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#476 2020-10-27 20:01:42

tahanson43206
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Registered: 2018-04-27
Posts: 9,949

Re: Large scale colonization ship

For RobertDyck re #475

Congratulations on taking this step to enlist Mr. Paille!  Picking up on something (I think it was SpaceNut) quoted a few posts back in this topic, good food is going to be as important in a space venture as it ever has been on Earth (submarine or surface vessel), and your choice for advice sounds like the kind of person you will (hopefully) find for ALL the specializations that will be needed.

At some point, the team you assemble will become self-reinforcing, and additional talent will be drawn in by the psychological gravitational force that accrues naturally at that point.  You're making the kind of move that seems (to me at least) just about right ...

***
Here's another suggestion ... I've been saving it for what (I hope is) the right moment ....

Not too many posts back, someone posted about the history of the US submarine fleet ... What I'm picking up on is the concept of a class of vessels ... In the US Navy, (apparently) a class of vessels gets names that are related, such as US City names, or US State names.

I bring this up because I see the potential for a (for lack of a better name:) RobertDyck class of space vessels.

I'd like to suggest that the limitations for this class be few, but very specific and very easy to understand, but also very easy to explain to a member of the public, or a government official.

SearchTerm:Specifications for RobertDyck class of space going transportation vessels

What I'm thinking about here is the set of specifications I'm working with ...

1) Width 19 meters
2) Length (of perimeter of deck) 238 meters
3) Rotation time: 20 seconds
4) Absence of bearings ... ie, the entire vehicle rotates.
5) Atmosphere same as Mars habitat [oxygen partial pressure same as Earth, inert gas pressure: ]

Edit#1: Reference: http://newmars.com/forums/viewtopic.php … 04#p171604 Oxygen

Summary:
2.7 psi O2
3.5 psi N2
1.148 psi Ar
Total: 7.348 psi total

If you then let those who are inspired by your example to try their hand at designs, you can keep the important elements while allowing some freedom of innovation to flourish in the group you assemble.

I was (guardedly) optimistic to see your mention of the possibility of more than one deck.

In a class based upon the simple elements given above (or whatever you decide upon) you could see designers trying out concepts for multiple decks and what might be done with them.

There is a category of patent law that allows for specification of designs.  In this case, it might be possible to register the elements of a class of space vessels, and then open the specification in an Open Source manner, so that everyone who uses the design understands where it came from and how to honor the spirit of the specification.

Other classes of vessel will surely come into being, humans acting as they always have, but ** this ** class should be able to earn a place in history, just as Elon is doing with his Starship concept. 

(th)

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#477 2020-10-28 05:51:55

RobertDyck
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Re: Large scale colonization ship

You're ignoring a couple key issues. The problem of mass creep is a major issue; NASA has designed vehicles that grow and grow becoming very expensive and unwieldy. Keeping size to the original design is a major problem.

And gravity. In post #443 I responded to an issue that SpaceNut raised: difference between acceleration of a person's feet and head. For a 6-foot man at the top of his head would be 95.149% that of his toes. But look at the difference between decks: acceleration for the floor of the ring is 0.3794121236482875 g, while the floor of the roof is 0.3534464989397372 g. That means the roof has artificial gravity 93.156% that of the main ring. And you suggest more floors/decks? The closer you get to the centre of rotation, the greater the difference between one deck and the next.

Even with just two decks, you don't want anyone to spend a lot of time on the roof. Giving the gym two floors allows it to take less deck area. The cost is the upper deck has several issues. The upper deck will not have radiation shielding, so is not part of the shelter in case of a solar radiation event. But lower acceleration (artificial gravity) means you cannot place a running track up there, cannot place an treadmills. You can place exercise machines, but it requires resistance based machines rather than weights. So "bowflex" instead of machines with weight plates. To keep mass of the ship down, that's a good idea anyway. But also no treadmills, but you can place exercycles. Yes, you can walk up there, but the idea is to get used to Mars gravity. Mars surface gravity is 37.94% that of Earth, not 35.34%. Exercise in the lower gravity will not exercise your body as much: weight lifting 10kg mass is 10kg mass, but your muscles respond to stress. That stress is dependant on weight, not mass. In 37.94% gravity a 10kg dumbbell will provide 3.794kg-force of weight. In 35.34% gravity it will weight 3.534kg-force. I could work that out in newtons, but I think kg-force makes more sense. At least for a gym. And physical coordination for running will be quite off due; you want people to become acclimated to Mars gravity, for their reflexes to adjust for Mars gravity, not something else. One reason for not placing any cabins on upper deck(s) is avoid muscle and bone atrophy beyond Mars gravity.

On Earth the difference between one floor and the next is not significant. Earth's mean radius is 6,371.0 km, that's 6,371,000 metres. Measured to 4 significant figures there's a difference of equatorial vs polar radius. Our ship has a radius of 37.6992 metres. Difference of 2.58 metres from one floor to the next is not significant over 6 million plus metres, but over a radius of just 37.6992 metres it is.

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#478 2020-10-28 07:12:34

tahanson43206
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Re: Large scale colonization ship

For RobertDyck re #477 and topic

These are still early days! Thanks for giving the question of multiple decks serious thought, and for the details you have provided for those who are interested in study of the problem.

Please concentrate on creating an environment that humans will ** want ** to occupy for two years.  That will require some minimal investment.  You can ** always ** cut back if your funders run out of resources or enthusiasm. 

Regarding floors ... who says you have to go ** in ** toward the hub?

