Survival on Mars: Radiation & Temperature Challenges

[Bernie G]

... a SMALL number of people supplied for an indefinite perior (at enormous cost). We do not know how to get there safely. We do not know where we could establish a habitat safely. And we don't have even a guesstimate on the order of magnitude of the cost of getting anyone back. We do NOT have the technology for fusion power, ion drives, establishing eco-systems on Mars, or establishing a rudimentary manufacturing base on Mars...

Realistic talk.

 

[1oldman2]

I suspect you would receive a large amount of qualified volunteers.

Where do I sign up please ?

 

[GTOM]

Interesting.

http://www.reuters.com/article/us-space-mars-climate-idUSKCN0YH29N

I wondered about a few things. Could any lifeform on Earth withstand martian conditions, with minimal care (rad protection, or collect some water)? Could gene engineering help somehow? Would it make sense, that the streets of a colony is covered by lead glass usually, but shuttered during a solar storm, when radiation level peaks?

 

[enorbet]

The problems listed here for a manned Mars mission seem to be of 3 types
1) Getting there safely
2) Once there, surviving long enough and well enough to do good Science (or why go?)
3) Returning.

Getting there safely depends on sub-issues such as the number one issue, the definition of "safely". It seems to me that with the possible exception of radiation protection, most issues are within a decade of resolution. NASA is already backing a number of propulsion systems that can vastly increase safety by simply reducing elapsed time. Electric, Fission and Fusion are in the works and while a practical fusion drive might be achievable within a decade, fission drives with good power to weight ratios have already been built and tested. A finished product has high odds for success given a decade and the money to develop it The biggest problem there is Public Opinion, not an inconsiderable obstacle, but at least possible. Reducing trip time to roughly 90 days makes huge difficulties either diminish substantially or just go away altogether.

Returning is a much greater issue since there exists no infrastructure on Mars for liftoff from Mars and the concept of sending a parallel mission to provide even the lesser amount of capability for Mars gravity adds great, possibly near insurmountable, complexity and cost. Possibly the best solution for this is not planning for return at all or within the foreseeable future. This isn't completely unreasonable since more than 200,000 people applied for Mars One and most of those understood they may not return. More than a few have asked themselves "What if it is certain I will not return?" and they still applied. For reference see

Still even if we say those two are essentially solved, the remaining problem is still extremely daunting. The difficulty of just supplying basic needs (medical, food, shelter and oxygen) are massive obstacles requiring a huge amount of cost and effort to overcome, even if we assume and accept it is basically a "suicide mission". There is little point in going if it is impossible to get a return on investment, beyond the personal one of "immortality in the history books". Additionally, that "immortality" would certainly include considerable negativity associated with a "suicide mission" without a substantial return... more than just historical. Who wants to be remembered as a murderer?

If we don't assume return, then nothing physical can be harvested so that leaves only information, scientific information to be gained. This requires Mars quality space suits, instrumentation, and the expertise to employ them (and good judgment) not to mention habitat. Although it seems the South Pole is likely to have the most readily available water ice, even the means to harvest that is unknown technology especially when one consider the weight of any digging and processing tools. However, a digging tool might be cost effective if it is also used to create safer habitat. I haven't seen many plans that involve underground habitat which seems would provide helpful radiation protection at no transit weight penalty, so possibly there are intrinsic problems there that I haven't considered.

Again even if we consider habitat, water and oxygen solved as above, it still leaves medical (both medicine and training beyond mere First Aid) and food. The average adult consumes 6 pounds of food per day. Multiply that by crew size, likely 3 or 4 (let's use 4) and we get 24 pounds of food per day. Even a piddling month stay means 720 pounds of food just for one month. This is not at all trivial even if we assume we have the means to provide decent nutrition without spoilage, and that is by no means a given.

So the bottom line it seems to me is - Yes It is within the realm of possibility to land 4 people on Mars within a decade but even to do just that and assuming they die within a day or two after "phoning home" with a few man/hours of actual Science as a payoff - just that involves huge commitment that I just don't see happening in that time frame. On one hand everything is easier after the first time but even if the crew are actually willing to die shortly after landing, who is willing to send them there for that little payoff on a guaranteed suicide mission?

