KSK

Agreed. However I am encouraged by the quantities of minerals that seem to be there and that some of them are reported as being present in forms that I think are bioavailable. Hence Martian soil may not need a lot of processing and so be economically useful for agriculture. Whether Mars has industrially economic sources of those elements is a whole other question though, yes. Good point about selenium. I really don't know much about this other than what I've read, which is why I can be a bit pedantic about sources, and fessing up to the fact that I'm normally relying on a single source. From a quick search though it seems that selenium is found as a trace element at Gale crater. Then again, so is lead. I don't know how that would affect a growing plant or, more importantly whether it would be sequestered in that plant and so get into the colony food chain. Speaking as a chemist, 50 essential elements seems like quite a lot given that there are only 92 naturally ocurring elements and that quite a few of those are toxic, radioactive or chemically unreactive. But - like I said, I don't know much about this - if you could find a reference for that longer list of plant nutrients, I'd be interested in reading it. From a bit of searching it seems that selenium can be beneficial to plants but there's a debate as to whether its essential. It does seem clear that there's quite a fine line between a beneficial Se concentration and.a toxic one for plants. Speculatively, I'm wondering if some of the other 50 elements on your list are also 'beneficial but may not be essential'.

Okay, I’m pulling these figures and other information from Wikipedia. I’m assuming that planetary geology and plant nutrition aren’t particularly emotive subjects, so this information is unlikely to be maliciously wrong or subject to edit wars. With that said, if anyone cares to provide alternative sources, then please do. Plants require nine macronutrients (carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, sulphur, calcium and magnesium) and at least another eight micronutrients (iron, boron, chlorine, manganese, zinc, copper, molybdenum and nickel). Plants are over 95% carbon, hydrogen, nitrogen and oxygen by mass. Micronutrients are present at around 0.02% or lower. So 45kg of rice would contain roughly 9g of the most prevalent micronutrients, assuming that my mental arithmetic isn’t letting me down. Some micronutrients are present at 1000x lower levels (0.1ppm vs 200ppm), so around 0.009g in 45kg of rice. There is water on Mars. That takes care of our hydrogen requirements. Mars’ atmosphere contains carbon dioxide, so carbon and oxygen are available too. Martian soil contains, amongst other elements: magnesium, phosphorus, sulphur, chlorine, potassium, calcium, manganese, iron, nickel and zinc. All are available in reasonable quantities, that is the relevant minerals are present at around 1-10% by weight. Soil in this context refers to unconsolidated particles below 10cm in size, including material that is fine enough to be transported by wind. In other words, stuff you can go and dig up relatively easily. Inasmuch as anything is ‘easy’ on Mars of course. Where does that leave us? The most obvious nutrient we still need to supply is nitrogen. Then we need to find some boron, copper and molybdenum to complete our set of micronutrients. We may need some other elements too but presumably only at micronutrient levels or lower. Curiosity has found veins of boron containing minerals on Mars. Molybdenum and copper have been found in Martian meteorites. Mars’s atmosphere contains about 1.5% nitrogen. That’s not going to be easy to exploit but it is there. Perhaps more usefully, Curiosity has found evidence for biologically useful nitrogen) that is, nitrates) on Mars. TL: DR. Most of the nutrients needed to support plants are available in Martian soil or air. Molybdenum and copper may be harder to find but both are apparently present. Both are also extremely useful industrial metals, so one might expect some effort being made to find workable sources of them for a Mars colony. Nitrogen may be a bottleneck depending on the quantities of nitrates that can be found, although it is also present in the Martian atmosphere. Edit. I completely agree that food production is only one aspect of getting a Mars colony going. Having a working industrial base capable of supporting all other activities (including food production) will be the cornerstone of a self-sufficient Martian colony, assuming such a thing is possible. However, I personally find Martian agriculture to be an interesting concept and one that I’ve done a little reading around as research for my KSP fiction (in which my Kerbals have an extremely pressing need to be able to grow plants on Duna).

