Wikipedia:Reference desk/Archives/Science/2009 September 27

= September 27 =

Question about the article "Psychological immune system"
According to this article, each persons view of the world, or reality, actually consists of a set of lies and biases, and that in order to keep our ego healthy, we continue to view reality through biased eyes whenever we are confronted with adverse situations, that could potentially cause our ego harm. Is my interpretation correct?

What really caught me by surprise is that, according to the article, each one of us has a biased view of reality, and that our brains subconsciously deceive us in negative situations by transforming reality into a psychologically more comfortable state. —Preceding unsigned comment added by 201.21.180.57 (talk • contribs) at 23:44, 26 September, 2009
 * Have you ever heard of denial, or perhaps repression? This is all this is. However, this theory is accepted only in some views of psychology, most notably the Freudian and neo-Freudian views. You may be interested in defence mechanisms, which gives more information on what you discuss.  Intelligent  sium  00:19, 27 September 2009 (UTC)


 * Our individual world view is sometimes called our "reality construct". More bluntly, in his book, The Way of the Weasel, Scott Adams concluded that we are not only weasels with each other, but with ourselves as well. →Baseball Bugs What's up, Doc? carrots 00:30, 27 September 2009 (UTC)

This same question was asked at the Humanities desk. →Baseball Bugs What's up, Doc? carrots 00:31, 27 September 2009 (UTC)

Diagrams of ancient earth
I was wondering if there was any one site that had alot of pictures of the earth like: http://en.wikipedia.org/wiki/File:Laurasia-Gondwana.svg At maybe 100 MA intervals (or at important times such as formation of supercontinents). Thanks~ 66.133.196.152 (talk) 01:33, 27 September 2009 (UTC)


 * You might find the Continents template helpful. I found plenty of maps for each of the major historical supercontinents, although it appears we don't have a single (easy-to-find) article that has a chronological line-up of maps.  However, many of our articles reference the same sources, including paleomaps at Northern Arizona University; this PaleoMap project, and its accompanying animations; and lots of others.  It seems that our Plate tectonics article is the center-point; we also have continent, with a great history section; but again, I can't seem to find a nice historical chronology with maps (even though we have maps on each separate article for each historical era - you can follow those links to each main article for maps and overview). Nimur (talk) 06:48, 27 September 2009 (UTC)

Thanks! Those sites are what I had in mind. 66.133.196.152 (talk) 12:53, 27 September 2009 (UTC)

Volume of mercury
Yes, this is a homework question. I've worked through the problem, got an answer, looked up the answer in the back of the book, and one of us is wrong.

The question is (I'm paraphrasing but getting all the figures straight): You have a beaker that has a capacity of 1000 cm3. There are currently 990 cm3 of mercury in the beaker. The temp is 20*C. At what temp (ignoring vaporization) does the beaker become filled to capacity.

The formula that I'm using is: deltaV = Vo * B * (deltaT)

With my values plugged in I have: 10 = 990 * 1.8x10^-4 * (Th - 20)

This gives me a high temp of 76.12*C where the beaker will be full. The book gives an answer 79*C. Who's wrong? Thanks, Dismas |(talk) 01:48, 27 September 2009 (UTC)


 * I get a different answer because the value I have for expansion of mercury is 182e-6C-1 (a little more exact). So, I get  TF=75.5C. To get 79C, you have to use an expansion of 171e-1C-1. --  k a i n a w &trade; 03:41, 27 September 2009 (UTC)


 * Did you consider the fact that the beaker also expands? Dauto (talk) 03:48, 27 September 2009 (UTC)


 * No, I hadn't. Hrm...  Dismas |(talk) 03:57, 27 September 2009 (UTC)


 * The beaker will not expand THAT MUCH in the course of 3C, the difference in temp between his answer and the books answer. It cannot be that.  The coefficient of expansion of glass is miniscule compared to that of mercury, much below the significant figure range; I wouldn't even consider it a factor here.  -- Jayron  32  04:02, 27 September 2009 (UTC)


 * jayron, think again... Dauto (talk) 04:28, 27 September 2009 (UTC)
 * Pyrex is used specifically because its thermal properties are negligible - preventing cracking, chipping, etc., even when rapidly changing its temperature. This supplier quotes 32.5x10-7/°C; this supplier confirms that value.  Expansion of the glass beaker is negligible.  Nimur (talk) 06:24, 27 September 2009 (UTC)
 * If the question had intended us to consider the expansion of the beaker, it would surely have specified what the beaker was made of because without knowing that, we cannot answer the question. We should definitely ignore that factor. SteveBaker (talk) 14:51, 27 September 2009 (UTC)


