B Survival on Mars: Radiation & Temperature Challenges

[enorbet]

I don't think there is anything that humans have that is fundamentally irreproducible with technology.

The alternative would be Vitalism.

It seems you have taken the point of view of the theoretical, the "in principle", as opposed to my view of the practical and efficient. I'm not claiming there is some fundamental difference between what we consider to be alive and what doesn't fit our limited definition of Life. I'm saying that it is entirely impractical to program a computer exactly in the manner that humans are programmed and that each has it's advantages and drawbacks.

Additionally, and possibly for another thread in another section, is the fact that there is a fundamental difference in computational methodology in that, so far, computers are strictly limited by design to function in binary and that we don't know yet exactly how the human brain functions, not even what consciousness is and why there was apparently an evolutionary advantage to it. While theoretically it may be possible that a computer can achieve consciousness, it is not yet an accomplished fact nor do we know if that would be a net gain, at the very least to humans. It is also not known if human lifetime's worth of slow, largely uncontrolled programming would be of any benefit to a binary brain(s). We also can't discount that there exists billions of humans, each with different sets of programming who can communicate and learn from each other in a manner that is very different from mere data sharing.

As for the "when?" and "at what cost?" that we may get some answers in the coming decades is interesting for certain but since these important questions are unanswerable today I submit it is impractical to rely on that hope instead of using what we now do know. We know that Man can survive for some time in Space and on another world and that humans bring something to the table that machines cannot currently duplicate and while it is presently deemed too costly to extend that to Survival On Mars, that is a matter of economics and the assumption that our money is better spent elsewhere.

Absolutely no possibility? Do you really think you know it better than the experts looking into exactly this?

"This" being autonomous computers... presumably able to alter their own programming and that of other computers? With sincere respect I must ask, "What experts?" Since such computers don't yet exist and nobody fully understands how a human brain functions (as noted above), how can anyone be a true expert other than "in theory" and in this case "theory" is much more like "hypothesis" since there is extremely little relevant test data as nothing yet exists upon which to apply testing.

Plus, again with the practical, just how long do you suppose it will be before there can be any agreement to allow not one, but many computers to actually learn from and reprogram each other in any human-like, autonomous manner and possibly to build others even more powerful? It may well come to pass but I strongly suspect it will be quite far in the future and fought "tooth and nail" the whole way just as Elon Musk, Stephen Hawking, and other influential, expert people are already engaged in "putting the brakes on" such a proposal. If you think public outcry altering NASA's plans from a few deaths was to be expected (and possibly justified), just wait till there is even one death remotely connected to self-programming, autonomous computers occurs. One doesn't have to be an expert at anything to calculate how that movie ends, even if only for a time.

It seems we have some fundamental disagreement and I'm not at all sure why. Are you categorically opposed to humans in Space? not recognize the value of a tight team of both? or just basically believe that machines are superior, or soon enough will be, in every way?

 

[GTOM]

I thought a bit about the human vs computer issue (i write my current thoughts here, if the topic continues, create another thread)
So in case of a present day neural network emulation program, we don't know how exactly they react in unforeseen situations, most likely they fail (i saw the gif, robodog meets banane on the floor) but we can be sure, they will never came to such conclusions, that self driving car throws out its passangers to help its survival.
But if they can react to unknown situations, connect far away things like humans do, they can come up with such conclusions. It might be helped by a supervisor code like Asimov's laws, but a strong AI can still circumvent them, but my passangers weren't humans, they were experimental dolls.
So, if we want to have programs that can be more human like, we have to be prepared to assume, they will be unpredictable, and we expect the opposite from machines.

So while i don't say, that "true" AIs are theoretically impossible (i have doubts that they could be fitted into an android body rather than a large server room) but i definitally wouldn't want to use them to explore unchecked by humans on the site.

Of course it perfectly makes sense to use low level AIs to explore a really good site and construct a base before humans reach Mars.

 

[Chronos]

Point well taken. It appears we are all in basic agreement..

 

[mfb]

It seems you have taken the point of view of the theoretical, the "in principle"

I had this view the whole time and expressed this multiple times (e.g. with "fundamentally irreproducible"). That is the only level where we can make clear predictions.

computers are strictly limited by design to function in binary

You can simulate non-binary systems with binary systems, if necessary.
There is no need for consciousness, that is an ill-defined concept anyway.

