Mars Colonization Discussion Thread

[Diche Bach]

On 11/6/2017 at 3:06 AM, Green Baron said:

Who said one can grow potatoes in Marsian soil ? :-)

It must be refined before it can be used. Techniques would have to be developed. One would surely have to separate the growing grounds from the natural soil to avoid contamination. A real life Whatney would have died.

https://www.nasa.gov/feature/can-plants-grow-with-mars-soil

https://www.nature.com/articles/s41598-017-04910-3

Otoh it seems unlikely that bacteria on the outside of the landers might survive. Is that good news ?

 

The whole Mars colony thing is pretty premature.

Quote

Here is what astronauts are doing with plants on the International Space Station today.

Hey! I'm glad they are doing SOMETHING up there with PLANTS and not just playing guitar and sight seeing, given that . . . you know . . . people gotta eat and stuff like that.

I keep wondering: has the first child already been conceived up there and no body is telling cause they don't want to breach some kind of NASA ethics codes? Wonder if giving birth in micro-gee would be easier or harder . . .

[tater]

5 minutes ago, Diche Bach said:

Hey! I'm glad they are doing SOMETHING up there with PLANTS and not just playing guitar and sight seeing, given that . . . you know . . . people gotta eat and stuff like that.

I read recently that of the 6 crew, 5 man-days per day are spent on maintaining ISS. 1 man-day of labor is "science." As a result, flying a single extra crew member would literally double the science work done.

This should also inform people about how easy long term life support actually is... (not easy at all)

[Diche Bach]

Tater, in a previous post you said something about an "MAV" landing ahead of the actual mission by several months "enough to make propellant . . ." or something along those lines.

Is this a serious idea? Land a robotic craft, that will "make chemical rocket propellant/fuel?" How exactly does that work?

So could this thing just "land" in the middle of the Gobi desert or the rocky part of Antarctica and "make fuel!?" Neat!

Edited November 7, 2017 by Diche Bach

[tater]

That’s Zubrin’s idea (*I think), that NASA adopted a long time ago. Bring some extra hydrogen in some versions, and make methane propellant from CO₂.

https://www.nasa.gov/pdf/373665main_NASA-SP-2009-566.pdf

The idea is that the crew land in a habitat vehicle, but leave in the Mars Ascent Vehicle. That one is sent ahead, such that if it isn’t refueling/refueled, the crew doesn’t land. NASA is all about abort modes.

Edited November 7, 2017 by tater

[DerekL1963]

29 minutes ago, tater said:

I read recently that of the 6 crew, 5 man-days per day are spent on maintaining ISS. 1 man-day of labor is "science." As a result, flying a single extra crew member would literally double the science work done.

This should also inform people about how easy long term life support actually is... (not easy at all)

"Maintaining the station" != "life support".  The latter is certainly a subset of the former, but it's emphatically not the whole of the former.   And without knowing how those man-days of maintenance are spent, it's hard to extrapolate to a Mars vehicle.  (A Mars vehicle won't have parts that are decades old for example.)

[Diche Bach]

16 minutes ago, tater said:

That’s Zubrin’s idea, that NASA adopted a long time ago. Bring some extra hydrogen in some versions, and make methane propellant from CO2.

https://www.nasa.gov/pdf/373665main_NASA-SP-2009-566.pdf

The idea is that the crew land in a habitat vehicle, but leave in the Mars Ascent Vehicle. That is sent ahead, such that if it isn’t refueling, the crew doesn’t land.

Hmmm. I did a quick search on methane in that PDF and I see them talking about it but science babble is often worse than legal babble.

So are we talking about: a lander that sucks up Martian atmosphere, separates it and poops out methane and Lox into tanks? Are there machines that can do that in methane rich environments back on Earth and which occupy the same amount of volume/mass/power consumption as whatever hypothetical they are referring to? Is this just a "concept" paper ("well . . . we could do it this way . . .") or are there actual machines that can accomplish these tasks in comparably harsh environments on Earth where the atmospheric conditions are suitable (say in a lab)?

ADDIT: actually a very interesting article thanks for posting that. Skimmed over the sections 3.4 and 4: white paper published in 2009 (12 years ago) and they were looking at (not planning, just looking at) launch windows in the 2035 ball park. Cargo mission departs 2035. Crew mission departs 2037. Crew arrives back at Earth 2040.