 * I tried integrating using the relation dv = B*v*dt, but that didn't give much difference. It, in fact, reduced to 75.58°C. I don't think you need to consider the expansion of anything other than mercury here. AFAIK, I think 75.58 must be the right answer, unless, as suggested above, you choose a different value for B.  Rkr 1991  (Wanna chat?) 06:14, 27 September 2009 (UTC)


 * This site from University of Denver quotes a quadratic rule for the thermal expansion of mercury:
 * "V(t) = V(1 + 1.82 x 10-4t + 7.8 x 10-9t2), where t is in °C, and V is the volume at 0°C."
 * It looks like the linear approximation may not be sufficiently accurate; this would seem to explain the discrepancy. Thermal expansion isn't really linear anyway - it's surprising that a linear approximation is ever good enough to work.  Compounding the issue is that we're considering a reasonably large temperate range - fifty or sixty degrees celsius - so a more sophisticated model is probably needed. Nimur (talk) 06:33, 27 September 2009 (UTC)


 * I really don't think those are needed for this text book problem. This appears to be a school-level problem, which certainly wouldn't utilize all these sophistications, unless explicitly taught in class, which I don't think is the case. So I would say our only option is to conclude that the textbook has made a mistake, unless someone can come up with something radically new...  Rkr 1991  (Wanna chat?) 09:08, 27 September 2009 (UTC)


 * That amount of nonlinearity doesn't make much of a difference. Using that quadratic equation for the volume, the solution is 75.46°C.  So it still just looks like the book is wrong.  Red Act (talk) 09:44, 27 September 2009 (UTC)


 * The beaker has a capacity for mercury that is greater than its nominal capacity1000cm3 and the reason is that the mercury forms a convex meniscus before it spills over.Cuddlyable3 (talk) 12:43, 27 September 2009 (UTC)


 * What exactly do you mean by "Nominal Capacity" ? Since the capacity of the beaker in question is said to be 1000cm3, we must assume it is so for mercury.  Rkr 1991  (Wanna chat?) 12:54, 27 September 2009 (UTC)


 * My book would not be taking into account a meniscus. We're just learning a bit about thermal expansion.  The formula that I provided is the one that we're to use.  I'm just going to chalk it up to publisher's error.  Thank you all for trying to help!  Dismas |(talk) 13:01, 27 September 2009 (UTC)
 * Again, if the question had intended us to take into account the meniscus, it would have had to say what the dimensions of the beaker is - a tall-thin beaker would hold less mercury than a short-wide beaker. (Strictly: It would also be necessary to tell us what the beaker was made of since the extent of the meniscus depends on that.)  So if we are intended to take the meniscus into account, the question would be unanswerable. SteveBaker (talk) 14:51, 27 September 2009 (UTC)


 * Please write to the principle author via the publisher. Probably his grad student made an error while slaving through the textbook questions. Sometimes such errors have appeared in several editions of a book. I have gotten back nice letters from such authors when I pointed out errors. Some schools have errata sheets they pass out which have corrections for booboos in textbooks. You might save other students the puzzlement you have experienced, but there is also benefit in learning to check your work and look for other solution methods to get the book answer, or back solving to see the possible origin of the erroneous answer. Does the erroneous coefficient 171e-1C-1 per Kainaw, correspond to some other element or common compound which would appear in the next line in the CRC Handbook of Chemistry and Physics, that the hypothetical underpaid overworked grad assistant might have looked at  when preparing the answer guide? Edison (talk) 14:13, 27 September 2009 (UTC)
 * This question should be saved for posterity as an example of the right way to ask a homework question here. --Sean 15:38, 28 September 2009 (UTC)

what disease is this
hi.... wat kind of disease is this fits?


 * Your question is hard to understand. Are you talking about epilepsy, maybe?  --Anonymous, 05:22 UTC, September 27, 2009.