We currently do not have robots that perform human-like research tasks on Mars, but we currently also do not have humans on Mars. Both could be viable in the future, so both options should be investigated.

"This" being autonomous computers... presumably able to alter their own programming and that of other computers? With sincere respect I must ask, "What experts?" Since such computers don't yet exist and nobody fully understands how a human brain functions (as noted above), how can anyone be a true expert other than "in theory" and in this case "theory" is much more like "hypothesis" since there is extremely little relevant test data as nothing yet exists upon which to apply testing.

There are AI experts in the same way as there are experts working on systems that can bring humans to Mars.

There is no need to make the AI truly human-like to make it better at exploring Mars. Just better in performing research is sufficient.

I'm not opposed to humans in space, and I support the efforts to plan a manned mission to Mars, I don't see how you got the opposite impression. I just don't see where you get the confidence from to say that robotic missions will never be able to do tasks humans can do.

 

[enorbet]

Thank you, mfb, I see your position much more clearly now and find we aren't as far apart as I once concluded. My point is quite small and not projected far into the future, being reduced to current exploration of Mars and the fairly immediate future. We apparently do agree that there is some fundamental difference between humans and machines, whether we conclude it is from the difference in how they are programmed or how they compute. There is currently also a difference in the size and mass relative to adaptive computational power. If there was no difference, there would be far less reason to even consider sending humans... at least until machines and humans have progressed to the point that machines have achieved and been granted the value afforded to things "Alive". So my point has been simply that I think it would be wise to include more research into what is needed to provide a relatively safe human environment in Mars exploration, rather than what appears to me to be more like exclusive substitution.

As for my confidence I didn't say nor do I subscribe to "never", especially "in principle'. My point was simply one of practicality. I can't escape that I majored in Engineering not Theoretical Physics or Computer Science. Short of "never" I don't assume any level of confidence past much more than a decade or two. That too is the nature of good predictions, right? By definition, the further in the future we predict, the greater the margin for error.

Tangent - One possibly important area of difference between men and machines is the response when predictions are in error. I wonder how any machine now or in the near future would deal with fundamental errors such as discovered by Vera Rubin in galactic rotation, or the various Nobel Laureates seeking to measure how much expansion was slowing down. It would take a savvy programmer to "if then this" such deep prejudice. It may be a cause for pause and check in humans but may cause a computer to crash :)

Anyway, good conversation... made me think a lot.

 

[mfb]

I don't assume any level of confidence past much more than a decade or two.

Well, we won't have manned flights to Mars for a decade or two.

Also, one manned mission to one robot is not a fair comparison. For the price of a manned mission for a few months you can send 10+ robots, exploring 10 different locations potentially for years.

Tangent - One possibly important area of difference between men and machines is the response when predictions are in error. I wonder how any machine now or in the near future would deal with fundamental errors such as discovered by Vera Rubin in galactic rotation, or the various Nobel Laureates seeking to measure how much expansion was slowing down. It would take a savvy programmer to "if then this" such deep prejudice. It may be a cause for pause and check in humans but may cause a computer to crash :)

Such a fundamental discovery won't happen on a daily basis, and then light travel delay does not matter (even humans would ask for assistance from experts on Earth). If it is a mission-critical thing: losing a rover is better than losing an astronaut.

 

[1oldman2]

It appears as if the designing of habitats is big business, This seems to be representative of the current programs being worked on.
http://www.nasa.gov/feature/nextstep-partnerships-develop-ground-prototypes
http://www.nasa.gov/press-release/n...p-prototypes-concepts-for-deep-space-habitats

 

[enorbet]

Well, we won't have manned flights to Mars for a decade or two.

Already agreed upon and stated by most here, including myself, throughout this thread.

Also, one manned mission to one robot is not a fair comparison. For the price of a manned mission for a few months you can send 10+ robots, exploring 10 different locations potentially for years.Such a fundamental discovery won't happen on a daily basis, and then light travel delay does not matter (even humans would ask for assistance from experts on Earth). If it is a mission-critical thing: losing a rover is better than losing an astronaut.