My guesstimate is 30-40 years given the current level of commitment to advancing space exploration will make many of current difficulties a LOT better odds. I hate to say that since I probably won't be around to cheer and enjoy the data stream, but we are talking reality, right?

 

[mfb]

but we are talking reality, right?

Then more realism would help.

and while a practical fusion drive might be achievable within a decade

No way. We would need a demo on Earth already to have one flying to Mars in 10 years. A spacecraft -sized fusion reactor? We don't have any device that provides surplus energy. Larger ones (as tested on Earth) are easier to make effective and they still didn't achieve a net surplus yet. ITER should do it, but only in more than 10 years, it won't make electricity out of it, it won't have a closed tritium cycle and it is way too large.

fission drives with good power to weight ratios have already been built and tested.

Fission reactors yes, fission drives no, and even the reactors not on a scale where you could use it for propulsion of a manned spacecraft .

We also don't have a spacecraft that can serve as living habitat for 3 months or more. We don't have a rocket that can lift such a spacecraft to space, and we don't have a rocket stage that can do the trans-mars injection.

Possibly the best solution for this is not planning for return at all or within the foreseeable future.

No space agency will send anyone on a planned suicide mission. If you don't want the astronauts to return, you have to plan to provide food, water and so on for decades. Unless you want to start colonizing, that is way more expensive and requires more cargo than landing a Mars ascent stage on Mars.

This isn't completely unreasonable since more than 200,000 people applied for Mars One and most of those understood they may not return.

And how many of them understand some basic science? And if that number is not small enough already, how many have the required knowledge to survive on Mars?

 

[CalcNerd]

No space agency will send anyone on a planned suicide mission. If you don't want the astronauts to return, you have to plan to provide food, water and so on for decades. Unless you want to start colonizing, that is way more expensive and requires more cargo than landing a Mars ascent stage on Mars.

.
What if you select four astronauts that are in their 60's. And since weight is precious, you plan a 10 -15 year plan without any return plan. Yes, a suicide plan of sorts, but all of the astronauts die from natural causes (and yes, you will provide suicide pills too, can you imagine suffering through cancer, which could happen to someone of any age in a high radiation environment. However, THAT would not be public knowledge.). That is pretty much the only option that gets us to Mars in the next 20-30 years, unless we have a major breakthrough in rocket/booster/lift technologies.

 

[mfb]

And since weight is precious, you plan a 10 -15 year plan without any return plan.

Take the 3 kg per person and day from above, and that crew needs ~45-60 tons of food over 10-15 years. For that mass, you can launch a rocket with the astronauts back to orbit, and another one to Mars orbit for trans-Earth injection.

And that's not even considering that the crew will run into medical problems soon as they get older.

That is pretty much the only option that gets us to Mars in the next 20-30 years, unless we have a major breakthrough in rocket/booster/lift technologies.

While Elon Musk's plans won't happen in that timescale, he might have the technology within 20 years, and quite likely within 30 if nothing goes really wrong. The Falcon 9 first stages have an empty mass of ~25 tons, landing a rocket of that mass on Mars would be sufficient to get astronauts back to Mars orbit. The only major breakthrough is landing huge payloads on a surface and reusing the rocket - the first part has been demonstrated on Earth, the second will probably be demonstrated later this year or on early 2017. After that, it's just about scaling things up, and creating living habitats for a crew.

Radiation damage on the surface can be avoided by putting martian soil on top of the habitats.

 

[Drakkith]

What if you select four astronauts that are in their 60's.

ANY plan to send people on a one-way trip to Mars would be rejected by NASA and probably every single other space agency in the world.

 

[nikkkom]

No space agency will send anyone on a planned suicide mission. If you don't want the astronauts to return, you have to plan to provide food, water and so on for decades. Unless you want to start colonizing, ...

That's exactly what we want. Colonizing. (If you don't want to colonize, why bother with manned space exploration anyway?). And colonists, by definition, do not generally plan to ever return.