 * A "fit" is a slang term for "a seizure or convulsion, especially one caused by epilepsy". So "fits" doesn't always refer to epilepsy, and is really more of a word for a symptom, rather than a disease.  Red Act (talk) 07:41, 27 September 2009 (UTC)
 * It is precisely a word for a symptom, not a disease. Epilepsy is kind of a symptom too - there is often a specific underlying cause (brain damage of some kind, I guess). In fact, there is probably always a specific underlying cause, just sometimes we don't know what it is. --Tango (talk) 09:37, 27 September 2009 (UTC)
 * Another possibility -- apparently Fifth disease is sometimes misnamed as "Fits disease". Looie496 (talk) 16:07, 28 September 2009 (UTC)

Body building

 * Question originally posted on the Humanities reference desk by user:Kanthasamy; moved here by me. --Anonymous, 05:30 UTC, September 27, 2009.

why the arms get unshaped
 * What do you mean? →Baseball Bugs What's up, Doc? carrots 05:52, 27 September 2009 (UTC)


 * See Bodybuilding  Rkr 1991  (Wanna chat?) 06:15, 27 September 2009 (UTC)

Tox-sick
Which is the best way to remove the toxins from our body i.e. liver,lungs,heart etc


 * What kind of toxins? Letting the body's own methods get on with it is usually best (there is certainly no point spending lots of money on "detox" products). For some toxins there are antidotes. If the toxin has been ingested and is still in the stomach it can help to either induce vomiting or consume something like charcoal to absorb the toxin so it can pass straight through you (don't try either of those without consulting a doctor, though). --Tango (talk) 10:40, 27 September 2009 (UTC)
 * Depending on what they're trying to remove, our detoxification article says doctors may use techniques such as dialysis or chelation therapy.


 * If you're asking about detox diets, though, you should remember that "Body cleansing and detoxification have been referred to as an elaborate hoax used by con artists to cure non-existent illnesses. Most doctors contend that the 'toxins' in question do not even exist." AlmostReadytoFly (talk) 11:44, 27 September 2009 (UTC)


 * "The toxins" implies the OP is believing the quackery and not referring to a specific toxin for which there is an antidote. Chelation therapy is recommended by some sites, without mentioning the risks (and the 30+ people who have died from it ). --Mark PEA (talk) 11:59, 27 September 2009 (UTC)


 * The OP doesn't say whether the question concerns long-term accumulated toxins or short-term poisoning. For critical poisoning one should know in advance what poisons one may have to handle (can children reach your household chemicals?) and know the local telephone number for poison information or hospital emergency. Ordinary emergency call operators have no chemical training. Nor do I think the Ref. Desk. should prescribe what medical treatment is "best". Cuddlyable3 (talk) 12:33, 27 September 2009 (UTC)

I just got it. "Tox - sick" - sounds like "toxic", that's clever. Cuddlyable3 (talk) 12:35, 27 September 2009 (UTC)


 * We need to be really clear on one point: The manufacturers of many, MANY 'quack' medicines and diets and stoopid pads you stick on the soles of your feet(!!) are being deliberately vague about "removing toxins". It's a great advertising bullet - but it's quite utterly meaningless.  In fact, these things do nothing to remove poisonous substances from your body.  They have zero effect (if you're lucky) or even add mildly toxic substances (if you're not lucky) because they tend to be based on herbal ingredients that escape proper medical testing thanks to a ridiculous legal loophole.


 * So if that vague description of "toxins" is what you're talking about - then forget it - stop worrying - you don't need to do anything.


 * However, if you're talking about a very specific toxin - such as the slow accumulation of lead in children in areas where lead-based paint or lead-based plumbing is common - then this is an important medical matter, and one that we, as a library reference desk, are not allowed to address. If you think you are getting slowly poisoned by something specific - then you need to take this seriously and go see a doctor as soon as possible - and possibly make a call to the EPA (or your local equivalent) to get the toxin removed from your environment.