The specification calls for rotation every 20 seconds.

The starting point (and a minimal requirement) is Mars gravity.

The outer deck could be outside the cabin deck, leaving the inner surface for the green house, which I find a most interesting concept.

Storage of supplies could be done in the central shaft, which your original description sounded (as I remember it) to be empty.

There is no limit to the length of that central shaft, other than your self-imposed mass limit.

However, I come back to my theme ... If you set the minimal specifications, and encourage your followers to create designs which adhere to them, then you'll see a wide range of interesting concepts, one or more of which will receive funding, and the entire venture will achieve visibility.

(th)

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#479 2020-10-28 07:40:29

RobertDyck
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Re: Large scale colonization ship

Actually you're right. I said the hub would be reception, docking for a shuttle. I envision using a SpaceX Starship to shuttle passengers from the surface of Earth to the ship in Earth orbit. Another Starship will be permanently parked on Mars, used to shuttle passengers from Mars orbit to the surface. It could be used for zero-G fun and games during transit. But aft of the zero-G hub will be cargo storage, including food supplies. The kitchen will have to have someone regularly carry groceries from storage in the cargo hold to the kitchen for use. Luggage that passengers do not require access to during transit as well as any major cargo such as Mars construction supplies will be carried there. Aft of the cargo hold will be propellant tanks, and finally main engine. Sewage storage will also be at the hub; GW Johnson suggested a separate module that could be detached to carry sewage to the surface of Mars as fertilizer. That's a good idea. So attached to the outside, on sides of the zero-G hub. Eg, 3 sewage modules, one between each spoke to keep mass balanced.

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#480 2020-10-28 09:11:30

tahanson43206
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Re: Large scale colonization ship

For RobertDyck re #479

Thank you for this helpful post ...

SearchTerm:Hub Draft description of contents of hub for Circle Y design space transport

http://newmars.com/forums/viewtopic.php … 63#p173463

***
New (old) topic .... in reviewing your specification for atmosphere for air in a Mars habitat (and therefore the ship) I found 2.7 psi suggested.

Is there a technical reason this could not be rounded up to 3?  I'm asking for the simple (practical) reason that three is easier for a human being to store in memory. There are three spokes, gravity is (about) 1/3 of that of Earth, and the oxygen pressure should be held at 3 psi.

The memory aid wouldn't work if the pressure is specified in other units.  For example, Google reported partial pressure of oxygen at sea level is 160 mm Hg.

Please give some thought to a mnemonic that could be used by crew to remember the correct (desired) settings for atmosphere partial pressures to be maintained in the ship habitat volumes, and in Mars habitat volumes.

As I understood your post about atmosphere, you were going for the ability to move quickly and easily between habitat and environmental suit without having to deal with long waits to prevent "bends".  Can you design the mixture of gases so it meets your practical criteria while being easy for humans to remember?

Whatever you come up with would (presumably) become gospel for future generations, who will have no idea where it came from, but who will learn it by rote to stay alive on Mars or in transit.

(th)

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#481 2020-10-28 11:38:23

RobertDyck
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Re: Large scale colonization ship

Partial pressure of oxygen on Earth at sea level is 3 psi. Spacesuit pressure for Mars is also 3. Habitat is 10% lower. If your suit gets a pressure leak you can endure 10% loss and it's still what you're used to. A trick NASA had planned to use for Apollo.

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#482 2020-10-28 17:47:20

tahanson43206
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Re: Large scale colonization ship

For RobertDyck re #481

Thanks for reply with partial pressures on Mars for suit vs habitat.

SearchTerm:Oxygen partial pressure Mars habitat Mars suit
SearchTerm:PartialPressure oxygen in Mars habitat Space ship Mars suit

http://newmars.com/forums/viewtopic.php … 67#p173467

While I don't recall your making a point of it, I presume the Mars suit practice could/would be extended to space travel situations, where crew need to go "outside" during a voyage.  It would not be a common occurrence, I'm sure, but voyage planners will presumably insure the capability is part of preparations.

Thanks for the Apollo reference ...

As an explanation for someone coming upon this conversation for the first time ... What RobertDyck has in mind is providing a way for humans on Mars (or in transit to Mars) to exit the habitat in a suit without having to spend time adapting before and after an away period.

***
For RobertDyck ... to the best of my knowledge the recommended atmosphere pressures have not yet been tested in space.  While the logic of the recommendation seems reasonable (to me at least) it would be helpful to test it with real subjects in orbit, before committing a crew to it for a voyage to Mars.

This is another reason to seek funding to build a prototype of your proposed ship design in LEO.

Historical reminder ... Apollo used pure oxygen at 5 psi for space flight after launch ...

https://www.nasa.gov/feature/50th-anniv … result-of/

The board concluded that astronauts would continue to breathe pure oxygen in their space suits before and during launch to reduce the risk of developing the bends or decompression sickness, since once in orbit the CM’s environmental control system would gradually replace the mixed-gas atmosphere with pure oxygen and reduce the pressure to 5 psi, standard orbital operating conditions for all US spacecraft at the time.  The LM’s atmosphere, since that module wouldn’t be occupied until well into the mission, would be maintained with pure oxygen at 5 psi.  The decision on cabin atmospheric composition and pressure took NASA one step closer to manned Apollo flights and landing a man on the Moon before the end of the decade.

The proposal by RobertDyck is to use a mixture of gases in the habitats on Mars and in space vehicles traveling to Mars (and presumably returning from Mars), and to use pure oxygen in Mars suits and presumably in space suits during a voyage.