 

[Ryan_m_b]

A manned mission is a totally different beast to a research outpost which is a totally different beast to a colony.

A colony is going to need regular shipments of everything, declining as a local economy develops. Problem is the cost of that is likely to be astronomical, even spread out over a long period. You've got to ship thousands of people, countless tonnes of tools and equipment, supplies of food/medicine, stocks of plant and animal life etcetera.

 

[mfb]

That's exactly what we want. Colonizing. (If you don't want to colonize, why bother with manned space exploration anyway?). And colonists, by definition, do not generally plan to ever return.

Even if you want to colonize in the distant future, you won't start with a colony. You start with a research team exploring the surface and going back, their research results then can be used to plan a long-term manned base, which eventually might become the seed of a colony.

We have a permanent station at the South Pole today. But Amundsen didn't go to the South Pole to stay there: he went there, explored the area, and went back. Later, with better technology and with the earlier research results, we went there again and built a station where people live for months to 1-2 years now. Still not a colony - people always go back after a while.

 

[D H]

This isn't completely unreasonable since more than 200,000 people applied for Mars One and most of those understood they may not return.

There's a lot of hype about Mars One. That 200,000 figure is one of them. While 200,000 people indicated some level of interest, only 2000 to 4000 or so actually applied (i.e., they submitted a completed application form and paid an application fee that varied from $5 to $73, based on GDP per capita).

Who wants to be remembered as a murderer?

When people start dying is when they stop the feed from Mars One. It's good to remember that the primary goal of Mars One is to be a reality TV show.

There's another way to be a murderer with respect to Mars. What if there's some kind of life on Mars, and what if microbes carried by the machines we send to Mars kill it? This unknown question is why every vehicle sent to Mars is assembled in a sterile environment and is intentionally opened to vacuum and solar radiation on the trip to Mars. That can't happen if we send humans to Mars. Being remembered as a murderer is one thing. Having our species guilty of planetocide is quite another.

If you don't want to colonize, why bother with manned space exploration anyway?

Colonization is not why we send humans into space. It might be, eventually, but that eventuality is well into the future. We have sent and continue to send humans into space

1. To avoid war. The US and Soviet Union engaged in the race to the Moon because each side severely wanted to beat the other at something grand, and the grandest option of all (global thermonuclear war) was deemed a less preferable option. The International Space Station can cynically be viewed as yet another war avoidance mechanism.
   
2. To showcase humanity at its best. This is a better way to look at the ISS.
3. To learn and do things that might have a return on investment here on Earth. This economic argument is what drove colonization here on Earth. What is the economic benefit of sending a colony to Mars?
4. To learn what is needed to eventually send humans far into space, because we will eventually do so.

There are many other reasons.

To make colonization viable it needs to have some kind of return on investment. That payback might be financial (e.g., asteroid mining, but that too is well into the future), scientific (e.g., telescopes on the far side of the Moon), educational (e.g., the plethora of educational videos created by the astronauts and cosmonauts on the ISS that motivate kids to study science and technology). While a reality TV show about colonists dying on Mars might make for good entertainment for some, it does not qualify as a good reason to send people to Mars.

There are a number of people and organizations who are very concerned about the steadily declining number of people who have been beyond low Earth orbit (the Apollo astronauts are getting old and are a dying breed). The right thing to do in space to rectify this problem is something that pushes the boundaries a bit but is still economically sustainable. Just as the Apollo program was not economically sustainable, so would be sending people to Mars in the near future. Once accomplished, the program would be declared "mission accomplished!" -- and then shut down.

What could be economically sustainable would be to send people back to the Moon / the vicinity of the Moon, only this time to stay for longer than just a few days. This would not cost as much as Apollo did; we now know how to do it. There are a number of advantages of going to the Moon as opposed to Mars. It's cheaper (taxpayers want this). Telescopes on the far side of the Moon (ESA and the Lunar Planetary Institute want this). Bootstrapping asteroid mining (NASA and private space want this). A quick return home in the case of medical problems (astronauts and cosmonauts want this).