Interesting chat! My headcanon has a kerbal’s surname as a sort of group identifier but there are only two groups and they’re not at all socially rigid, or hierarchical, so they’re not what I’d really think of as castes. @roboslacker knows all this already but very briefly, there are two intelligent species on my headcanon Kerbin - the Kerbals and the Kerm. The Kerm are trees and they have a very long history and indeed prehistory with the Kerbals. Due to certain historical events, a breakaway Kerbal sect formed and declared themselves to be independent of the Kerm. In the language of the time they were Kerm-an - which, of course, has since been shortened to Kerman. For a variety of peaceful reasons that independence movement failed and Kerbal society evolved into two interdependent groups; the Kerman and the Kermol. Very loosely, the Kermol are farmer-priests - they tend to the Kerm and in return the Kerm provide enormous benefits for Kerbal agriculture. The Kerman are more technologically minded and their society (again very loosely) is a European style social democracy. They have a market economy, capitalism is a thing but for various societal reasons it’s quite strongly moderated - the extremes of wealth and poverty that you see here on Earth, aren’t really a thing on Kerbin. In-game of course, you never get to see the Kermol, so the only Kerbals you encounter are Kerman. Sorry about the wall of text - I promise you that was the short version!

You’re absolutely correct I did miss that - because it’s not shown in the article summary and I don’t have access to the full article. Your article summary states that vegetarian mothers have lower levels of DHA in their milk. True. The article summary also specifically states that essential fatty acids are a nutrient to which particular attention has to be paid to ensure sufficient supply. Lower DHA levels in milk is only a problem if that can’t be compensated for - which is not at all apparent from the article summary. Looking into this in a little more detail it turns out that there are algal sources of DHA. Interestingly it appears that these sources were discovered by a NASA research program into life support systems using plants, for long duration spaceflight. Since there is a plant based source of DHA available, then the ‘problem’ of adequate DHA for the children of vegetarian mothers is simply a non issue. Breastfeeding mothers can ensure that their diet contains sufficient algal oil. If breastfeeding is not an option for whatever reason, then the same oil can be added to formula milk. Anyhow. I’m done here. I’m trying to present my arguments politely and logically and not having that same courtesy extended back to me is getting tiring. Before I say something that gets this thread locked, I think it’s best if I bow out here. Thank you for the discussion.

And on a more light-hearted note, someone had to do it... Plane by plane, pilots baffled, trumped, tethered, beaten. Look at that Converter then Uh oh, what d’ya know, tree critters, frozen poop. But it'll do, save yourself, serve yourself. Darkness serves its own needs, listen to your friend bleed; Tell me that the Empress and the Servant’s in the right, right? You vitriolic, patriotic, slam fight, bright light. Feeling pretty psyched... It's the end of the world as we know it It's the end of the world as we know it It's the end of the world as we know it and I feel fine.

On the contrary. I took care to point out that eating meat makes it easier to obtain a balanced diet and that a vegetarian diet requires certain supplements. As for a vegetarian diet being healthy, well in the most literal sense of ‘can you eat only plant matter and survive’, then no it’s not because it’s missing some essential nutrients. However, beyond that very literal sense ‘health’ is a difficult thing to define. Take the traditional Inuit diet for example. It’s very high in meat and fat but, because a lot of that meat is consumed raw, can provide the required nutrients. However, at least according to that article, it’s also associated with higher than average mortality due to stroke. Does that make it a healthy diet? I don’t know the answer to that question. However, with some dietary care (which I think we can assume in the context of a Martian colony) and addition of a small number of supplements, it is possible to make a plant based diet healthy in your literal sense of ‘providing all required nutrients.’ My point is that this plant+supplement diet would be far easier (edit - and more efficient) to maintain on Mars than having to deal with the additional complications of off-world meat production.

I fail to see what on Earth (or Mars for that matter) your chicken pig cells have to do with synthesising food from hydrocarbons. Caviar made from oil I was not aware of and I’d be happy to read any article on the subject you care to link to. Margarine I’m well aware of. It’s made by hydrogenating unsaturated plant oils, thereby reducing their saturation (that is number of carbon-carbon double bonds they contain), thereby raising their melting point sufficiently that they become solid at room temperature. However, plant oils in this context are not hydrocarbons. Typically they will be esters of glycerol and long chain fatty acids (mainly di and tri esters) although they may also contain free fatty acids.