 * SteveBaker (talk) 14:45, 27 September 2009 (UTC)
 * The ultimate challenge question, which succinctly summarizes Steve's commentary, is to demand from the manufacturer to clearly state which toxin(s) they remove. If they cannot provide a list, it is probably because it is illegal for them to claim something which has not been tested and shown to be true (or, it may recategorize them as a medicine, and force an entire new level of testing rigor).  This is the reason why so many phony products hide in the generic "de-tox" verbage.  But if they don't say what toxins they are removing, they are probably removing nothing.  Nimur (talk) 15:39, 27 September 2009 (UTC)
 * Maybe "money in the wallets of the gullible and scientifically-illiterate" is a toxin? DMacks (talk) 18:37, 27 September 2009 (UTC)
 * Could be. AlmostReadytoFly (talk) 21:19, 27 September 2009 (UTC)

Internet lines
Were specific communication lines built for the purposes of the internet or does the internet just utilise existing communication lines? Clover345 (talk) 18:05, 27 September 2009 (UTC)
 * Both. And some originally-built-for-Internet are also used for other modes. DMacks (talk) 18:35, 27 September 2009 (UTC)
 * (edit conflict) Both. You might want to read History of the internet. In the very very early days, computers were connected over special-purpose lines - e.g. a special data cable ran from Palo Alto to Menlo Park, between the Stanford University campus and the Stanford Research Institute. The next phase was to use a telephone line, with a suitable modem on each end, and a routing computer at each end. These early routers were called Interface Message Processors, and they were built at four or five sites (UCLA, Utah, Stanford, and SRI in Menlo Park - if I recall properly). Over the next few years, telephone became the mainstay of the internet. As the 1970s passed on to the 1980s, the telecommunications industry started to go digital - actually switching over to a packet-switching network that made up the core internet backbone lines. This makes it difficult to distinguish whether a particular "wire" was used for "data traffic" or "voice telephone" or cable television traffic - in fact, it was a shared network connection as early as the late 1970s and early 1980s. This is a huge concept - a packet switched network is shared by data, voice, television, telephone, and computer traffic. So, you lay down a single network connection, and use it for all telecommunication. By the late 1990s, internet data became the dominant economic force driving the increased network connectivity - and many network theorists and economists attribute the dot com bubble to the over-investment in excess network capacity - "dark fiber". Today, we are still reeling from that surplus - hundreds of billions of dollars worldwide of cabling and routing equipment purchased in the 1990s - which sits unused unless we waste it away on freely available, bandwidth-heavy activities. For better or worse, it is stimulating many other economic side-effects - for example, free long-distance voice-calls to almost any number in North America are now standard with any mobile telephone plan - because the traffic can be routed for virtually no cost through the backbones that crisscross our continent. So many of these exist that competition has driven the rates down to near-zero (in North America). Nimur (talk) 18:40, 27 September 2009 (UTC)
 * Nimur I disagree that YouTube that you linked to is a waste. Cuddlyable3 (talk) 23:27, 27 September 2009 (UTC)
 * In any case, it wouldn't exist if network connectivity cost as much as it did in 1985. We've seen an exponential falloff - you don't have to pay $400 to download the reference I just linked.  But somebody had to pay for that network connection.  Whoever did, lost a lot of money.  Nimur (talk) 23:36, 27 September 2009 (UTC)
 * There is a confusion here about costs of hardware and service that hardly justifies a perception that YouTube is a waste. Nimur is correct that connection costs in 1985 would have made YouTube a non-starter. YouTube was founded in 2005 using a combination of the latest video/audio data compression techniques and the Internet connections that were already established as commercially viable. YouTube is an added-value service and no one has lost money because of its activity (notwithstanding some copyright complaints). The fact that the YouTube founders were able to sell their enterprise for $1.65 billion is their serendipitous payback for innovation. We may bemoan the unfairness of that sum not being shared with network providers but unless you can show that YouTube has a major negative impact on operation of other Internet services, I don't think you should disparage it as a waste. The bandwidth relation of YouTube's Flash Video to non-video Internet services e.g websites, e-mail, search motors, Wikipedia, is analagous to the relation between analog TV- and radio- broadcasting. Cuddlyable3 (talk) 23:02, 28 September 2009 (UTC)
 * Here's a relevant news article - "US may need as much as $350 bln to extend broadband". Again, this serves to demonstrate that the installation of network capacity is a real cost, borne by somebody.  However, the productivity, commercial marketability, and internet startup companies, which require the internet connectivity, rarely pay in to the system as much as they extract from it after it is built.  I think this is the opposite of the "tragedy of the commons" - it is the "benefit" of the commons.  Some "benevolent investor" (typically a Tier 1 network provider) pays a huge sum of money to develop a network - and everybody except them profits off of it.  Nimur (talk) 20:54, 29 September 2009 (UTC)

Strange unit of weight, "OR" = 0.322 grams, what is it?
Oh, ye wise friends -

I have in my possession an odd weight, made of brass - you know, the typical cylinder with a knob on top, used for weighing on balance scales way back then...