 

[WmReed]

Heh getting a straight answer to a simple question on the internet. So hard.

I await the answer myself.

 

[nikkkom]

A colony is going to need regular shipments of everything, declining as a local economy develops. Problem is the cost of that is likely to be astronomical, even spread out over a long period. You've got to ship thousands of people

No, you don't have to ship thousands of people. Exactly because of the cost, initial space colony is likely to be even smaller than historical terrestrial colonies. It can be just 4-6 people.

countless tonnes of tools and equipment

Be clever. Send tools to make tools and equipment.

supplies of food/medicine

Medicine yes, food no. Greenhouses, hens. In some 20 years from now, maybe a machine to grow meat tissue (muscles) artificially, instead of hens.

 

[DHF]

I don't think we have to worry about anyone from Mars One dying on camera. It is extremely unlikely that this organisation will ever get anything off the ground. The plans they have proposed and the budget they outlined are not even close to realistic. You don't even need to get into the technical difficulties, the Financial, logistical and political-social obstacles are more then enough to ground the project.

Considering their first launch window is 1.5 years away and they have yet to announce any official contracts to actually build anything yet, I think the very real scenario is that this is a money grab for Mars One.

 

[nikkkom]

There's another way to be a murderer with respect to Mars. What if there's some kind of life on Mars, and what if microbes carried by the machines we send to Mars kill it? This unknown question is why every vehicle sent to Mars is assembled in a sterile environment and is intentionally opened to vacuum and solar radiation on the trip to Mars. That can't happen if we send humans to Mars. Being remembered as a murderer is one thing. Having our species guilty of planetocide is quite another.

I heard this before. Bacteria have no rights. You kill millions every time you brush your teeth. Not landing people on Mars because they might exterminate Martian microbes is ridiculous.

Colonization is not why we send humans into space.

I am not aware of any official ruling why we send people to space. I disagree with your opinion why we do it.

 

[DHF]

No, you don't have to ship thousands of people. Exactly because of the cost, initial space colony is likely to be even smaller than historical terrestrial colonies. It can be just 4-6 people.
Be clever. Send tools to make tools and equipment.
Medicine yes, food no. Greenhouses, hens. In some 20 years from now, maybe a machine to grow meat tissue (muscles) artificially, instead of hens.

The big problem with setting up a colony on Mars is that it *would* take a staggering amount of resources to get it started, there is no real way to shoestring it. The biggest bottleneck is power. Things like building structures and 3D printers to fabricate tools and greenhouses all require power, far more power then a few solar panels can provide and just sending more panels isn't realistic either because panels and the batteries they charge would add mass to the launch and thus cost more. As others have pointed out here, Setting up a colony on Mars would only happen if there was a return on investment.

No Agency or Organisation is going to foot the bill to set up shop on Mars unless we discovered a massive underground deposit of unobtainum there.

 

[mfb]

Mars One was never realistic.

I heard this before. Bacteria have no rights. You kill millions every time you brush your teeth. Not landing people on Mars because they might exterminate Martian microbes is ridiculous.

You kill millions of them, but you don't wipe out the whole species, or even the full tree of life that evolved over billions of years (including us, in the case of Earth), also ruining the opportunity to learn much more about how life evolves.

The NASA rovers actively avoid the regions on Mars where life is the most likely - because they don't want to risk to introduce microbes from Earth there.

Colonization is not why we send humans into space.

I am not aware of any official ruling why we send people to space. I disagree with your opinion why we do it.

Everyone actually sending humans to space agrees with D H and disagrees with you. This will probably change once SpaceX sends humans to space.

 

[Ryan_m_b]

No, you don't have to ship thousands of people. Exactly because of the cost, initial space colony is likely to be even smaller than historical terrestrial colonies. It can be just 4-6 people.

You might start with 4-6 people (in which case you have a research outpost, not a colony) but 4-6 people does not a sustainable technoeconomy make. You will be needing to ship large quantities of people if you want that.

Be clever. Send tools to make tools and equipment.