I disagreed with your statement that: “If women are to have children on Mars, then meat will be needed during pregnancy and breastfeeding or children will start dying.Vegetarianism is not a good idea, and it is certainly not proven idea, so it can not be said that it is healthy.“ As I said, meat is not needed for a balanced diet although it makes it easier to obtain. In the interests of an honest discussion, I pointed out the obvious exception that would prevent an entirely plant based diet from being viable. However B12 can be and is produced by bacterial fermentation, hence no meat is required for adequate B12 consumption. From the article you linked: “The American Dietetic Association's position is that appropriately planned vegan, lacto-vegetarian and lacto-ovo-vegetarian diets ensure a normal course of pregnancy and lactation. However, in practice the balancing of such a diet can pose certain difficulties, especially for individuals without the necessary experience or knowledge about nutrition. Nutrients to which particular attention needs to be paid to ensure their sufficient supply include: protein (essential amino acids), Omega-3 essential fatty acids, iron and calcium as well as vitamins D and B(12). The proper adherence to recommendations can be attained with a varied diet containing suitable plant products compensating for the nutritional value of the eliminated animal products. Supplementation with vitamin D and vitamin B(12) is also necessary. Research shows that infants born to vegetarian mothers are born at term and have normal birth weight. There is an increased risk of hypospadias in boys. The main difference in the composition of vegetarian mothers' milk compared to non-vegetarians' is lower content of docosahexaenoic acid and higher content of Linoleic and α-Linolenic acid.“ I think that summary actually supports my position rather well. Again, I disagree, for the reasons stated above. B12 can’t be replaced by plant ingredients but a perfectly viable alternative exists for people that choose not to eat meat or may find it impractical to eat meat. If a viable alternative exists then giving up meat is far from a stupid idea.

I’m sorry but I’m really going to need some sources for that. If I’m being pedantic and assuming that you’re talking about literal hydrocarbons (as in compounds that only contain hydrogen and carbon) then I can’t think of a single food, artificial or otherwise, that can be made solely from those. If I’m being less of a pedant, then lipids are mostly hydrocarbon but you’re not going to get very far feeding your colonists nothing but lipids. Carbohydrates and proteins certainly aren’t hydrocarbons. Synthesising some amino acids from simple precursors is certainly possible (see the classic Miller experiment for example) but I suspect synthesising all the necessary amino acids isn’t so straightforward. Carbohydrate chemistry is generally a pain. Sure you can. If you’re using hydroponics you do exactly what you’ve proposed - sterilise your vessels, replace your liquid medium and restart. And just like you wouldn’t trust your food production to a single vat, you wouldn’t trust it to a single hydroponic bed either. Likewise if you’re using soil, then you’re more likely to be looking at using separate containers (essentially large plant pots) of soil. If you get an infestation, empty and sterilise the pot, steam clean the soil and replant. I’m not proposing to have actual fields on Mars - that would be stupid for all the reasons you mention. Multiple greenhouses (for redundancy and damage limitation if you do happen to get an insect problem), growing plants in pots or multiple raised beds (for more redundancy). I think we both agree that there’s no room for actual livestock in an extraterrestrial colony. Sorry for any confusion there - I think we may have been talking past each other.

Disagree. A balanced diet is important and animal products make it easier to obtain certain nutrients but in most cases it’s also possible to get them from plant sources. Source. A notable and important exception is vitamin B12 which would either need to be produced on-site by bacterial fermentation (as it is on Earth), or shipped out to Mars in the form of vitamin pills. I think the latter is more likely and either would be a lot more practical than raising livestock on Mars. Enough people do to make it a viable business sector which creates a decent selection of products to choose from. Personally I wouldn’t like to dismiss all those people as abnormal but your mileage may vary. Given the real and actual risks of that high radiation environment, I’d be okay taking my chances with a suspicion of carcinogenicity in soy. I’d regard that as an acceptable risk from the benefits of eating a complete protein source (as in, contains all essential amino acids). Admittedly I’d also want to consume other plant proteins for balance and variety. To be honest, I’m surprised by that given the various Mars studies that have been published over the years. But regardless of that, I already agreed that your questions were good ones. And my own ‘best way forward’ answer might turn out to be utterly unrealistic once somebody does run the numbers, or has already been shown to be unrealistic. But I do find the automatic assumption that a Mars colony would need meat to be a curious one, and not one that I’ve seen good arguments for.