For details of the gas mixture proposed by RobertDyck for the habitat, see:
http://newmars.com/forums/viewtopic.php … 56#p173456

(th)

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#483 2020-10-29 06:34:01

tahanson43206
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Re: Large scale colonization ship

Reserved Post:

This post in Large Ship topic is reserved for a communication from a (small) investor with contacts in the community.

I requested and received an evaluation of prospects for RobertDyck to receive funding for his transportation concept.

The contributor has agreed to be identified as FriendOfQuark#1

I'm probably not the best person to weigh in on the kind of investing that is going to be needed.  The "investing community" is not monolithic and is clearly divided by regulations.  Regular retail investors like me are prohibited from buying the sort of securities Dyck would initially be selling.

For an early stage project you are going to need exclusively "accredited investors" or the foreign equivalent as defined by the foreign version of the SEC in whatever country(s) you raise capital in.  For something like this, you would ordinarily start with an "angel" venture capital group.  The most common type (in the US) is limited to 100 participants.  They will generally lock up capital for 7 to 10 years and a management team will allocate across several investments.  Note the 7-10 year period.  These investors have a less than eternal time frame and expect to cash out within a decade.  You'll need a sustainable revenue stream in that time which is moving pretty damn fast for a space tech company.

There is a later stage VC company that is focused on space, I called the "Space Fund".  They are working on putting their VC on a blockchain to "tokenize" the investments.  They will then be able to focus on 20-30 year investing horizons (which is more in line with how long it typically takes space companies to start generating revenue) and investors can divest via selling their (hopefully appreciated) tokens to new accredited investors at the common 10 year mark.  I have a 2nd order contact with a senior person there (she spoke at one of our local NSS meetings) who might be able to offer some pointers on how to be attractive to her fund.  Check out their "reality rating" page - Reality Rating | SpaceFund where they handicap how likely a space venture is to reach a "reality" level of development.

***   
Reality Rating | SpaceFund

The SpaceFund Reality rating (SFR) provides critical, intelligent, and thorough information about the status of ...
***

I think some cold water is due though.  (Sorry).  The size of the vessel in question is quite a lot larger than an ocean going cruise ship.  Those currently go for about $3 billion USD a piece and that is before you lift the components to orbit and assemble them. Say this is a $50 billion project.  You'll need a VC company that has several times 50B to invest so they can diversify their risk.  With the cohort likely limited by law to 100 participants, you need 100 billionaires to get on board with a cool couple/three billion bones each to fund fully.  You can always partially fund it and raise more funds in IPO but who is going to buy the IPO shares of a company that claims it is sending 1000 people to Mars but doesn't have the tonnage in orbit?  It is a catch-22.

I think mr Dyck has an interesting and important exercise.  But not one that can realistically be financed due to scale.  Do it anyway.  Learn from the process.  Copyright/patent the work product and see if it can be licensed out to the mega billionaire cowboy capitalists like Bezos, Musk, Branson, Beal, etc.  That is a company that is small enough to attract initial investment capital and ultimately grow into something more ambitious.

Quoted with permission.

(th)

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#484 2020-10-29 07:15:47

RobertDyck
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From: Winnipeg, Canada
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Re: Large scale colonization ship

NASA had intended to use 3.0 psi pure oxygen inside the Apollo Command Module prior to the Apollo 1 fire. That test was designated AS-204, a Congressman renamed it "Apollo 1" posthumously. They tested the command module with 16.7 psi pure oxygen. The manufacturer North American sent a memo in which they clearly stated to *NOT* do that! But NASA had done this test with Mercury and Gemini, so they believed it was safe.

Atmospheric pressure on Earth at sea level is 14.69595 psi. Earth's atmosphere has 20.946% oxygen. That means Earth at sea level has 3.07821 psi partial pressure oxygen. NASA intended to stress the capsule with the same "gauge" pressure as it would experience in space, meaning same pressure inside vs pressure outside. In space outside has zero pressure, it's vacuum. KSC is on the coast so at sea level, so that should have been 17.7 psi, but they used 16.7 psi.

Human lungs respond to partial pressure of oxygen. Not exactly that simple, but close enough. Combustion (burning) doesn't work that way. Things burn in 3.0 psi almost as slowly as Earth at sea level. Other gasses get in the way, cause combustion to act more slowly, but it's close. Combustion in 16.7 psi pure oxygen is radically different! They used velcro all over the Command Module to stick things to walls so they don't float away: pens, clipboard, etc. North American gave a maximum total area of velcro, but astronauts liked velcro so total amount in the test CM greatly exceeded the maximum. North American had removed insulation from many wires to reduce weight. But a forensic study of the CM after the fire showed it started in the hinge of the door. Frayed wires started fire. North American prepared a demonstration for NASA: velcro in a sealed container with normal air, and a lighter to start a fire. The velcro smouldered, but as soon as the lighter was turned off, the fire stopped. The second sealed container had 100% pure oxygen (at ambient air pressure). The velcro went up light the head of a match.

I could also cite tests done by the US Air Force with pilots breathing 100% oxygen at 3.0 psi, 2.5 psi, and even 2.0 psi. At 2.0 psi even the strongest pilots remained conscious for only 30 minutes. All test subjects were in their prime, strong and healthy, and completed high altitude training. Pilots could breathe 2.0 psi partial pressure oxygen if total pressure was higher, but with pure oxygen 2.5 psi was lowest to remain conscious and operate the complexities of an aircraft. They found at 3.0 psi pure oxygen, anyone could do it, high altitude training was not necessary.