The odd thing is the stamping, and the mass of this weight.

It weighs (as closely as I can determine on my digital scale) 1610 grams, i.e. 56.8 ounces avoirdupois.

The marking on the weight is - and here I am completely baffled, even an extensive Google search doesn't help:

"OR 5000"

Thus, one OR would be 0.322 grams...

What is an "OR" unit - does it have something to do with weighing gold, since "or" is French for gold?

Any enlightenment would be gratefully received.

Greetings, --Janke | Talk 20:45, 27 September 2009 (UTC)
 * The troy ounce, according to our article, is 31.1035 grams, and is used for weights of precious metals (please don't tell me about weight vs mass; in this context the word "weight" means precisely mass, in the sense of "quantity of matter", and always has). Maybe your scale is a bit off, or maybe there's something sticking to your brass weight? --Trovatore (talk) 20:50, 27 September 2009 (UTC)


 * Nope - 50 x 31.1034768 grams (one troy oz) would make it 1555 grams, not 1610. My digital scale is more exact than that, a 1 kg weight reads exactly 1000 grams. From its appearance, I'd say this weight is from the 1800s, and I think, in addition to the "OR" (French for gold), it may have a background in banking (the person who gave it to me has...) --Janke | Talk 20:53, 27 September 2009 (UTC)

French word order is the same as English for number-and-unit combinations: "10 minutes", for example, is written identically in both languages. It also doesn't make sense that "OR 5000" would mean "gold 5000". Having said that, I have no idea what OR does mean. Remember that the language might not be French: if "or" is a word in English and French, it could easily be a word in several other languages. And of course it could also be an abbreviation.

There doesn't seem to be any unit of measure on Russ Rowlett's web site that's about 322 milligrams, nor one with the 1.61 kg mass of the whole object, nor one whose name starts with the letters "or". There was an old French unit of weight/mass called the once, but that was similar in size to our ounce, about 30.59 grams. --Anonymous, 04:08 UTC, September 28, 2009.


 * Using this website, I cannot find ANY standard unit of measurement with 322 mg = 1 ANYTHING. The only thing even in the right order of magnitude is a carat (mass), and that was still pretty far off (1 metric carat = 200 mg, 1 British carat = 259 mg, and 1 "Board of Trade" carat = ~205 mg.)  Nothing else in any standard weight system anywhere I can find comes even close to that unit.  It's likely not an actual measure of unit, rather, it may be a mark that means something entirely different.  -- Jayron  32  04:30, 28 September 2009 (UTC)


 * Maybe it's the weight of gold equal to the value of 5000 of some particular currency. A lot of currencies were on the gold standard, and 322 mg of gold seems like it's in the range of plausible values.  Randomly looking through some of the pages on some European denominations I didn't find any valued at that amount but for instance the French franc was pegged at 290.32 mg of gold.  A weight like that would make sense for a bank to have, since they would need to be able to measure out the correct amount of gold to exchange for currency. Rckrone (talk) 05:29, 28 September 2009 (UTC)


 * Looking closer, I found one more stamping on the weight; "TARE FRANCS" - does that help? Google gives one (yes, only one!) hit, in a Latin text... Sure looks like Rckrone is on the right track, but the unit (if there is a unit involved) doesn't fit anything we know... --Janke | Talk 06:28, 28 September 2009 (UTC)


 * Hey, I'm on to something: 0.29032 grams of pure gold diluted to 90% purity (with, for instance copper or silver) would be very close to 0.322 grams. A Google search turned up this: "The Swiss 20 Franc Gold coin was minted in Bern and consists of 90% gold. . . . the gold Swiss 20 Franc coins are the most famous and were issued in Switzerland from 1897 to 1935." Can we consider this an answer to the original question? Any definite info, anyone? --Janke | Talk 06:59, 28 September 2009 (UTC)


 * One more hit: "Swiss 20 Francs coin, which contains 90% (.900 fine) gold. These coins, in as-minted, uncirculated condition, weigh 6.45 grams and contain .1867 Troy ounces of actual gold weight" - 6.45 divided by 20 gives 0.3225 - I think that's it! Thanks, Rckrone - you got me onto the right track... Now, I only wish I had those 5000 Swiss francs instead of the weight that only represents them... ;-) --Janke | Talk 07:06, 28 September 2009 (UTC)