I wonder if conception, design, planning, building and preparation are in fact 12 years along from this apparently purely conceptual paper in 2009 or if the actual "possible, maybe" window we'd be looking at now if they repeated that paper would be more like . . . Cargo mission departs 2043. Crew mission departs 2045. Crew arrives back at Earth 2048.

I'll be 80 by that point, so I should have finished a few Marathons and leveraged my first few billions into trillions, so maybe they'll let me hitch my RV to one of the Cargo missions and tag along!?

Edited November 7, 2017 by Diche Bach

[tater]

52 minutes ago, DerekL1963 said:

"Maintaining the station" != "life support".  The latter is certainly a subset of the former, but it's emphatically not the whole of the former.   And without knowing how those man-days of maintenance are spent, it's hard to extrapolate to a Mars vehicle.  (A Mars vehicle won't have parts that are decades old for example.)

Certainly true, but a decent % of such repairs should relate to the basic function of station I’d think, the only other maintainence would be what, broken down science equipment? Seems like there isn’t too much up there that is frivolous, right?

The MIT guys who debunked Mars One used stats from ISS repairs on critical hardware to show that such a colony effort needed more spare parts mass than anything else as I recall (admittedly they need to ship 2+ years worth at a time).

[PB666]

1 hour ago, tater said:

Certainly true, but a decent % of such repairs should relate to the basic function of station I’d think, the only other maintainence would be what, broken down science equipment? Seems like there isn’t too much up there that is frivolous, right?

The MIT guys who debunked Mars One used stats from ISS repairs on critical hardware to show that such a colony effort needed more spare parts mass than anything else as I recall (admittedly they need to ship 2+ years worth at a time).

That's what I was thinking, and wait until you get into ISRU, drilling holes, repairing EVA suits,  Repairing robots, cleaning solar panels. Basically anyone who stays are Mars for a year will be performing diaper duty of robotized equipment they need for life support.

The thing about light weight equipment, its often not the most durable version of whatever device it is. The Apollo lander was called a rattletrap during its testing flights.

[tater]

Yeah ^^^ that brings it on topic to colonization. Another aspect is how to have many people on eva, and keeping things clean. Here in NM, dust gets into everything, causing wear on moving parts, for example. 

[DerekL1963]

1 hour ago, tater said:

Certainly true, but a decent % of such repairs should relate to the basic function of station I’d think, the only other maintainence would be what, broken down science equipment? Seems like there isn’t too much up there that is frivolous, right?

"Maintenance" != "repairs".  It also refers to preventative and periodic maintenance.  For example, I performed corrective maintenance (repairs) to restore suction on our vacuum cleaner this last weekend by tightening a loose internal hose connection...  but since I had it apart anyhow I also performed my periodic maintenance and cleaned the filters.  My preventative maintenance on my car (oil change) isn't due for another 4,000 miles. 

And  that's all assuming that "maintaining the station" (to quote you quoting your source) means only "maintenance" and doesn't include housekeeping and operating tasks.
 

1 hour ago, tater said:

The MIT guys who debunked Mars One used stats from ISS repairs on critical hardware to show that such a colony effort needed more spare parts mass than anything else as I recall (admittedly they need to ship 2+ years worth at a time).

Which isn't actually a problem so long as you have enough cargo capacity.  Or, to put it more clearly it's easy to misunderstand their point...  Which is that the problem with Mars One wasn't that it needed so many spares, (AIUI) it's that it had insufficient cargo capacity.

[tater]

2 hours ago, DerekL1963 said:

"Maintenance" != "repairs".  It also refers to preventative and periodic maintenance.  For example, I performed corrective maintenance (repairs) to restore suction on our vacuum cleaner this last weekend by tightening a loose internal hose connection...  but since I had it apart anyhow I also performed my periodic maintenance and cleaned the filters.  My preventative maintenance on my car (oil change) isn't due for another 4,000 miles. 

And  that's all assuming that "maintaining the station" (to quote you quoting your source) means only "maintenance" and doesn't include housekeeping and operating tasks.
 