Before the fire, NASA intended to use 3.0 psi pure oxygen in the Command Module, and 3.3 psi pure oxygen in spacesuits. After the fire they made some changes. They used ambient air at launch, but the spacecraft "bled" air as it gained altitude, it air was flushed out with pure oxygen. When they parked in Earth orbit, air in the capsule was stable at 5.0 psi pure oxygen. They had considered using a mix of oxygen and nitrogen, but having two separate gas tanks and regulation equipment to maintain the correct balance was considered too complicated. To reduce weight they used pure oxygen.

Skylab did use 5.0 psi total pressure with 60% oxygen / 40% nitrogen. That means 3.0 psi partial pressure oxygen, and 2.0 psi partial pressure nitrogen. Once astronauts entered Skylab and started breathing, some oxygen was consumed and they exhaled CO2. Sweat and breath added water vapour. But you get the idea.

Russian Soyuz spacecraft used air with pressure equal to the Baikonur Cosmodrome in Kazakhstan where they launched. This required the Apollo-Soyuz project in 1975 to include an airlock to connect the two capsules.

Air pressure at higher altitude is lower. Based on the same percentage oxygen as the rest of the planet, partial pressure of Boulder Colorado works out to 2.54 psi. So my recommendation of 2.7 psi O2 for Mars is hardly extreme.

My recommendation in post #476 was:
2.7 psi O2
3.5 psi N2
1.148 psi Ar
Total: 7.348 psi total = 1/2 Earth atmospheric pressure at sea level

As stated in that post, there's a ratio of maximum nitrogen in the higher pressure environment to total pressure in the lower pressure environment. If you exceed that, decompression will cause the bends. You can deal with it by prebreathing pure oxygen for hours to flush nitrogen out of your blood prior to decompression. But to avoid that, you have to adhere to this maximum. That ratio is 1:1.2, total pressure to partial pressure nitrogen. So if the spacesuit uses 3.0 psi total pressure, then the maximum nitrogen in the habitat to avoid prebreathing is 3.0 x 1.2 = 3.6 psi. I recommended dropping nitrogen a little just to avoid the hairy edge of disaster.

You can add argon increase total pressure. Earth has 0.9340% argon, so you're actually breathing O2/N2/Ar right now. There's also a maximum amount of argon without prebreathing oxygen. As long as you don't add too much argon, you're fine.

Notice I recommended 7.348 psi total pressure for a habitat on Mars. Apollo used 5.0 psi pure oxygen. Skylab used 5.0 psi with 60% O2 / 40% N2 mix. What I'm recommending is even less extreme. It's fine.

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#485 2020-10-29 08:15:46

tahanson43206
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Re: Large scale colonization ship

For RobertDyck re #484

Thank you for more detail about Apollo era planning for atmosphere for various vehicles.

Thank you for more detail about the factors that must be considered for planning atmosphere for future habitats on Mars and in space vehicles.

For a variety of reasons, it seems to me your "sweet spot" design is likely to gain visibility and eventually acceptance.

However, the ** best ** way to insure your recommendation becomes the standard for human travel away from Earth is to actually implement an example.

As FriendOfQuark#1 offers in a post shortly before this one, there are avenues for funding via private individuals that may well be worth pursuing.

However, I think that a mission to test the model you have recommended would appeal to government agencies.

My recommendation in post #476 was:
2.7 psi O2
3.5 psi N2
1.148 psi Ar
Total: 7.348 psi total = 1/2 Earth atmospheric pressure at sea level

SearchTerm:SweetSpot RobertDyck recommended atmosphere for Mars habitat and for space vehicles to permit EVA without wait time.

These recommendations need to be tested in space, and the sooner that happens the better.

Thanks for the reminder that Argon can cause bends.  I recall there were posts earlier in this topic where that was discussed.

(th)

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#486 2020-10-29 13:47:50

RobertDyck
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From: Winnipeg, Canada
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Re: Large scale colonization ship

I posted about a lot of the testing that has already been done. If you feel further testing is required, that can be done on the ground. Atmosphere is atmosphere; there's no difference between space vs ground with regards to air we breathe.

One real research project is developing a mechanical counterpressure (MCP) spacesuit. Initial work done by Dr Paul Webb in 1967. Dr Dana Newman said in an interview that developing an MCP suit that works at 20 kPa is easy, but 30 kPa is hard. What I would like to counter is then just use 20 kPa. Duh! 20 kPa = 2.90 psi, 30 kPa = 4.35 psi. 3.0 psi is 20.684 kPa, so she just rounded. The initial prototype built by Dr Webb in 1967 used 170 mm.Hg (millimetres mercury) = 3.287 psi. Again, NASA was planning on using that pressure for Apollo spacesuits at that time. Apollo suits ended up using 3.7 psi pure oxygen. EMU suits used on Space Shuttle and ISS use 4.3 psi pure oxygen. The reason is Shuttle and ISS use 1 atmosphere pressure, meaning the same pressure as sea level. Astronauts must prebreathe pure oxygen for 17 hours before decompressing to suit pressure. And the suit has higher pressure reduce prebreathe time and decompression time. Of course if they used Skylab pressure instead then they could use the same pressure as Apollo A7L spacesuits without any prebreathe time, and much less decompression time. In fact, we could use 3.0 psi suit pressure.