 * Wouldn't that weight only represent 1 SF? Googlemeister (talk) 19:22, 28 September 2009 (UTC)


 * Good find!
 * Googlemeister: I don't really see how sig figs play into this. Are you talking about the discrepancy between 5000*(0.29032 g)/.9 ~ 1613g and the measured weight of 1610g? Rckrone (talk) 00:28, 29 September 2009 (UTC)


 * Rck, I'm sure Goog's abbreviation "SF" meant "Swiss franc" (more commonly Sfr. in traditional abbreviation or CHF in modern currency codes). Goog, the idea is that the 1610 g weight equals the weight of 5000 Swiss francs in gold coins of the relevant period.  Makes sense to me too.  --Anonymous, 04:18 UTC, September 29, 2009.


 * Indeed! Some sweet talk resulted in my obtaining a few more weights - in addition to the "TARE FRANCS OR 5000" weight, I now have brass knobs representing 200, 300, 500, 1000 and 2000 Swiss Gold Francs of the period 1897 to 1935! The discrepancy in the exact weight, 1612.5 grams and my 1610 g weighing result is most probably due to the tolerance of my digital kitchen scale... Now, I only need to know about the two smallest weights that I also got (they appear to be a different series altogether). They're marked 1M and 2M and weigh a little over 5 and 10 grams, respectively. Any ideas? --Janke | Talk 13:57, 29 September 2009 (UTC)


 * Oh I see, the weight is not 0.322 grams, the weight is 5000x larger. Googlemeister (talk) 14:18, 29 September 2009 (UTC)


 * One guess is the weight of some .900 fine silver Franc coin. The silver-gold exchange rate was fixed at 15.5 in France and probably elsewhere (Silver as an investment mentions this), and 15.5*0.32258g = 5g exactly (in fact this explains where the weird rate 9/31 g of gold = 1 Franc came from).  This link  mentions such a coin in 19th century France.  I don't know about a Swiss version, or what "M" is. Rckrone (talk) 19:40, 30 September 2009 (UTC)
 * The Swiss franc article has some information. They mention some of the silver coins used lower purity silver than 90%, which might explain why the weights are over 5g. Rckrone (talk) 20:10, 30 September 2009 (UTC)
 * Although the French franc article says the weights of the coins weren't changed from 5g when they went from 90% silver to 83.5% silver, and they're supposed to have the same value as the Swiss franc coins, so that explanation doesn't really make sense. Rckrone (talk) 21:17, 30 September 2009 (UTC)

is mars shit still sterilized
yo is mars shit still sterilized, now that there is 99% pure water on mars obviously anything we send there would bring lots of microbes that have no problems living there. now, i personally dont care if there used to be microbes before we put any there on ours mars shit but i bet a lot of scientists would, so is mars shit still sterilized so that the scientists can be sure that the life they discover is not earth microbes but mars microbes. also, is it true you could just pitch a tent on mars, and, as long as you had oxygen to breathe, you could be there in a tshirt and not explode from the zero pressure or freeze or burn up. are there any plans to camp out on mars.


 * Yes, Mars landers and still sterilised, as far as I know. The atmospheric pressure on Mars is so low that it would be considered a pretty good quality vacuum in a lab on Earth - you certainly couldn't survive without a spacesuit. --Tango (talk) 22:19, 27 September 2009 (UTC)
 * I can't think of a better sterilization method than an Earth-to-Mars transit: several months exposed to cosmic radiation, solar wind, intense cold, intense heat, the vacuum of space, and a total absence of nutrients and water, followed by a harsh atmospheric entry. There are extremophiles, but few can sustain that many different types of extreme conditions.  Nimur (talk) 22:29, 27 September 2009 (UTC)
 * It might be different with shuttles -- what with pressurised cabins and all. John Riemann Soong (talk) 22:39, 27 September 2009 (UTC)
 * Have you looked at the Mars article? It gives the surface temperature range on Mars as minus 87 °C to minus 5 °C, and that is like Antarctica on Earth. The atmospheric pressure on Mars is less than 1 kPa compared to our 100 kPa. Camping in a tent is not survivable, not even with your own oxygen and tshirt. Cuddlyable3 (talk) 22:55, 27 September 2009 (UTC)
 * Armstrong Limit. You would move around without a suit at least as long as in 2001:A Space Odessey. Sagittarian Milky Way (talk) 23:53, 27 September 2009 (UTC)
 * Also, mars is mostly CO2 atmosphere. our microbes are more adapted to nitrogen-oxygen, so that would also help to kill them off.  Googlemeister (talk) 13:45, 28 September 2009 (UTC)
 * Earth microbes could and likely do survive interplanetary flights. Not everything which goes to Mars is autoclaved. Edison (talk) 19:16, 28 September 2009 (UTC)

