it wasn't his idea, that NASA executives didn't want to compete with commercial launchers. But he then said that with my connections, I should be able to get a NASA agency (as he put it) to sponsor our mission. With that we would get a free ride to space. And he gave me the form number that we would have to fill out.
So I went to Robert Zubrin to ask to make this an official Mars Society project. After all, we would need someone at a NASA cost centre to sponsor us. A few NASA employees were members of the Board of Directors. Dr Zubrin said no. He said not everyone on our team were professional engineers. Uh... the whole point was to send an official Mars Society mission to Mars. For real. The Mars Society was supposed to be about enabling average citizens to work together with professional scientists and engineers: NASA, CSA, ESA, etc. So... uh... what?
Without it being an official project, I stopped working on it. Without me, the project died. I had become the de facto project head.
After our project died, the German chapter started a balloon project. They restricted it to professional aerospace engineers. It hasn't happened.
Of course after the Columbia accident, NASA said no small explorers on Shuttle. So we lost our ride to space. And now Shuttle doesn't fly at all.
In "The Case for Mars" Robert Zubrin wrote that Mars would allow anyone who could do work to do so. Not restrict you by certification. However, when it comes down to it, he is focused on academic qualifications. I thought we had a Wiki on NewMars at one point. But not now. James Burk is webmaster for the main Mars Society website, and works with Dr Zubrin. He's one of the administrators for NewMars. Not surprising that the Wiki is now just for those with qualifications.
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Interesting story Robert! I didn't know you joined the Mars Society so early. Great that you are still active after 22 years!
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For Noah re recent updates and your CV! .... Thanks for keeping the conversation in focus.
I do have one question about your preference for 8 people in a mission ... You no doubt saw the recommendation of 17 by Oldfart1939.
If you have time, please analyze the options for various size teams, and how the number 8 won out in the end. Someone, somewhere, ** had ** to make decisions, and having made this one, you are free to concentrate on requirements for that number.
There are some who worry that the number is too small for success on a two (Earth) year minimum mission (as you will have noted in arriving at your decision).
The number of people on site can be supplemented by teams back on Earth, and the smaller the group on site, the greater the needed for companions back on Earth who are closely tied to the onsite members on an individual basis.
(th)
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For RobertDyck re #208
Thanks for the caution regarding the environment within which the NewMars forum is privileged to have a (small) place.
I appreciate the analysis of the possible reaction to a Wiki designed for the NewMars forum.
I woke up early with a variety of thoughts/insights/doubts swirling around this concept, and was pleased to find your historical presentation.
A Wiki may NOT be the best structure for what I think is needed, and certainly NOT a Wiki that is controlled by a someone who is trying to maintain an agenda.
What we ** have ** now is a hodge podge of posts of every possible kind, of every possible size, covering (just about) any possible subject.
We have a great deal of duplication of effort, both by single individuals and by sets of individuals working the same ground independently.
For Noah ....
Please be thinking about what kind of structure for information might help you and your team going forward.
If NewMars can adapt itself to your needs, then there will be no need for you to go elsewhere.
Here are some notes I jotted down earlier today:
Location ... at Meta Index level? (rather than Mars Society)
NewMars Repository (not necessarily a Wiki but perhaps structured with some similarity)
Categories ...
Alternate Futures (Louis is a specialist in this arena, along with Void)
Speculative Alternate Futures (Void is the unequalled master of this domain)
Projects ... there are too many for me to list (or even remember) ...
RobertDyck
Calliban
kbd512
SpaceNut
Practical Advice
GW Johnson is the master of this domain, with plenty of assistance from:
kbd512, SpaceNut, Oldfart1939, Calliban and others (reminders of names welcome) (many are in the archive)
Careers
Generally My Hacienda territory
Specializations
Definitely My Hacienda territory
Businesses
Overlap with My Hacienda
Expeditions
A category hinted at in many posts, but never given much substance
****
Note ... we have new members since the Great Spammer Lockout
We will accomplish nothing if we admit new members and they disappear.
I'm starting to think about requesting a monthly update from members admitted since the Great Spammer Lockout
Marc is working on his PhD and developing a minicomputer that ** could ** be perfect for Mars
He might be willing to provide a short summary of progress on a monthly basis ... I'll ask him
Captain J Torriani is a student in Mexico. If he is concentrating on his education, that is all to the good, and I trust that the members of this forum will applaud his progress. I'll write to inquire if he too might be willing to provide a monthly update on his studies.