I understand this, but I find it hard to imagine that such preventive maintenance:

1. is mostly on systems that are not necessary for human survival (seems like most everything interacts on station in such a way that it's at least semi-important, and yes, I'm not strictly talking about the "life support" systems like scrubbers, water recycling, etc).

2. 5 full time equivalent job positions 365 days a year? Seems unlikely for such a tiny space, it's about the volume of my house. To keep a staff of 5 busy all day, every day, they'd have to be remodeling (my house, not ISS  ) I think. 

I'm not saying you're wrong (the opposite), I'm just astonished that it could require that much constant attention to stay habitable/functional.

 

Quote

Which isn't actually a problem so long as you have enough cargo capacity.  Or, to put it more clearly it's easy to misunderstand their point...  Which is that the problem with Mars One wasn't that it needed so many spares, (AIUI) it's that it had insufficient cargo capacity.

Their point was that the spares would start to occupy a multiple of the crew launches proposed. 4 people, then 4X capsules full of parts. As a result, the costs skyrocket, and each new person adds to the required spares (more abuse of the systems). They based this on the % of spares flown on resupply missions as I recall (the video of their presentation at the Mars Society is online, but I watched it maybe last year).

I seem to recall the stuff about total crew time on non-science was WRT commercial crew, since they could then add another astronaut (7+ crew capability (total crew vehicles docked) for capsule allowing them to leave in an emergency). Can't find the reference.

 

Here's a NASA source:

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20160014540.pdf

Regarding ECLSS (TL;DR version, obviously very incomplete, and no numbers I could find on total man-hours):

“Current ISS experience with both U.S. and Russian ECLSS systems shows significant failure rates that would be unacceptable for an extended human exploration mission.”

"Substantial amounts of crew time are required for on-orbit maintenance"

"Significant crew time is required to maintain hardware that was not designed for on orbit repair"

Russell and Klaus state “total ECLSS maintenance for 865 days was found to exceed the design estimate by a factor of 22.”

 

 

 

 

On topic, that PDF shows how much work is needed on ECLSS for any Mars duration mission, much less habitation.

Edited November 8, 2017 by tater

[DerekL1963]

3 hours ago, tater said:

I understand this, but I find it hard to imagine that such preventive maintenance:

 Assuming that "five man days are required for maintaining the station" refers only to maintenance.  As I pointed out above, that's a shaky assumption.

Having served four years on a SSBN, I can easily understand how much maintenance might be required.  Especially given that the systems on ISS are a) essentially first generation, and b) almost certainly not well designed for maintenance.  (Submarines have been at it for over a century now, and we're still getting a handle on that.  It's a Very Hard problem when you're sharply space limited.)

 

3 hours ago, tater said:

5 full time equivalent job positions 365 days a year? Seems unlikely for such a tiny space, it's about the volume of my house. To keep a staff of 5 busy all day, every day, they'd have to be remodeling (my house, not ISS  ) I think.

Your house isn't even a fraction as complex as the ISS.   Extrapolating from one to the other is...  well, there's no single word in the english language expressing how ludicrous it it to even try.  Not to mention it's not particularly small, I've heard it quoted that it contains the same volume as the cabin of a 747 - which clocks in at 5k odd sq ft (or 460 m^2).  And that understates the matter, as ISS uses all four walls of a given space for equipment.

[DAL59]

14 hours ago, Diche Bach said:

So could this thing just "land" in the middle of the Gobi desert or the rocky part of Antarctica and "make fuel!?"

 

Yes.  It uses the sabatier reaction to process co2 into fuel.  

[tater]

The SSBN is a far better analog than my adobe house.

@DerekL1963 Question: how much non-critical hardware is there on a sub?

On station, if water vapor in electronics was a concern, then any hardware could be a fire hazard if not constantly checked. Not life support, but none the less related more to safety than just an experiment going belly up. Seems like in a closed environment, problems that would be minor in an office or house on Earth would be more concerning, right? Hence constantly checking stuff?

Edited November 8, 2017 by tater

[PB666]

There is one thing here I should mention. As long as we are talking about spare parts you don't have exactly the same problem as you do landing and taking off living people on Mars.