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#487 2020-10-29 14:08:03

RobertDyck
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Re: Large scale colonization ship

Radiators that NASA used for American parts of ISS are made of inconel. That's the same metal that I suggested for heat shields and back shell for precious metal bullion dropped to Earth. So asteroid mines will make that alloy. NASA identified inconel 617 for metal heat shields.

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#488 2020-10-30 05:50:06

tahanson43206
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Re: Large scale colonization ship

For RobertDyck re #486

I agree that atmosphere testing can be done on Earth, and recommend that a project plan to lead toward launch of a Large Ship should include funds and procedures to certify that the atmosphere you have proposed will work with actual personnel over a period of weeks rather than just a day or a few hours.

While the logic of your recommendation seems solid (to me at least) there may be factors never seen before by humans, so testing is a vital activity to be completed.  Testing should be down with a variety of persons to insure the balance you have tried to strike will work for as many people as possible.

Speaking of project plans ... it is time (in my opinion) for a project plan to begin to crystalize.  My recollection is that there are free project planning sites available these days, although I've not had an occasion to use one of them.

For SpaceNut ... if you would have a few minutes to spare, a search for a project planning web site that would meet the unique requirements of this forum would be helpful.

For RobertDyck ... FriendOfQuark#1 offered some thoughts which I have posted a few days back ... please take a look at them and offer some feedback.

You're going to need ** lots ** of help to pull this off, and it is easy for offers of assistance to escape attention in the heat of the creative flow.

(th)

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#489 2020-10-30 10:02:29

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
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Re: Large scale colonization ship

I am a senior computer software developer. I have been a computer technician the last 3 years, but have held fancy titles such as Technical Architect of the Year 2000 project management office for the Manitoba Telecom Services, or Information Systems Specialist for the department of Social Services for the City of Winnipeg. I have used project management software, setting up a PERT chart from scratch using Microsoft Project or a more elaborate project management software that MTS used in 1998 and is no longer sold.

I grew up with the view that you start small and grow. Setting up something this large requires a lot of infrastructure. The concern is too much infrastructure will require a lot of time. However, that infrastructure can reduce cost for a very large ship such as this. So my plan was build a business:

  • manufacture high efficiency solar panels: 8-junction gallium-indium-nitride discovered by Los Alamos National Laboratory. I posted about them a few times. That lab hired University of California in Berkeley to build a prototype to prove it works. I read about it in the journal Science in year 2000. No one is building them. One advantage of this chemistry is all junctions have the same chemistry, just a different concentration of nitride. An 8-juction cell converts 70% of sunlight to electricity! Panels you can buy at home improvement stores today convert 14%, so we're talking 5 times the amount of electricity. Panels for satellites are the highest efficiency currently in production, way too expensive for a house, but they produce 32% efficiency. The 2 corporations that produce space cells in the US have a long term plan to slowly increase efficiency over multiple decades to 45%, gouging their customer with every fraction of a percent increase as they go. They certainly have no intention to jump straight to 70%. Fine, so I want to make ones optimized for houses on Earth.

  • build houses with solar roof. Not just some panels attached to the roof, but the entire roof is entirely solar panel. Geothermal heat pump, batteries in the basement, helical windmill in back yard, and well insulated. Result designed for 100% energy independence under worst case weather conditions here in Canadian cities. The other 51 weeks per year it will generate surplus electricity. The power will flow one-way only, from the house to the grid. The electric utility will pay the home owner every month, not a bill. Some have asked if everyone does this, then who buys the power? This works for houses and low buildings, but doesn't work for factories or tower buildings, eg office towers or apartment towers. So there will always be someone to buy the power. With windmill and solar, if weather is cloudy it'll be windy, so when solar generates less, windmillls generate more. Helical windmills operate with gusting wind rapidly changing directly, so work close to the ground in built-up areas such as a suburb. And they look pretty, and don't kill birds.

  • build kits to convert used cars to all electric. Especially targeted at models of cars used as host for body kits. I won't sell body kits, just power train kits.

  • start asteroid mining. Automated equipment at the asteroid, no humans. Produce inconel 617 and use a 2-part mould to make a heat shield. Another 2-part mould to make a back shell. Refine platinum and plantium group metals into pure bullion. Gold and silver are difficult to separate from each other, so don't even try. If "gold" bullion is 98% gold/silver alloy with 2% industrial metals (copper, etc) then good enough. They can be refined on Earth. Or sold as 10 to 18 carrot gold. Leave iron and nickel billets at the asteroid. Produce 300 series stainless steel at the asteroid. Also billets of inconel. Choose a NEA, closer to Earth than Mars or Venus, but at least 1km diameter.

  • build a rolling mill in Earth orbit. Roll billets of stainless steel into sheet metal suitable to manufacture the ship hull, and micrometeorite shield. Roll billets of inconel into radiators for the ship.

  • build a mine on the Moon. Find a nice deposit of highly pure anorthite on the surface, that's igneous and most of the Moon is alumino-silicate. Anorthite can be chemically treated to become aluminum hydroxide, then calcinated to make aluminum oxide. That can be smelted with electrolysis to make aluminum metal. Aluminum oxide and aluminum nitride can be made into ALON for windows of the ship.

  • sell ALON windows on Earth first. So we can prove we know how to make it. ALON would make great storefront windows. Cannot be broken by simply throwing a rock or brick into the window. Jewellery stores or other stores in high crime areas would buy windows that cannot be broken by rioters or petty thieves.