Noah is participating beyond my hopes!
First of all, he came up with a topic that is well received by the membership, and generously supported.
He took his time (as I recall several weeks) and then opened the new topic with a polished look that he is continuing to enhance.
Post 1 is ** not ** static! SpaceNut showed Noah how to enhance Post #1, and Noah has been doing so ever since.
We don't need a monthly report from Noah. On the ** other ** hand, a monthly report would be helpful in two ways ...
It would give Noah an opportunity to assess progress toward developing a detailed plan for an expedition (if that is where he is headed)
It would give the membership some feedback on how we (group) are doing in supporting his vision (whatever it is at a point in time)
(th)
Online
I was amazed to find out a few years ago that The Case for Mars was out of print. Actually I was quite shocked. Given Musk and Space X are so much in the news you would think there would be an audience for a book on Mars colonisation.
Space X clearly still see value in the Mars Society, but it is rather sad the way Zubrin seems unable to accept that the Space X approach is totally different from the Mars Direct mission architecture.
I'm sorry you didn't get to take your project further, Robert. The balloon mission would have been very interesting 20 years ago.
I think it is a mistake for the scientifically edcuated to shut themselves off from the rest of humanity.
Besides with Google these days, even those without a scientific background can do some basic research - like I did just before about concrete reinforced with basalt rebar rather than steel rebar.
One of Musk's strengths is that he is a kind of engineer (don't think he ever completed his studies IIRC) but not too much. He hasn't had creativity educated out of him and he is connected to the wider culture about him.
tahanson43206 wrote:My concept of the NewMars version of a Wiki...
A bit of a caution. Robert Zubrin is an amazing leader, founded the Mars Society and continues as president. I have met him at Mars Society conventions, and we've worked together enough that he has gotten to know me. However, everyone is human. Let me tell you a little story.
I joined the Mars Society in 1999. I had purchased "The Case for Mars" in spring of 1998, and it described "The Case for Mars" conventions every 3rd year, the next was later that same year. But I couldn't afford to go. That convention was the founding convention for the Mars Society; if I went, I could have called myself a founding member. In 1999 there was the first forum, before this one. Members were excited, the society got a lot of donations from individuals who got rich from the internet bubble. The purpose of the society said: "Starting small, with hitchhiker payloads on government funded missions, we intend to use the credibility that such activity will engender to mobilize larger resources that will enable stand-alone private robotic missions and ultimately human exploration." It's changed now, but that's what it was. This was seen by members as a goal to send a Society mission to Mars, hitchhiking on a "government" mission. Deep Space One was in space at the time, so I asked why don't we send something small now? As a hitchhiker payload on NASA Space Shuttle. Members debated what the mission should be. That first forum didn't have a feature to vote, so I wrote code and hosted it on a work server to let members vote. The majority voted for a balloon. Ok, so let's get serious. Can we design a balloon mission for Mars?
Members from the Spain chapter wanted to build and pay for the balloon itself. I suggested we use Robert Zubrin's design for a balloon. He got a contract from JPL to build a proof-of-concept balloon. His idea was to prefill with methanol, store the balloon in a hard clam-shell. The balloon would be deployed while hanging on a parachute. Aeroshell to enter Mars atmosphere, then when it slows to sufficiently open a drogue 'chute, then a main parachute. While dangling on the parachute, deploy the balloon. The balloon would be coloured black, so during the day sunlight would warm the balloon, causing it to expand and ascend. At night it would get cold, descend. A heavy rope dangling would strike the ground first, as weight is taken by the ground, the balloon would stop descending. This allowed a soft landing. The test funded by JPL used a stratospheric balloon to take it to air that has the same pressure and temperature as Mars atmosphere, then deploy the Mars balloon there under the stratosphere balloon. It worked. Ok, so let's do that. I asked interested members what their skill and job or certification was. An electrical engineer who specialized in building power supplies for Cisco equipment wanted to design/build the power supply for our mission. Another member worked for a military contractor who had bid to supply the propellant tank for the multiple warhead bus for Minuteman missiles. They didn't get the contract, but the idea was interesting: a titanium tank that would collapse like a cinnamon roll as propellant drained, providing constant pressure. He wanted his employer to provide the tank for our mission. At the time my job was Senior QNX Analyst, developing software for the QNX operating system. The company that developed/sold QNX bragged that the vision system for CanadArm2 on ISS used QNX. It's a high reliability version of Unix developed in Canada. VxWorks is a high reliability version of Unix developed in USA, used for Mars rovers; a competitor of QNX. So I said that I would write the software. I found a company in California that built commercial-off-the-shelf space hardened electronics: computers, memory, etc. Another member just finished his Ph.D. in aerospace engineering in Australia, specializing in aeroshells. He asked to provide the aeroshell for our mission. Wow! Of course I said yes. That engineer Paul Wooster, he's now Principal Mars Development Engineer at SpaceX.