Starting to think I’m being trolled here. I’m also curious as to how much experience you have with synthetic chemistry, if you’re seriously proposing to use it to feed a colony. Because clearly treating ailing plants with chemicals isn’t a thing. Likewise sterilising growth medium. Also, depending on exactly what is afflicting your plants, there’s a decent chance of still getting a useful crop before cleaning up your field/hydroponic bed and starting again. Not so much for an infected vat. Hang on a minute. Pretty sure I already said something relevant here...Ah yes - here we go: “A ‘meat for meat’s sake’ system where you’re producing one nutrient source purely to feed it to a second nutrient source is, in my view, too wasteful of space and resources to be a good option.” Please do tell me how raising pigs or cows fits into that viewpoint.

Good questions. I don’t have any special insights to offer other than anything I - or you - could find online. I’m wondering whether you could make things slightly easier by not having your ‘farmland’ be a shirtsleeves environment (easier to build something that only needs to withstand enough of an atmosphere to sustain plantlife), or whether that would be more trouble than it’s worth. But yes, I agree with you. Having enough living space and being able to produce air, food and water are pretty basic first steps to a self-sustaining colony - and they’re all pretty formidable problems in their own right. Growing crops wouldn’t be without its problems (growing space being a very significant one) but I still think they beat, or are at least competitive with the alternatives that have been proposed here. A ‘meat for meat’s sake’ system where you’re producing one nutrient source purely to feed it to a second nutrient source is, in my view, too wasteful of space and resources to be a good option. Especially as I doubt it’s even going to produce anything that much resembles actual animal meat. I could maybe see the psychological benefit (if not the nutritional benefit) to creating actual grillable meat on-site, but if all you’re producing is bizarro protein paste, then I just don’t see the point in not going with vegetable proteins in the first place. Unicellular foodstuffs, whether they be Quorn-alikes or genetically engineered chicken/pig/algae/t-rex hybrids, still take space to produce, will probably need to be cultured under fairly stringent conditions to avoid contamination with other microorganisms, and will probably also require considerable processing to turn the raw cell-stuff into food. Go look up the Wikipedia article on Quorn for an example of the sort of things that would be involved. Purely synthetic food produced through bulk chemical synthesis seems...complicated and inefficient with waste products that are unlikely to be much use for anything. For my money, you want a chain of foodstuffs, where each is edible in its own right and in which the waste material from growing and processing one foodstuff can be used to grow another. As an off-the-cuff example: Hydroponically grown soy beans are processed into soymeal. The waste husks are ground up and used as a substrate for growing mushrooms. Whatever’s left after that is mixed with the waste foliage from bean production and composted down to be mixed with regolith and biowaste from the colonists. Conveniently, the perchlorates in that regolith are a pretty good source of chlorine for sterilising the biowaste. Net products - decent soil for growing more food and two foodstuffs, both of which are relatively low maintenance to grow (compared to vat grown food), and one of which can be cooked and eaten directly. I have no idea how practical that particular example would be but a system working on similar principles would be the way forward in my opinion.

Or you could just grow soybeans. They can be grown hydroponically, they're a complete source of protein and plants are a heck of a lot easier to grow and maintain than your cultured cell goop. We also have rather a lot of experience in turning soymeal into more palatable foodstuffs and of cooking with those foodstuffs. Despite its genetic background, I would be astonished if your chimaera ends up tasting much like either meat, at which point you've basically lost its sole advantage over soy. Growing soy also gives you the incidental psychological benefits of having greenery around and of having actual living things to take care of. Plus the plants contribute to your CO2 scrubbing systems. As for colonising Mars as a backup option in case of asteroid strike - I'm with whoever said 'why not both'. For the foreseeable future, I don't see a Mars outpost being anywhere near self sufficient, ergo if Earth loses the capacity to send supplies to Mars then the 'colonists' are doomed anyway. Having Mars as a second cradle for humanity is such a long game plan that you probably also want to have a way of deflecting that '0.01% probability in the next couple of centuries' impactor. As a personal aside, I find the notion of a year or two being sufficient to plan, build and launch an asteroid redirection mission to be hopelessly optimistic. Humanity as a whole is simply too divided, selfish, resistant to change and distrustful of those giving unpalatable advice, to have a hope in heck of doing anything about an asteroid strike. Besides, even assuming that my cynicism is unwarranted, all of our proposed methods for asteroid deflection work better if we have as much time as possible to implement them.