Obviously! But simply saying "bring tools to build tools" is a far cry from the complex industry a colony would need to be economically self sufficient (or at least sufficient enough that Earth doesn't have to pay through the nose for constant shipments).

Medicine yes, food no. Greenhouses, hens. In some 20 years from now, maybe a machine to grow meat tissue (muscles) artificially, instead of hens.

And all the required technology, tools, material and all the support industries to sustain that closed-agriculture is going to have to come from somewhere and it isn't going to be Matt Damon on his todd with a spanner.

 

[CalcNerd]

Any space mission lasting more than a few years may ultimately be a death sentence to any astronaut thinking to return to earth. Muscles atrophy in space ie the heart too. Mars has less gravity to re-acclimate to, but the Earth after a 5 year absence? Sure, our current astronauts work out, but burning calories for exercise takes food. If you send 60 year old colonists (to placate the people who don't want to send these astronauts on one way missions), you save thousands of pounds as these colonists only have to maintain themselves for Martian gravity.
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If you can't accept the above plan, the first man on Mars will be 50-60 years away. And as the globe gets warmer and these types of projects skyrocket in cost, in 30-40 years you may not see it at all. The humongous amounts of energy to move anything from our orbit to ANY other orbit prohibits anything but a feeble 2 man attempt that is extremely risky for return or just accept the fact that once you touch down on Mars, you are stuck. It isn't the Moon with a low escape velocity.

 

[GTOM]

Just to be sure, i ask here too, how dangerous are the sandstorms?
According to wiki, the winds can start with 400 km/h on the poles, but they also said, that in the thin air, they arent really nasty.

Agriculture, theoretically, could the sun give enough light and heat to a greenhouse, that plants accustomed to cold areas of Earth could grow?

 

[Drakkith]

Just to be sure, i ask here too, how dangerous are the sandstorms?
According to wiki, the winds can start with 400 km/h on the poles, but they also said, that in the thin air, they arent really nasty.

Agriculture, theoretically, could the sun give enough light and heat to a greenhouse, that plants accustomed to cold areas of Earth could grow?

The mean surface pressure is only about 0.6% I believe, so a 400 km/h wind should feel more like 2 or 3 km/h. Particles in the air could pit and erode surfaces still, but you won't get blown over.

Light intensity is about half of that here on Earth, but I don't know how plants would react to the reduced light other than slower growth. I'm sure you could set up some big fresnel lenses or something to increase the amount of light if need be.

 

[mfb]

If you can't accept the above plan, the first man on Mars will be 50-60 years away.

Where is your study showing that a return mission cannot be done quicker - especially as several space agencies disagree with that statement? This is a science forum, not "I'm making up numbers and state them as fact"-forum.

and these types of projects skyrocket in cost

The cost to send stuff to space tends to go down.

The humongous amounts of energy to move anything from our orbit to ANY other orbit prohibits anything but a feeble 2 man attempt

Where is your study showing that?

 

[CalcNerd]

Guilty as charged on 1st and 2nd charge. The third statement about humongous amounts of energy is a FACT. You can crank THOSE numbers out yourself.
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1st, Mars is NOT the Moon. And until NASA or any other space agency assumes more risk, our current and foreseeable technology doesn't lend itself to getting us to Mars in 2030 or 2040 as the optimistic NASA propaganda implies. I believe NASA relies upon funding from a congress (often by former congressmen such as Newt Gingrich). These guys WANT results, not wasting money on 40-50 year plans (I am being sarcastic here, I actually don't believe there is much intelligence in either house). So if you want funding, do you tell them that, the hard truth? Or do you sell the soft shoe shuffle and put together a nice power point presentation for continued funding. Perhaps NASA will develop a remote lander, such as the Russians did for the Moon, but again, Mars is much more difficult to get off of than the tiny Moon. That may be possible in a decade or so ie 2030. Getting off of Mars and back to good ole Earth is going to take a rocket the size of a Saturn V. I don't envision that in the next 20 years.
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Physically, Man has a very hard time in space ie see data on our recent astronauts, living in the space station for extended periods of time ie a year or so. A Mars mission will be 3-4 years (ie admittedly with our current rocket technologies). But I don't see anything promising on the horizon to shorten THAT Trip. And if you want to blast your way to Mars with a faster plan, your energy requirements (fuel) go up and your payload goes down. I've heard talk of an Orion project being adapted, but that requires nuclear propulsion that will likely never be approved, at least for a Mars program anyway.
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You can sell me on Moon bases and all sorts of Moon related ideas. Mars, I'm going to be a skeptic.
.