  • mine a C-type asteroid for ice. Melt ice, use electrolysis to make hydrogen and oxygen. Chill to liquid as rocket fuel. A C-type asteroid has tar, that can be refined for hydrocarbon fuel, or combined with hydrogen to make methane. Or converted to CO2 for transport to the metal asteroid. First step of processing a metal asteroid is the Mond process, which requires copious quantities of carbon monoxide. That can be transported as dry ice (CO2), then processed at the metal asteroid with hydrogen to make CO. Highly pure water ice can be transported as an easy means of transporting hydrogen. An NEA would be nice, but a couple astronomers tell me it's unlikely asteroids close to the Sun will still have ice. Asteroids with ice will have to orbit the distance of Mars or farther. Some astronomers question that, stating large asteroids could still have ice. But both moons of Mars have the same spectral signature as C-type asteroids. If one of them still has ice, that would be the ideal source of volatiles!

  • start construction of the ship. Use robots aka construction drones for work in space.

Developing the Earth based arms of the company can be done with profit within 10 years.

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#490 2020-10-30 11:03:37

tahanson43206
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Registered: 2018-04-27
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Re: Large scale colonization ship

For RobertDyck re #489

Thank you for your detailed reply!

SearchTerm:BusinessPlan RobertDyck Large Ship Project

This post is an anchor for study later.

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#491 2020-10-30 14:32:26

RobertDyck
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Re: Large scale colonization ship

We could certainly use a large team. Another Earth project is life support. Genetically engineer a pea plant, the chromosome that produces chloroplast plasmid. Add genes from cyanobacteria for all 3 recycling pathways for 2PG. This should greatly reduce photorespiration, consequently increase crop yield. A company that produces peas on industrial scale should be willing to finance this research. We'll ensure we retain rights for use in space. This will produce chloroplasts that will function in-vitro long enough to be practical as oxygen generator for life support.

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#492 2020-10-30 15:40:42

GW Johnson
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From: McGregor, Texas USA
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Posts: 4,820
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Re: Large scale colonization ship

Here is the list of stuff I have posted that is relevant to spacesuits and breathing atmospheres.  It was a learning process,  so the later stuff is better.  The site is my "exrocketman" site:  http://exrocketman.blogspot.com.  To look by keyword,  use the navigation tool on the left to find an article with that keyword label,  by its year,  month,  and title,  then go to the end of the article,  and click on the "spacesuit" keyword.  It will then show all (and only) the articles bearing that keyword.

GW

articles by keyword "spacesuit" that deal with pressure and mix of gases for spacesuits and habitats in space

1-21-11  Fundamental Design Criteria for Alternative Space Suit Approaches

12-13-13 Mars Mission Study 2013

12-11-14 On-Orbit Repair and Assembly Facility

11-17-14 Space Suit and Habitat Atmospheres

1-15-16 Astronaut Facing Drowning Points Out Need for Better Space Suit

2-15-16 Suits and Atmospheres for Space

11-23-17 A Better Version of the MCP Space Suit?

3-16-18 Suit and Habitat Atmospheres 2018


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#493 2020-10-30 19:24:06

tahanson43206
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Re: Large scale colonization ship

For GW Johnson ... thanks for the references to study !!!

As a short cut ... how do you evaluate RobertDyck's recommendation?

Can you live with it?

#485 above has a summary of his recommendation for the habitat.

To save you time, here it is again:

My recommendation in post #476 was:
2.7 psi O2
3.5 psi N2
1.148 psi Ar
Total: 7.348 psi total = 1/2 Earth atmospheric pressure at sea level

In order for RobertDyck's project to get anywhere, it is vital to nail down some of the ever shifting parameters.

RobertDyck has advertised this atmosphere composition as having the capability of:

1) Meeting human requirements in a habitat or in a space vehicle
2) Allowing humans to transition to all-Oxygen environment suit or space suit without prebreathing or post-excursion delay.
3) Providing a margin for error in case of a leak in an environment suit or space suit

Edit#1: In another part of the NewMars archive there is at least one detailed study of the optimum growing environment for plants.  I'll have to go back to check, but I ** think ** the sweet spot was 2 (something) CO2 in a mix of gases.  It might have been 2 % ... there's a ** big ** difference.

RobertDyck has shown interest in planning a greenhouse deck above (inside) the cabin deck.

It would be good to know if humans can tolerate 2 (?) CO2 (if that is the correct figure).  In that case pressure could be the same in the two sections, and only simple air tight doors would be needed to keep the greenhouse atmosphere from leaking into the cabin space.

Edit#2: http://newmars.com/forums/viewtopic.php?id=9257

Edit#3: Here is a post in which SpaceNut found text giving CO2 levels in ppm.  2000 ppm is the value I was trying to remember above.

However, 2000 ppm value does not translate late directly to psi for the proposed atmosphere for Mars habits given by RobertDyck.

What does come directly from the 2000 ppm value is percentage ... thus, for the 1/2 standard Earth atmosphere RobertDyck has recommended, the 2000 ppm value would equate to .2% (2 tenths of 1 percent) of the total complement of molecules.

Assuming percentage of molecules translates to psi (which it may not) then .2% of 1/2 standard Earth atmosphere would be .002 * 7.348 psi, or 0.014876 psi.