If we agree that at least for a little while longer it is not possible to make anything close to a human capacity equivalent machine in the same volume and mass and that perhaps the greatest leap from walking on the Moon to walking on Mars, is money applied over that decade or two, and furthermore that it is an important goal for Mankind to become Space a faring species, all I'm asking is that a wee bit more money and thinking be spent to that end.

Please do recall that most experts in the field thought JFKs challenge in 1961 to put a man on the moon by the end of the decade as farfetched and fanciful given it was little more than 2 years after we finally managed to put "a basketball" in orbit. It is now quite impossible to imagine what the world would look like and what it would mean to live in it had that challenge, and those funds (which iirc at it's peak never exceeded ~4.5% of the annual Federal Budget, but is currently less than one half of 1%) not occurred.

FWIW of course humans on Mars would still need coms to Earthbound humans, but not anywhere near as often as machines, plus humans accompanied by machines would reduce that delay as well. That substantially improves efficiency and benefit per unit cost.

 

[mfb]

If we agree that at least for a little while longer it is not possible to make anything close to a human capacity equivalent machine in the same volume and mass and that perhaps the greatest leap from walking on the Moon to walking on Mars, is money applied over that decade or two, and furthermore that it is an important goal for Mankind to become Space a faring species, all I'm asking is that a wee bit more money and thinking be spent to that end.

We agree, and money does get spent already.

I'm not sure if space exploration would have looked completely different without Apollo. LEO space stations didn't need that project, and the mission to moon could have been done at some later point.

 

[enorbet]

We agree, and money does get spent already.

Note I didn't say no money was being spent, only that it is roughly 1/10th of Apollo era now.

I'm not sure if space exploration would have looked completely different without Apollo. LEO space stations didn't need that project, and the mission to moon could have been done at some later point.

Well I did say "the world and life in it" but even if we just focus on space exploration, please note that Russian exploration developed over somewhat different lines (big boosters) because they were a bit behind the US in miniaturization and computers back then. Considering Saturn V was developed specifically for Apollo, there is at least some doubt that US boosters would be as advanced as they are now, or hope soon to be. That must certainly qualify as a "Butterfly Effect" event, impossible to calculate the impact of never having built it nor fostering the level of inter disciplinary scientific and corporate cooperation required by the Apollo rush to the moon.

 

[GTOM]

Why do you expect a linear relationship between g on the surface and atmospheric pressure?

Without solar wind, the key quantity is the average kinetic energy of the molecules (in the upper atmosphere) compared to the energy necessary to escape from the planet. The escape velocity is about 5 km/s for Mars, for Earth it is 11.2 km/s.

Let's take Earth: T=2000 K, E=3/2 kT = 250 meV (the hot temperature is driven by solar radiation).
The necessary energy to escape for Helium is ##\frac{1}{2} m_{He} v^2_{esc} = 2.6 eV = 10.4 * 250 meV.
While it is rare, some helium atoms will get 10 times their average energy (and move upwards), and escape. Over geological timescales, most helium atoms escape.
Elementary nitrogen needs 3.5 times this energy, or ~35 times the average energy. That is really rare. Molecular nitrogen needs even more energy.

=> on Earth, helium escapes, but nitrogen does not (not including effects of solar wind).

Sorry, but still don't understand it fully. So escape speed is half on Mars (compared to Earth), kinetic energy is divided by four. But the rad dose from Sun is also about half (based on square of distance). That makes me think (of course i can be wrong), that chance to escape is twice that much, is that enough for such thin air?
Lighter elements also escape from Earth. Isnt it possible, that while lighter elements escaped from Mars, the heavier ones (nitrogen, molecules with oxygen) are rather frozen, captured by regolith?
How can we estimate the amount of ice on the caps?
About the speculation, what can be underground : https://www.nasaspaceflight.com/2015/09/nasa-confirms-salt-water-flows-mars/

 

[mfb]

The chance of thermal escape depends on the temperature, which depends on the solar radiation but not in a linear way. The temperature on Mars is more than half the temperature of Earth (absolute temperature of course). Yes, thermal escape is significantly easier on Mars. Which means helium escapes very quickly, but the heavier elements still stay around for a long time.