 

[mfb]

The third statement about humongous amounts of energy is a FACT.

That's is not the critical point. Your claim that this would prevent crew sizes larger than 2 is the unsourced claim. We know rockets can lift crews of 7 to orbit from Earth - with a much higher escape velocity than Mars.
On Mars you need a bigger rocket than the Apollo ascent stage, sure. So what? We didn't discuss costs so far.

I believe

Science doesn't work based on beliefs.
There are also independent reviews of NASA plans.

Getting off of Mars and back to good ole Earth is going to take a rocket the size of a Saturn V.

The SLS, currently in development, is planned to get bigger than the Saturn V. You can also do in-orbit docking with two launches if you need a factor 2 in mass.

 

[enorbet]

Then more realism would help.

I think you and many others "missed the gist". Did you not notice how many REALLY liberal "givens" there were? My point actually was that even if we assume some real show-stoppers can be overcome in 10 years, the basics of food and shelter currently and for a lot longer than 10 years bring it all to a screeching halt. I really hate having to come to such a negative conclusion but that's where the data leads me.

No way. We would need a demo on Earth already to have one flying to Mars in 10 years. A spacecraft -sized fusion reactor? We don't have any device that provides surplus energy. Larger ones (as tested on Earth) are easier to make effective and they still didn't achieve a net surplus yet. ITER should do it, but only in more than 10 years, it won't make electricity out of it, it won't have a closed tritium cycle and it is way too large.

The fusion propulsion in 10 years is admittedly one of my really liberal givens, partly justified I think in that it is not the only improvement on chemical propulsion upon which we are working with no theoretical "no can do" yet.

Fission reactors yes, fission drives no, and even the reactors not on a scale where you could use it for propulsion of a manned spacecraft .

Here I beg to differ if only slightly unless I am interpreting the confirmed results with too much fervor.

[qupte=wikipedia-NERVA]
NERVA XE
The second NERVA engine, the NERVA XE, was designed to come as close as possible to a complete flight system, even to the point of using a flight-design turbopump. Components that would not affect system performance were allowed to be selected from what was available at Jackass Flats, Nevada to save money and time, and a radiation shield was added to protect external components. The engine was reoriented to fire downward into a reduced-pressure compartment to partially simulate firing in a vacuum.

The NERVA NRX/EST engine test objectives now included:

1. Demonstrating engine system operational feasibility
2. Showing that no enabling technology issues remained as a barrier to flight engine development.
3. Demonstrating completely automatic engine startup.

The objectives also included testing the use of the new facility at Jackass Flats for flight engine qualification and acceptance. Total run time was 115 minutes, including 28 starts. NASA and SNPO felt that the test "confirmed that a nuclear rocket engine was suitable for space flight application and was able to operate at a specific impulse twice that of chemical rocket system [sic]."[1] The engine was deemed adequate for Mars missions being planned by NASA. The facility was also deemed adequate for flight qualification and acceptance of rocket engines from the two contractors.
[/quote]

Note: Bold within the quote is mine.

So is your argument that even if we really were willing to put the money into it, 10 years is still too short a time to go from NERVA XE to a working mars-ready engine? Considering how much didn't even remotely exist when JFK issued the "Moon Landing Imperative", even given the order of magnitude difference in problems due to distance, in't this commitment like most commitments that "if you wait till you can afford it, you'll never do it" ?

We also don't have a spacecraft that can serve as living habitat for 3 months or more. We don't have a rocket that can lift such a spacecraft to space, and we don't have a rocket stage that can do the trans-mars injection.