Google came up with this:

350 to 1000 ppm is a good quality concentration in an enclosed room. This is what the Earth is, a confined space. 1000 to 2000 ppm, the air quality is low. From 2000 to 5000 ppm, CO2 concentration starts to cause problems (headaches, insomnia, nausea).Oct 23, 2013

Effects of CO2 in humans – Aragon Valley

So! it would appear that humans can tolerate a concentration of CO2 that is in the favorable range for plants, with 2000 ppm being at the high end of what is good for plants, and also at the high end of what is tolerable for humans.

SearchTerm:CO2Tolerance 2000 ppm
SearchTerm:CO2Plant Optimum Top 2000 ppm

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#494 2020-10-31 06:43:52

SpaceNut
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Posts: 25,306

Re: Large scale colonization ship

What I note is that we only need half as much energy to develop from scratch the air to breath and that if we make use of any left over oxygen that might be remaining in the rockets fuel tanks we get a much lower energy cost to produce.
Second is that the space suit matches the values mean we need no pre-breathing.

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#495 2020-10-31 08:32:48

RobertDyck
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Re: Large scale colonization ship

tahanson43206: humans can breathe 2% CO2 at 1 atmosphere pressure, but you really don't want to. At 2% it'll give you a headache. CO2 on Earth is 0.0415% as of September 2020. Increasing to 0.10% would help plant growth. Since the ship will have 1/2 atmospheric pressure, double the percentage for the same partial pressure.

Actually, increasing to 10% CO2 would significantly enhance plant growth, but that much (at least at 1 atm pressure) is lethal to humans.

Rather than something fancy to increase CO2, I suggested just blowing air from the gym directly into the greenhouse.

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#496 2020-10-31 08:44:57

GW Johnson
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From: McGregor, Texas USA
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Posts: 4,820
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Re: Large scale colonization ship

Tahanson43206: 

I got pretty much the same atmosphere that RobertDyck got,  in that latest article in my list, which was 3-16-18's "Suit and Habitat Atmospheres 2018".  I just did it without any argon,  staying with a variant of synthetic air (oxygen-nitrogen mixture).  The equipment for a two-gas mixture is simpler than the equipment for a 3-gas mixture.  That latest one is the best one,  and has the widest range of possibilities.

While doing all this, I paid attention to three phenomena:  (1) fire danger (limited to Earthly sea level air concentration of oxygen),  (2) the 1.2 ratio of partial pressures of nitrogen and oxygen (to eliminate pre-breathe times),  and (3) the displacement effect of water vapor in the lungs reducing partial pressure of oxygen there (not to get below that in Earthly air at 10,000 feet altitude).  I looked at a range of pure oxygen suit pressures from the min wet in-lung partial pressures upward,  and used the 1.2 ratio to set 2-gas hab pressures.  I worked upward until I hit the fire danger criterion.   I ended up at about 45% oxygen in a 6.5 psia atmospheric pressure for the hab.

I also looked at having a different mix at a higher pressure in those parts of the habitat where pregnant women and young children might be located.  They would not be going outside,  so prebreathe time is not an issue.  A little more pressure (near 10-11 psia) at a lower % oxygen (20.9%) is what we evolved in,  so don't mess with the biology,  just get on with accommodating it.

There's no pre-breathe to go through an airlock from one section to the other.  You just need the pressure change.  Those folks who might be going out in suits are located in the lower pressure,  higher oxygen zone. EVERYBODY has adequate to more-than-adequate wet in-lung oxygen partial pressure,  which is what drives oxygen diffusion across the lung membranes into the blood.

The solution space only exists if you start looking at oxygen partial pressures at altitude instead of sea level. We don't all live at sea level,  and most all of us do well up to 10,000 feet. That's fundamentally why I did what I did in the article.

GW

Last edited by GW Johnson (2020-10-31 08:48:26)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#497 2020-10-31 09:07:58

tahanson43206
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Registered: 2018-04-27
Posts: 9,949

Re: Large scale colonization ship

For RobertDyck re #495 ... thanks for follow up re CO2 levels ...

For GW Johnson re #496 ... thanks for confirmation RobertDyck is/was in the ballpark of your work, ** but ** thanks for the reminder about pregnant women and young children!

The atmosphere Large Ship RobertDyck is working on (in this topic and perhaps elsewhere) would appear to be optimized for adult humans.

If pregnant women or young children are to take passage, your post is a reminder that planners might do well to provide a full Earth-normal atmosphere (similar to the ISS) and simply make that section separate from the rest of the ship.

In an earlier post in this topic, I updated the note about the greenhouse to clarify that earlier research (reported elsewhere in the forum)  would appear to indicate that 2000 ppm is a sweet spot for CO2 concentration for plants and humans.   Plants achieve maximum performance (not all plants) at 2000 ppm, and humans can still tolerate that concentration without ill effects.

RobertDyck suggested routing air loaded with CO2 from the habitat section into the greenhouse, and while I like the sound of that, it would require removal of a comparable volume of air from the greenhouse ** without ** CO2.  ** That ** strategy may turn out to be better.

Work on Earth to remove CO2 from the air is in progress with some urgency due to fears of Climate Change.   Equipment developed to perform ** that ** function would seem well suited to perform a similar service at the exit port of the greenhouse deck of RobertDyck's Large Ship.

From the stand point of coming up with something ordinary humans can remember, I am cobbling together what I ** think ** I am hearing from the two of you, as follows:

Set habitat level to 1/2 Earth sea level, with oxygen partial pressure at 3 psi less 10% for EVA safety margin.

Set habitat CO2 level at less than 2000 ppm (evacuate air to greenhouse in continuous circulation)

Set greenhouse CO2 level at maximum 2000 ppm for the plants.