Landing small objects on Mars is alot easier than landing large objects. You could have a companion ship escort your travelers and parts shipments sent to the surface when need from LMO. Im not trying to minimize the problem but we really have to differentiate two problems.

Given an launch window, getting the physical human being to Mars is not a problem that much more complex than putting physical human beings in orbit about the moon. The work required to keep them alive is magnitude harder, but ISS is but a prototype survival unit, improvement have been made. Even so getting even one section of the ISS to the Mars surface is a monumental task. Getting it back in orbit is nearly impossible without better and more efficient engines.

So by definition we are going to initially be putting something small and manageable on Mars. This translates to extremely utilitarian structures. The next issue is how to do it. From a basic physics stand point if you want to put people on Mars and retrieve them, each person should go down as a single ship (one that can return to Orbit) but the ship itself would not be a habitat. So the habitat is something that could be assembled on dusty old mars (6000kg Per F9 launch with an ION Driven carrier but size would dictate a decent amount of fuel spent to land).

If we are assuming the landed station is built at a time before humanization, then its not a problem to stock pile parts . . . . . . A sealed dumpster on the outside of the habitat could hold parts. Again, since parts are not living and not food . . .you can send them up to Earth L2 have a circulator pick them up and wander to Mars L2 then detach the ship for Mars reentry and landing.

I have worked on some of the types of equipment that you might find on ISS. I have repaired a great many pieces of equipment. The largest piece I can recall was a power supply with about 12 different power feeds. It weighed about 15 lbs. Properly wrapped you could probably drop on Mars at 50 m/s and it would survive. These things are small you could drop them an inflatable heat shield over the target site and an airbag on landing, have one of those humans retrieve them. Most everything else are integrated circuit boards (which on many modern pieces means replace equipment).

If you are shipping fat to Mars you can simply embed a single wrapped circuit board in the oil and cool it to 4'C, its now protected. lol. Ship it in the food supply.
If you are shipping whole grains just put them in the bags of grain.

As per the dust issue. . . .I agree . . . . I keep making the argument that the settlements on Mars should be built into the Martian landscape, not on top of them. Its just another in a long list of reasons not to be on the surface. But unless we create much more autonomous mechanobots that are capable of mining Mars and also repairing themselves , the first habitats on Mars are likely to be surface habitats.

 

 

[PB666]

10 hours ago, DerekL1963 said:

 Assuming that "five man days are required for maintaining the station" refers only to maintenance.  As I pointed out above, that's a shaky assumption.

Having served four years on a SSBN, I can easily understand how much maintenance might be required.  Especially given that the systems on ISS are a) essentially first generation, and b) almost certainly not well designed for maintenance.  (Submarines have been at it for over a century now, and we're still getting a handle on that.  It's a Very Hard problem when you're sharply space limited.)

 

Your house isn't even a fraction as complex as the ISS.   Extrapolating from one to the other is...  well, there's no single word in the english language expressing how ludicrous it it to even try.  Not to mention it's not particularly small, I've heard it quoted that it contains the same volume as the cabin of a 747 - which clocks in at 5k odd sq ft (or 460 m^2).  And that understates the matter, as ISS uses all four walls of a given space for equipment.

The ISS could be larger, particularly now that its been moved to a higher orbit. This is the major difference between the ISS and what you place on Mars. If you are aerobraking down to the planet (Thrusting down can cost as much at 4500 dV), the size of something is very important. Friction is a function of surface area, but force is a function of mass, mass that exist in 3-dimensonal space. As you increase the size of a sphere with constant density the equilibrium velocity at any given air density is going to increase. So for instance if you double the volume the equilibrium velocity increases by 20 to 40% and so on.

The issue of size with the ISS, if we recall the complaints that have been repeated here ad-nausea in the past, was that the designated habitat launch vehicle was the STS. The STS has a limit on size given its cargo bay. It is not necessary a limitation on weight, but exterior volume only. Overtime the space shuttle was equipped to launch even more mass and could have launched habitats even double the weight (41% larger diameter) BUT could never launch structures of larger diameter. As a consequence the Shuttle is what determined the form-factor of the space station. Today there are many options, including ION driven systems to help station the ISS. With more efficient launch vehicles there is no problem getting humans or supplies to much higher orbits than previously desired.