Could you outline the problems that are show-stoppers for a 3 month habitat craft in 10 years? With the reduced exposure time to radiation I think this could be doable in 10 years, again, given the funding. If NERVA NRX/EST 202 is a possibility the 2nd issue is doable. The 3rd issue of mars-injection is a considerably "stickier wicket". So that could be the end of discussion right there, at least for a 10 year time frame.

No space agency will send anyone on a planned suicide mission. If you don't want the astronauts to return, you have to plan to provide food, water and so on for decades. Unless you want to start colonizing, that is way more expensive and requires more cargo than landing a Mars ascent stage on Mars.And how many of them understand some basic science? And if that number is not small enough already, how many have the required knowledge to survive on Mars?

This is the deal-breaker I am talking about - Food and Shelter since despite the number willing to go and die there and even IF some few were actually qualified, nobody is going to plan a suicide mission in any sort of serious proposal and we simply do not have the means now and for a very long time to house and feed a long term stay and shuttling supplies is a huge increase in cost and risk.

FWIW - Colonization? No way! I can't see an actually serious attempt at colonization for anything under 100 years, maybe more. The bottom line is that it is just too expensive to achieve all the breakthrough technology needed for colonization in 100 years, or a manned mission in 10. I wish it weren't so but then "if wishes were Ferrarris..." While a few may be within reasonable reach, the ones that are not, and there are several, are just beyond budget AND foreseeable technology within any timeframe under 20 years, just for a manned visit-and-return mission.

PS Please forgive my lapse of recall on quoting wikipedia protocol. I will attempt to rectify that within 24 hours. Hopefully it isn't too confusing as is even if improvement is rather needed. I should have been asleep hours ago. For now I will "bold" the quote commands.

 

[mfb]

I said fission drives have never been used (in space). A ground test puts it at TRL 5 or 6 depending on how the test worked. It might be possible to build one in 10 years, but that would need significant effort, and putting a lot of fissionable material in space is problematic in terms of politics.

Could you outline the problems that are show-stoppers for a 3 month habitat craft in 10 years?

That part is probably not so challenging (we have ISS modules as prototypes), but it adds to the costs.

If NERVA NRX/EST 202 is a possibility the 2nd issue is doable.

NERVA with the specifications from the Wikipedia page could not launch itself from the ground - 180 tons mass full, but only 35 tons*g thrust. We don't have a rocket that can lift 180 tons. The heaviest existing one gets 23 tons to low Earth orbit, that is not even sufficient for the empty NERVA reactor at 34 tons. Four Falcon Heavy launches might work.

 

[Ryan_m_b]

NERVA with the specifications from the Wikipedia page could not launch itself from the ground - 180 tons mass full, but only 35 tons*g thrust. We don't have a rocket that can lift 180 tons. The heaviest existing one gets 23 tons to low Earth orbit, that is not even sufficient for the empty NERVA reactor at 34 tons. Four Falcon Heavy launches might work.

Would I be right in thinking that those four flights would also add to complexity given that the reactor/rocket would have to then be assembled in space? If a nuclear rocket can't be easily designed in a modular way and instead needs proper assembly that would seem to massively add to the cost by requiring more tools, specialists, possibly infrastructure and time.

 

[nikkkom]

You might start with 4-6 people (in which case you have a research outpost, not a colony) but 4-6 people does not a sustainable technoeconomy make. You will be needing to ship large quantities of people if you want that.

A colony does not start completely self-sufficient.

Colony differs from research outpost by having a different goal. A research outpost focuses on science (and scientists don't plan to stay there forever, they plan to go back), colony focuses on establishing a new place to live, on increasing its self-sufficiency.

simply saying "bring tools to build tools" is a far cry from the complex industry a colony would need to be economically self sufficient (or at least sufficient enough that Earth doesn't have to pay through the nose for constant shipments).

Let's see what a colony need to survive, and what of those items must be shipped from Earth.

Oxygen? Mars has it.
Water? Check.
Power? Solar works. If more is desired, a small nuclear power reactor needs to be shipped once in some 50 years, not every year. Technology exists (submarine reactors).
Food? Can be produced locally, although much research is needed, and initially (while R&D is ongoing) it has to be shipped from Earth. Likely dehydrated.