Remove ** all ** CO2 from air returned from the greenhouse to the habitat (that's a goal... not achievable in practice)

Provide default 3 psi Oxygen for EVA activity, allowing for leakage of 10% to habitat normal.

Per GW Johnson ... for Earth-Mars ship, go with Nitrogen as the inert gas.

At Mars, since Argon is available, employ Argon to supplement Nitrogen in habitats.

At Mars and in transit, provide Earth sea level pressure and gas mixture for pregnant women and young children.

SearchTerm:Atmosphere summary of discussion (RobertDyck/GW Johnson)
SearchTerm:Habitat pressure
SearchTerm:Pressure habitat


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#498 2020-10-31 09:12:14

RobertDyck
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From: Winnipeg, Canada
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Re: Large scale colonization ship

2000 ppm = 0.2%

ppm means parts per million, so divide by 1,000,000 then multiply by 100 to get percent.

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#499 2020-10-31 09:47:19

tahanson43206
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Registered: 2018-04-27
Posts: 9,949

Re: Large scale colonization ship

For RobertDyck ... re #498

Thank you for the clarification of the point about ppm for CO2 in the green house.  The prior post is updated to show that.

This post includes a set of Google snippets about an instrument developed by JPL (apparently) that is in test at the ISS, and intended for Orion moon flights.

It should be relevant to the Large Ship project ... This is only a monitor, but it can guide atmosphere maintenance machinery:

About 5,260,000 results (0.50 seconds)
Scholarly articles for spacecraft atmosphere monitor
Progress report on the spacecraft atmosphere monitor - Madzunkov - Cited by 9

S.A.M. Goes to Work Aboard ISS | NASAwww.nasa.gov › feature › nasas-spacecraft-atmosphere-...
Jul 29, 2019 — NASA's Spacecraft Atmosphere Monitor Goes to Work Aboard the International Space Station. NASA is validating modern crew health ...

Spacecraft Atmosphere Monitor - Wikipediaen.wikipedia.org › wiki › Spacecraft_Atmosphere_Mon...
The Spacecraft Atmosphere Monitor is a machine that is being tested on the International Space Station to check on the health of the astronauts on it. It ensures that the air quality in the spacecraft is free of gas contaminants. It is planned on being used during the Artemis program in the Orion spacecraft.

The Spacecraft Atmosphere Monitor (S.A.M.) for ISS and Orionwww.hems-workshop.org › Talks › Kidd
PDF
The Spacecraft Atmosphere Monitor. (S.A.M.) for ISS and Orion. Richard D. Kidd. Senior Technologist, Planetary Surface Instruments Group. Jet Propulsion ...

NASA Explores - The Spacecraft Atmosphere Monitor (aka ...www.facebook.com › NASAExplores › photos › the-sp...
The Spacecraft Atmosphere Monitor (aka S.A.M.) is hard at work aboard the International Space Station. NASA Jet Propulsion Laboratory scientists and ...

The Technology Demonstration of the Spacecraft Atmosphere ...ttu-ir.tdl.org › handle
Jul 7, 2019 — The Spacecraft Atmosphere Monitor (S.A.M.) is a miniaturized Gas Chromatograph Mass Spectrometer (GC/MS) instrument being sent to the ...
by S Schowalter · 2019 · Cited by 1 · Related articles

File:Spacecraft Atmosphere Monitor.jpg - Wikimedia Commonscommons.wikimedia.org › wiki › File:Spacecraft_Atmosp...
Aug 20, 2019 — English: The Spacecraft Atmospheric Monitor is being tested on the ISS and is planned on being used during the Artemis program. Date, 24 ...

(PDF) Progress Report on the Spacecraft Atmosphere Monitorwww.researchgate.net › publication › 305426943_Progre...
Jul 19, 2016 — PDF | The Spacecraft Atmosphere Monitor (S.A.M.) is a miniature gas chromatograph (GC) mass spectrometer (MS) intended for assessing ...

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#500 2020-10-31 10:01:38

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,241
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Re: Large scale colonization ship

You mentioned climate change. That's a concern, and u have proposed businesses to address it, but I disagree with the current Canadian government's strategy. They just created a new tax. A tax paid by average working people. We have too much tax now, and if you look at history since World War 1 there's been steady increase in tax. Paul Martin reduced tax, but all other politicians have been fighting against that, increasing tax.

Climate change is complicated. One issue is activists have become a cult, and anyone who disagrees with their doctrine is accused of being a denier. They claim science is on their side but when you show the propaganda they're spewing to actually scientists they strenuously disagree. Activists obsess over the rapid global warming that happened in the last 3 decades of the 20th century but don't want to face the 115 years of manmade global cooling that came before. If they did, they would have to admit the global warming was the planet recovering from the global cooling. As of the end of 1998 the planet's temperature was equal to what it was supposed to be at that time. And global warming almost stopped at that point. Global warming today is a tiny bit above the pace of nature, but not much.

There is some left, we do need to address it, but we certainly cannot justify destroying the economy. Activists want to go cold-turkey on oil and natural gas. They obstruct construction of any new pipelines.

The government tried to play both sides but hasn't done a good job.

Yes we have to address the issue. CO2 rose from 407 ppm in April 2019 to 415 in September 2020. But tax is not the solution. A Canadian Conservative posted a graphic on Facebook listing the number of trees in Canada and the number required to remove all the CO2 that Canada emits. I could look it up but conclusion is about 99% of trees are "unemployed".

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