We also forget that the STS is not the biggest or most payload worthy rocket that has been produced. THe primary problem with Payload Diameters is the aerodynamics below 30,000 meters. Part of this can be circumvented by launching and Alpine altitudes (also increase ISP) that establishes a Max Q at a higher altitude.

Does anyone want to see my space factory?

The design was supposed to have a sealable bay door but I could not work out a way to install it and animate it. I would have to alter the way docking ports work in the game.

This particular station runs on a 50MW capable fusion reactor (50T) (Top left, left of bell structure).  This particular (core is white part) design is not a single piece its made of 36 side/bottom pieces. The side pieces (constructed of 3 pieces, two of which are pressurized and have enterior structure capable of part manufactoring or assembly. The three veiwing decks in the Top right are added to the interior. These act as a final assembly area for larger parts and have a large door capable of individuals parts up to a meter in diameter. There are 3 docking ports close by as well as a downward facing 2+ meter docking port.

This particular was designed to be assembled in space starting with the central 12 sided central access facility with 12 closable doors a viewing area centered by a docking port (2+ meter diameter). The sides of each peice have a rubber gasket and act as a second line of defense against leaks. They are strung together loosely in space and then in a predesignated compartment the bindings are contracted drawing the vessels together once drawn each peice is bolted to the next from inside the pressure vessel using pressure tight mechanism. The End pieces are bolted from the outside together since they lack a pressure compartment. Because of the size of the vehicle and its shape if can be spun to provide a non-inertial environment for crew. When the End plate door is shut the viewing deck is virtually free of cosmic radiation due to the number and thickness of 3 walls.

The point I am making is that the ISS was not designed to be a space factory but an STS resourced science station. As such its function dictated its design. As space factory that has a much larger interior volume requirement would demand a much different assembly tactic.

Note: While I have not yet lifted the whole launch from RSS, I have orbited the entire factory from the surface of Kerbin (you have to zero gravity on the launch pad until you get lift off other wise . . . ).  THere is a smaller version of this that can be launched from Earth and could be used to assemble the parts for this factory. 

 

 

[DAL59]

8 hours ago, tater said:

On station, if water vapor in electronics was a concern, then any hardware could be a fire hazard if not constantly checked. Not life support, but none the less related more to safety than just an experiment going belly up. Seems like in a closed environment, problems that would be minor in an office or house on Earth would be more concerning, right? Hence constantly checking stuff?

These are all perfectly valid concerns about life support in space, but the ISS has already proved that CCLS for 6 months in space is possible.  

[tater]

Just now, DAL59 said:

These are all perfectly valid concerns about life support in space, but the ISS has already proved that CCLS for 6 months in space is possible.  

NASA itself says that LS needs to be made far, far nbetter for a Mars mission than what they have at ISS.

[DAL59]

If its the same length of time(shorter actually, for the ITS), why?

[tater]

I posted a link up thread to a NASA pdf. It;s pages of them saying that ISS LS won't cut it for Mars. Too much maintenance, too many failures, etc, etc. Not ready for a crew who can't hop into Soyuz and come home at no notice.

[DAL59]

After over a decade of operation, that has never happened though.  The ITs also has higher mass budget for redundancy.

[KSK]

Question about ISS maintenance. I'm wondering how much of the maintenance time is spent tightening the bolts (so to speak) and how much of it is spent planning exactly which order to turn the bolts in,  what happens if one of them flies off unexpectedly etc. etc. ? Might that explain some of the person hours required?

[tater]

50 minutes ago, DAL59 said:

After over a decade of operation, that has never happened though.  The ITs also has higher mass budget for redundancy.

What has never happened? They’ve had constant issues that need addressing.

Their repair model is usually to swap out subassembly parts, shipped up on resupply flights. Not an option for mars.

Redndancy takes on a new meaning when you are 2 years from home.

[DAL59]

23 minutes ago, tater said:

What has never happened?

They've never had to jump onto the soyuz and evacuate.

[tater]

28 minutes ago, DAL59 said:

They've never had to jump onto the soyuz and evacuate.

True, but that's an option they have.

Colonization means that they need to cover all their bases ahead of time.