Turned out there was 3 other groups within the Mars Society who wanted to build a balloon; one was the Spain chapter. I got them all to work together.
I called NASA/Glenn Research Centre to ask what information I could get about the NSTAR ion engine used for Deep Space One. They had the lead engineer who developed NSTAR call me back. He sent me everything that was allowed outside USA. As he put it, everything short of the blueprints. I called the Small Shuttle Payloads Project. The Director himself answered my call. I asked how much for a Get-Away Special. He said it was $8,000 for a US educational institution, or $27,000 for anyone else. But the catch is it had to go up and come down. If something deployed out of the Shuttle payload bay, then it was $2 million, and that's called a Hitchhiker mission. He apologized profusely, said it wasn't his idea, that NASA executives didn't want to compete with commercial launchers. But he then said that with my connections, I should be able to get a NASA agency (as he put it) to sponsor our mission. With that we would get a free ride to space. And he gave me the form number that we would have to fill out.
So I went to Robert Zubrin to ask to make this an official Mars Society project. After all, we would need someone at a NASA cost centre to sponsor us. A few NASA employees were members of the Board of Directors. Dr Zubrin said no. He said not everyone on our team were professional engineers. Uh... the whole point was to send an official Mars Society mission to Mars. For real. The Mars Society was supposed to be about enabling average citizens to work together with professional scientists and engineers: NASA, CSA, ESA, etc. So... uh... what?
Without it being an official project, I stopped working on it. Without me, the project died. I had become the de facto project head.
After our project died, the German chapter started a balloon project. They restricted it to professional aerospace engineers. It hasn't happened.
Of course after the Columbia accident, NASA said no small explorers on Shuttle. So we lost our ride to space. And now Shuttle doesn't fly at all.
In "The Case for Mars" Robert Zubrin wrote that Mars would allow anyone who could do work to do so. Not restrict you by certification. However, when it comes down to it, he is focused on academic qualifications. I thought we had a Wiki on NewMars at one point. But not now. James Burk is webmaster for the main Mars Society website, and works with Dr Zubrin. He's one of the administrators for NewMars. Not surprising that the Wiki is now just for those with qualifications.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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It sounds like Zubrin is risk averse and was worried about the prject not working and damaging the Mars Society reputation. He also sounds a little possessive; like all of us he has an ego. None the less, from what Robert describes, the balloon mission must be considered a lost opportunity. The same with the wiki. There is little danger in allowing non-engineers to produce useful articles, as there are engineers available to guide them on technical facts. And the site owner can always withdraw articles that don't stand up to peer review, so I don't really understand the problem.
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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Noah's reminder;
The crew size is determined when the amount of mass from each incremental person slows the amount of change in ship dry mass to get man leaving Earth to go to mars as to the only thing changing are the life support quantities.
Which effects recycling numbers.
What goes into the selection process
https://www.mars-one.com/mission/mars-one-astronauts
Some of the risk
https://ieeexplore.ieee.org/document/6836241
Nasa Gateway mission to Phobos is a prover that we can survive
https://www.space.com/29562-nasa-manned … hobos.html
The Cost and Equivalent System Mass of Space Crew Time
https://spacecraft.ssl.umd.edu/design_l … e_cost.pdf
This is the one that talks to all of how the rockets are designed all the way to its surface and back to earth for the crews survival which means it covers the ballistic entry to mars
Part 1 & 2
https://space.nss.org/wp-content/upload … o-Mars.pdf
The only thing effecting growth on mars is health issues to crew under reduced gravity, extended stays for growth of population for mars. This is where we learn from the ISS for type of medical monitoring, exercise program and mediation counter action effects program. In investigation of spin tables for increased AG needs to be done as well as weighted arm, wrist, ankle plus clothing as counter measures.
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Louis-
Musk has an undergraduate degree in Physics, and a second one in Business. A self educated engineer with good math skills.
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For Oldfart1939 re #215
Thanks for the reminder of Mr. Musk's educational background.