 

[GTOM]

The chance of thermal escape depends on the temperature, which depends on the solar radiation but not in a linear way. The temperature on Mars is more than half the temperature of Earth (absolute temperature of course). Yes, thermal escape is significantly easier on Mars. Which means helium escapes very quickly, but the heavier elements still stay around for a long time.

Thank you, but if you don't mind, i'd still like to ask.
Venus avarage temperature is 737 Kelvin, more than double of Earth, while gravity is smaller. Why doesn't it loose its atmosphere?

 

[mfb]

See the calculation I did in post 111. The temperature at the surface does not matter, the temperature is relevant at a place where atoms can escape without further collisions. The atmosphere of Earth is quite hot at that place, and still most elements cannot escape.

 

[GTOM]

See the calculation I did in post 111. The temperature at the surface does not matter, the temperature is relevant at a place where atoms can escape without further collisions. The atmosphere of Earth is quite hot at that place, and still most elements cannot escape.

Ok, thanks.

 

[GTOM]

https://www.nasa.gov/feature/jpl/mars-ice-deposit-holds-as-much-water-as-lake-superior

How could we extract that water from the regolith?

 

[DHF]

https://www.nasa.gov/feature/jpl/mars-ice-deposit-holds-as-much-water-as-lake-superior

How could we extract that water from the regolith?

Here is article on how they plan to mine water on the Moon. I expect similar methods would be used on Mars.

http://www.space.com/7350-nasa-hopes-water-moon.html

 

[mfb]

It should be easier on Mars as you directly have water ice. Maybe something like this: Dig or drill through the surface layer (1-10m) and put the material aside (can be used to cover habitats as radiation shielding). Continue excavating (now with >=50% water ice content), but this time put the material in a box, close the box once full. Heat it (concentrated sunlight, or worst case electricity).

(A) Let the water in the produced slush leave the chamber via a series of filters. Pressure can be provided by evaporation, some stirring looks useful but no pumps are needed. Dump the rest, clean the filters if necessary, repeat.

(B) Alternatively, use the vapor only: let it go to a box that is not heated, then just wait. Water/ice will accumulate there. Takes longer, even with a heat exchanger system, but the water will be very pure. Once the rate of water extracted gets too low, dump the rest, repeat.

 

[GTOM]

How much delta-V could be saved by aerobreaking when descend to Mars? 1-2km/s?

What could be the daily routine to sustain a small colony with local resources?
Cleanse solar panels? Filter the dust for peroxides, water, dry ice? Is it something like dewfall on Mars?
Fergitilize plants, check everything, whether maintenance needed?

 

[mfb]

How much delta-V could be saved by aerobreaking when descend to Mars? 1-2km/s?

Coming from Earth, you enter the atmosphere at about 6 km/s. A heat shield followed by a parachute can slow you down to less than 1 km/s, which leads to about 5km/s delta_v from the atmosphere.

Take care of food production, fix things that break (preferably remotely if outside), produce new things and install them.

The atmosphere has a little bit of water vapor, but extracting ice from the ground looks much more interesting.

 

[GTOM]

Isnt terribly new, but i found that one now.

https://phys.org/news/2017-03-nasa-magnetic-shield-mars-atmosphere.html

Does it sound something realistic in next hundred years for example?

 

[Al_]

Spending a long time in cramped quarters is not fun and provokes enduring psychological issues. A mission to Mars would land a menagerie of psychologically impaired people in a hostile. alien environmnet. That is a recipe for disaaster, IMO.

Exactly. I think that we should concentrate on building large, comfortable free-flying space stations (perhaps with spinning to create artificial gravity) and build and sustain them with robot mining, so they have freely available resources. Then we can head off to Mars in comfort and safety, using plenty of shielding, using the large amounts of fuel available, having lots of know-how about growing our own food, and with off-the-shelf mining robots and virtual reality controllers to operate them. We stop at Deimos to find easily available resources, and send robots down to prospect for a good landing site. Or just to prospect.