Tools? 3D printers must be shipped from Earth, initial compliments of machining tools too must be shipped from Earth. Likely a miniaturised (as much as possible, still heavy) steelmaking plant. And/or aluminium plant. And/or rock processing plant (basalt fibers, bricks, etc).
When that is operational, a lot of heavy equipment (for example, earthmoving equipment) can be made locally. Same for construction materials.

Medicine? Must be shipped from Earth, but it's not very massive.

Batteries? Computers, radios, cameras, other semiconductor-based devices? Must be shipped from Earth.

So yes, a significant resupply will have to be sustained. But the most massive and continuous needs such as air, water, food, and basic construction materials don't need to be sent. All heavy items need to be sent only occasionally (reactor, aluminium plant,...), they are not consumables.

A "stupid" approach of just sending everything in ready-made form, including food and construction materials, is clearly not workable. If this thing wants to be a colony, it needs to work towards being a colony. Not a research outpost.

 

[nikkkom]

FWIW - Colonization? No way! I can't see an actually serious attempt at colonization for anything under 100 years, maybe more. The bottom line is that it is just too expensive to achieve all the breakthrough technology needed for colonization in 100 years

Can you list all the breakthrough technology we need to build a Mars colony, and don't yet have?

 

[GTOM]

Can you list all the breakthrough technology we need to build a Mars colony, and don't yet have?

Well i think a nuclear propelled ship wouldn't hurt.
I wondered, could it serve as an orbital power plant, and beam down power to recharge batteries?

 

[nikkkom]

Well i think a nuclear propelled ship wouldn't hurt.

"Wouldn't hurt" is not the same as "must have". Do we "must have" a nuclear propelled ship? I don't think so.

 

[GTOM]

Let's see what a colony need to survive, and what of those items must be shipped from Earth.

Oxygen? Mars has it.
Water? Check.
Power? Solar works. If more is desired, a small nuclear power reactor needs to be shipped once in some 50 years, not every year. Technology exists (submarine reactors).
Food? Can be produced locally, although much research is needed, and initially (while R&D is ongoing) it has to be shipped from Earth. Likely dehydrated.

How much water can be acquired outside the poles? If we have to land on the poles, i think we need to start with nuclear power, so with a nuclear propelled ship.

 

[nikkkom]

How much water can be acquired outside the poles?

People on forum.nasaspaceflight.com discuss all Mars colonization-related topics a lot. Including this one. There was a post where it was estimated water on Mars can even be extracted in sufficient quantities from atmospheric water vapor.

This needs processing of a lot of air, OTOH it eliminates the need to dig the icy regolith and shovel it around. The latter probably can't be done without humans constantly controlling the process.

 

[nikkkom]

Here are links to some discussions on NSF:

http://forum.nasaspaceflight.com/index.php?board=21.0
"Missions To Mars" subforum

http://forum.nasaspaceflight.com/index.php?topic=40178.0
The Mars settlement / Martian homesteading narrative 2 (Read 19865 times)

http://forum.nasaspaceflight.com/index.php?topic=40521.0
Offworld egg production: an analysis (Read 2910 times)

http://forum.nasaspaceflight.com/index.php?topic=40308.0
Water, Methane, and Oxygen ISRU on Mars (Read 1532 times)

http://forum.nasaspaceflight.com/index.php?topic=40555.0
Radiation mitigation strategies for early SpaceX Mars missions (Read 8812 times)

http://forum.nasaspaceflight.com/index.php?topic=40485.0
James Logan, MD. living on Mars. Opinions on his conclusions. (Read 8888 times)

http://forum.nasaspaceflight.com/index.php?topic=40496.0
When you can land anywhere on Mars where’s the best place? (Read 4229 times)

http://forum.nasaspaceflight.com/index.php?topic=40508.0
Interplanetary commerce - Earth<=>Mars if SpaceX succeeds (Read 3179 times)

http://forum.nasaspaceflight.com/index.php?topic=35877.0
Scaling Agriculture on Mars (Read 57504 times)