I would add to your summary [self educated engineer with good math skills] that Mr. Musk has social skills of a very high order, in addition to the ability to judge character of prospective helpers. Somewhere in the mix is an extraordinary combination of willingness to take calculated risks, and good judgement.
(th)
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The adaptation of living here underground with a mars twists seems possible
Cappadocia: Inside Turkey's incredible underground city
Spanning 18 floors to a depth of 85 meters, Derinkuyu is one of the largest and deepest subterranean cities in Turkey.
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I think that's an excellent inspiration for a Mars City, SpaceNut.
I could see a variation on that theme where it is more of a canyon effect with living and work space tunnelled into the sides.
Illumination would be an issue. A glass roof at the top of the canyon would be possible. We could reflect light on to that strip of glass roof to boost illumination. I would like to use lightwells (lightpipes) but am concerned whether pressurisation issues make that inadvisable.
The adaptation of living here underground with a mars twists seems possible
Spanning 18 floors to a depth of 85 meters, Derinkuyu is one of the largest and deepest subterranean cities in Turkey.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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For me the skill pool determines the minimum number and the other factors determine the maximum number. Another factor I think is balancing survival against sophistication. So I think you are balancing:
1. The skill pool (for Mission One I would say this translates into "don't try too much" - no point in bringing a vulcanologist to take a look at Olympus Mons, nice though that would be). But you need to build in some redundancy - so every person with lead skills, should have an understudy who can take over in the event of the lead officer becoming incapacitated.
2. The cargo load. There's only so much emergency supply you can carry. You want to try and maximise this per capita.
3. Survival is of course the key priority, but survival isn't just about carrying lots of supplies and spares. The more sophisticated your cargo, then the greater the chances of success. So, rather than just carry stocks of food and oxygen, it will help to have a range of industrial machines (3D printers, lathes etc) and material foodstocks. It would be good if we had multiple means of acquiring water including atmospheric concentration of water vapour and regolith processing, not just drilling for pure ice.
Noah's reminder;
https://i.imgur.com/VzE9uz2.pngThe crew size is determined when the amount of mass from each incremental person slows the amount of change in ship dry mass to get man leaving Earth to go to mars as to the only thing changing are the life support quantities.
Which effects recycling numbers.
What goes into the selection process
https://www.mars-one.com/mission/mars-one-astronautsSome of the risk
https://ieeexplore.ieee.org/document/6836241Nasa Gateway mission to Phobos is a prover that we can survive
https://www.space.com/29562-nasa-manned … hobos.htmlThe Cost and Equivalent System Mass of Space Crew Time
https://spacecraft.ssl.umd.edu/design_l … e_cost.pdfThis is the one that talks to all of how the rockets are designed all the way to its surface and back to earth for the crews survival which means it covers the ballistic entry to mars
Part 1 & 2
https://space.nss.org/wp-content/upload … o-Mars.pdfThe only thing effecting growth on mars is health issues to crew under reduced gravity, extended stays for growth of population for mars. This is where we learn from the ISS for type of medical monitoring, exercise program and mediation counter action effects program. In investigation of spin tables for increased AG needs to be done as well as weighted arm, wrist, ankle plus clothing as counter measures.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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In the Expanse series, the majority of habitable structures on a heavily colonised Mars (4 billion on the TV series, 9 billion in the books) were subterranean, essentially carved into the rock of hillsides.
https://www.humanmars.net/2019/12/marti … panse.html
Following this model, the most useful construction device would be a pneumatic drill. Small rail vehicles could then be used to remove waste rock from carved out tunnels. These could be powered by gravity, with overburden emptied onto the canyon floor, or by direct electric, drawing power from a third rail.
I don't honestly know if people would be happy to live like this. It marginally reduces the amount of heating that a Mars colony would need, because food production still requires heated greenhouses and algae farms. Some enclosures may be able to rely upon the natural compressive strength of rock to maintain integrity. Others will require steel supports for spanning ceiling spaces. Much depends on the local geology. Carving out solid rock is a slow process. But it has the advantage that long term heating requirements are reduced and people are protected from the hard radiation of the surface.
Last edited by Calliban (2021-04-18 14:12:11)
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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I think it's important to have natural light, albeit possibly boosted by reflectors, light pipes or artificial natural light spectrum lights.
That's why I favoured a canyon type arrangment.