 

[mfb]

Magnetic fields are irrelevant on timescales interesting for humans. Sure, if you install such a magnetic field and wait for a few million years, Mars will have a slightly thicker atmosphere. But who wants to wait that long? And who wants to use 21st century technology for a multi-million-year project? People in 3000, assuming humans are still around, will laugh at our attempts, long before the artificial magnetic field would have any notable effect.

Similarly: If we find a way to give Mars an atmosphere, just do it and don't worry about the magnetic field. It doesn't make a difference if we add it in 2100 or in the year 210,000.

 

[nikkkom]

Exactly. I think that we should concentrate on building large, comfortable free-flying space stations (perhaps with spinning to create artificial gravity) and build and sustain them with robot mining, so they have freely available resources. Then we can head off to Mars in comfort and safety, using plenty of shielding

...and meet children of those who dared to endure "cramped quarters".

 

[GTOM]

Magnetic fields are irrelevant on timescales interesting for humans. Sure, if you install such a magnetic field and wait for a few million years, Mars will have a slightly thicker atmosphere. But who wants to wait that long? And who wants to use 21st century technology for a multi-million-year project? People in 3000, assuming humans are still around, will laugh at our attempts, long before the artificial magnetic field would have any notable effect.

Similarly: If we find a way to give Mars an atmosphere, just do it and don't worry about the magnetic field. It doesn't make a difference if we add it in 2100 or in the year 210,000.

What about the other issue, radiation protection? (As far as i know, high speed charged particles are a significant percent of radiation hazard) Simply pack another layer to houses easier, however, glass houses are better for plants, they also need rad protection.
Also if we build in a space station in orbit (to eventually convert it to a big mothership for travel) than thicker walls require more material, and launch from surface is expensive.

 

[mfb]

The proposed magnetic field is irrelevant for galactic cosmic rays, and probably doesn't much against strong solar flares. People on Mars will need radiation shielding anyway - either an atmosphere or some solid material.

Also if we build in a space station in orbit (to eventually convert it to a big mothership for travel) than thicker walls require more material, and launch from surface is expensive.

How is that related to the discussed magnetic field?

 

[GTOM]

The proposed magnetic field is irrelevant for galactic cosmic rays, and probably doesn't much against strong solar flares. People on Mars will need radiation shielding anyway - either an atmosphere or some solid material.How is that related to the discussed magnetic field?

So, a strong magnetic field doesn't seem to be an easier way for rad protection, than simply lift more mass (whether on a planet, or during the trip to Mars).

 

[_PJ_]

I really feel that any permanent residency on Mars is reallistically a LONG way off.
Sure we could (technology and determination, not budget/psychology)establish some form of habitat that could sustain life within 50 years - however, so few people would be there and a single 'disaster' could threaten everything.
For maybe 6 month, 2 maybe even 5 year extended trials - an equivalent kind of research station (As is found in Arctic, Antartic, now the ISS) seems to be a tried and tested foray into remote and dangerous locations.

The real benefits, I feel, will come from enhanced automation capabilities of robots and AI in establishing and generally maintaining such a station until such occasions as human lives are absolutely required.

LONG term I see a larger scale terraforming (habitat, unlikely to be the entire world) endeavour to ensure a more sustainable, ' comfortable' and safer environs for people

 

[nikkkom]

I really feel that any permanent residency on Mars is reallistically a LONG way off.
Sure we could (technology and determination, not budget/psychology)establish some form of habitat that could sustain life within 50 years - however, so few people would be there and a single 'disaster' could threaten everything.
For maybe 6 month, 2 maybe even 5 year extended trials - an equivalent kind of research station (As is found in Arctic, Antartic, now the ISS) seems to be a tried and tested foray into remote and dangerous locations.

Antarctic is not developed/colonized due to treaties prohibiting that.
ISS is a tried and tested foray how to NOT go about expanding into space.

I suggest we try something new, which is also a rather old method: after we have initial tech working reasonably well, send people to Mars who volunteer to go there intending to stay. Colonies on Earth were not generally planned as 5-year stints. _That_ method often worked remarkably better than ISS or our Moon program.
And if you don't like cramped spaces, please reread carefully: "volunteer". Nobody will force _you_ to go.

 

[rootone]

intending to stay.

That's the problem really.