On the other hand, the plausibility of his death made his survival all the more of an emotional rollercoaster. Plot-wise, we'd already seen that the Empress and Roland are far more than they seem and that she's been watching over Val for most, if not all, of her life. So I didn't find it too much of a deus ex machina to have her step in now. As for saving Berdous too... I think we're going to find that he's been promoted to the ranks of Main Characters. And I suspect the reason why can be expressed in a single word. IVAN.

Imma gonna kill him. Gonna reach down his throat, pull out the first purple wobbly thing that I find and club him round the head with it. You do not do this to me, Writer Man! The kerbal was dead, impaled like a creva on a spit. I felt him go, heard him leave, saw his light gutter and die... But to everything there is a season - and a time for every purpose under the heavens. It was not the kerbal’s time... You do not do this to me, Writer Man!

No. If all Kerbals have the same surname then it becomes meaningless as an identifier. So either they have a life cycle where genetic similarity to other Kerbals is a non-issue, or they have some other way of establishing family ties and connections by which they can guard against inbreeding. Unless you had some other concern in mind of course.

Feeling kind of sucker punched right now. I guess that’s a good thing (it certainly speaks volumes about the writing) but damn it doesn’t feel like it.

The speech bubbles look fine to me. Love Bob’s expression on that last panel compared to that leaping out of the lander grin on the second panel. Nice start!

I agree with @steuben on both counts. This is a relatively quiet section of the forums these days, so I'd leave your poll a little longer. But most of all - write the story you want to write because that way you're more likely to keep writing it. Edit: If you really want my opinion, colonising Duna looks the most interesting.

Thanks! Don’t think the little rascals managed to abscond with anything. *pats pockets*

Best birthday present ever from my dear wife - a Keeper experience at the local zoo! Basically an hour going behind the scenes, getting to go into a couple of the enclosures and handling some of the animals. In my case an armadillo, a quite adorable wee owl, a couple of snakes (corn and royal python) and a tenrec. Which is basically a Madagascan hedgehog, about hand sized and cute as. This one decided that the palm of my hand was an adequately warm and comforting place to fall asleep. Also got face to face with some very curious meerkats. Most probably curious in a 'd'ya reckon he's gonna feed us, Bob?' sort of way. That was just in passing though and separated by wire mesh. Apparently they're a bit bitey, so that was probably for the best. Edit, I was not aware of this, but baby armadillos are soft-shelled and about golf ball sized. So I learned a thing today.

Hand-fed an armadillo and had a tenrec fall asleep on my hand.

Well I was willing to be persuaded but okay. Thanks for the conversation - and I mean that seriously.

All good links and I thank you. And yes I'm aware that there are links between mathematics and art - I gave one example myself. What I was objecting to was the statement that without mathematics and science there would be no art. I believe that is an exaggeration and I'm not seeing anything in those example articles to persuade me otherwise. All the more so if you generalise 'art' to 'the arts' and include things like poetry and literature as well as the visual arts. But as a concrete example, show me the mathematics in that Basquiat painting that @tater linked?

Well, in the absence of links or more convincing reasons other than a vague appeal to authority, I'm going to have to disagree with that statement. It rather smacks of Rutherford's 'physics and stamp collecting' quote, with its strong overtone of 'my stuff is more important because without my stuff your stuff wouldn't be a thing.' I can think of overlaps between art and maths and/or science (symmetry being a notable example), I can think of arts that have been enabled or improved by science but I disagree with the absolutist view of 'no art without maths or science'. But perhaps this isn't a discussion for this thread.