That said, with a terraced hillside and angled windows facing the outside, that would allow a lot of natural light in. Maybe you'd only tunnel in say 20 metres and then the tunnels could be connected by corridors (horizontally) and stairs or lifts (vertically). That might be quite an attractive arrangement in fact and relatively simple to construct: use earth movers to create terraces, then use boring equipment to tunnel bores at intervals into the hillside, then fill the bottom half of the tunnel floor with compacted regolith, to create a floor. Use smaller boring equipment to create connecting corridors and stairwells. Reinforce the tunnel entrance and fit window frames with thick glass at a 45 degree angle to the terrace floor.
In the Expanse series, the majority of habitable structures on a heavily colonised Mars (4 billion on the TV series, 9 billion in the books) were subterranean, essentially carved into the rock of hillsides.
https://www.humanmars.net/2019/12/marti … panse.htmlFollowing this model, the most useful construction device would be a pneumatic drill. Small rail vehicles could then be used to remove waste rock from carved out tunnels. These could be powered by gravity, with overburden emptied onto the canyon floor.
I don't honestly know if people would be happy to live like this. It only marginally reduces the amount of heating that a Mars colony would need, because food production still requires heated greenhouses and algae farms. Some enclosures may be able to rely upon the natural compressive strength of rock to maintain integrity. Others will require steel supports for spanning ceiling spaces. Much depends on the local geology. Carving out solid rock is a slow process. But it has the advantage that long term heating requirements are reduced and people are protected from the hard radiation of the surface.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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But how long and of what mass are the smaller boring machines that we use on earth? As we could sent one to mars....
Finish the grinding of what could become the first mars soils for a garden and process the ores that are high in any minerals that we would use to turn into metal items from this same chips.
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This one is for a 7.28 metre diameter cut:
https://metrotunnel.vic.gov.au/construc … hine-facts
The mass is 1100 tons and it is 120 metres long...so it would have to be moved to Mars in sections no doubt.
I think a 6 metre borer would suffice for residential space on Mars.
You'd probably have to build a rail system as well on Mars to accommodate the borer, so not sure how easy it would be to accommodate that in a terraced hillside - would probably have to be a very gentle slope.
But depending on the rock, it might just be easier to have 100 rock drill robots working night and day to create the space. They could be produced on Earth and shipped out there.
But how long and of what mass are the smaller boring machines that we use on earth? As we could sent one to mars....
Finish the grinding of what could become the first mars soils for a garden and process the ores that are high in any minerals that we would use to turn into metal items from this same chips.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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According to this site, underground homes are 20-30% more expensive than the above ground equivalent, but have lower heating costs.
https://granitehistory.org/underground-houses/
One thing that turns economics on its head on Mars, is that any construction on the surface takes place in vacuum and faces huge diurnal and seasonal temperature swings. The cold would make work difficult at night and steel would become brittle. Underground, tunnels can be pressurised and digging can be carried out without space suits. Temperature is stable and controllable, allowing low-alloy carbon steels to be used to support roof structures without fear of embrittlement. After initial heating, total heating requirements should be modest thanks to the low rates of thermal conduction through many metres of rock. So this may turn out to be the easiest way of creating habitable volume on Mars.
Some things have to be located above ground of course. Farms and landing pads, come to mind. Large factories require a lot of 2D floor space, so above ground may make more sense in this case. Nuclear power plants would be much better located underground and this has been frequently discussed on Earth. If an underground nuclear power plant suffers fuel damage, then the radioactive materials are naturally entombed.
Food could be grown underground using artificial lighting, but that approach consumes a lot of electricity. In general, low grade heat is far cheaper than electric power. A consequence of the second law of thermodynamics.
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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I quite like the idea of short tunnels/spaces being dug into a hillside. A good compromise between natural light and radiation protection. Go in about 20 metres. The space closest to the windows might be where you can cook and eat or hang out of an evening . Moving further in from the window, you would have sleeping accommodation. At the back the spaces would open on to connecting corridors, connecting all the habs and carrying the air ducts, electric cabling, and plumbing. There would be service lifts to allow for robot cleaners to move around the units. Alternatively there might be long ramps between floors, which would save on lift maintenance.
The whole hillside residential area might be connected by tunnel and air locks to a more public area where you would find automated restaurants and cafes, retail outlets, IT maintenance, etc These might be built in artificial or natural canyons.
Another tunnel might lead on to a large surface gym and leisure centre in a dome structure with swimming pool as well as gym. This might also be where you find the medical facility where even healthy pioneers will need to go for regular check-ups.
Further away still you might find the first ELE (Earth-like environment) e.g. a canyon with glass roofs and much vegetation, running water and numerous paths and cycleways.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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