A discovery of excrement on Mars would revolutionise our knowledge of extra-terrestrial life. Cuddlyable3 (talk) 23:07, 28 September 2009 (UTC)

Making acohlo from water
How you making ackohol from plane water? —Preceding unsigned comment added by 79.75.61.101 (talk • contribs)
 * It isn't possible to make alcohol from nothing but water. All forms of alcohol contain carbon, which water does not contain.  Red Act (talk) 23:08, 27 September 2009 (UTC)
 * Maybe he was asking about an in-flight beverage? Nimur (talk) 23:11, 27 September 2009 (UTC)
 * Converting "water" into "wine" is a popular magic trick. But the magic trick doesn't really turn pure water into wine.  It's just a magic trick.  Red Act (talk) 23:18, 27 September 2009 (UTC)
 * The New Testament John 2:7-9 reports that Jesus made wine from water but the method is not disclosed. Cuddlyable3 (talk) 23:19, 27 September 2009 (UTC)
 * Of course, that's just a mythological story about something that didn't really happen. Red Act (talk) 23:42, 27 September 2009 (UTC)
 * Dear Jesus, these unbelievers Rev 21:8 are people that I don't even know. Jesus could have used the water to irrigate grape vines.Cuddlyable3 (talk) 12:14, 28 September 2009 (UTC)
 * Ok can I use air and water to cet the carbon?
 * Not easily. For a start, there is very little carbon in air - carbon dioxide makes up a fraction of a percent of the atmosphere. Almost all alcohol does, in sense, come from a mixture of air and water, though - plants turn the CO2 in air and water into sugar using photosynthesis (which requires sunlight), which is fermented into alcohol by yeast, or other micro-organisms. There is more involved in that process than just air and water, though. --Tango (talk) 23:37, 27 September 2009 (UTC)
 * (ec) Yes, you could, although that would be a painful process. The major source of carbon in air is CO2, which is at 380 ppm or so - or 0.04%. The well-understood way to make alcohol from water and air is to grow some sugary plants and then ferment the sugars into alcohol. You need some extra ingredients, but they really act as catalysts and are not used up (except for the sunlight). --Stephan Schulz (talk) 23:40, 27 September 2009 (UTC)

You could react ethylene with aqueous sulfuric acid .... you could acquire ethylene from that gas fruits emit when they are ripening. John Riemann Soong (talk) 23:51, 27 September 2009 (UTC)
 * And where do you get the sulfuric acid? --Tango (talk) 23:56, 27 September 2009 (UTC)
 * Fisher Scientific. Nimur (talk) 00:07, 28 September 2009 (UTC)

Are there any industrial imitations of the Calvin Cycle? Couldn't we toss the right enzymes in a solution of suitable pH and feed carbon dioxide into it? Maybe extract ethanol or acetic acid as products? John Riemann Soong (talk) 00:38, 28 September 2009 (UTC)


 * Its just far less complicated to let fresh fruit juice sit around and ferment. Heck, if pruno exists, it proves you can pretty much make alcohol from anything edible... -- Jayron  32  01:09, 28 September 2009 (UTC)


 * Well we're talking a large scale processes here. Economy of scale, etc. Hasn't anyone looked into the applications of a large pool of RuBisCO (& allies)? Seeing that CO2 is a major industrial output, we may have an environmentally-friendly solution (solution harhar) here. John Riemann Soong (talk) 05:14, 28 September 2009 (UTC)


 * Fusing two hydrogen (protium, to be exact) nuclei results in a deuterium nucleus and a beta particle. Fusing two deuterium nuclei results in a tritium nucleus and a free neutron. Fusing a deuterium nucleus and a tritium nucleus results in a helium-4 nucleus and a free neutron. Fusing three helium 4 nuclei results in a carbon-12 nucleus. This, along with the water, will give you hydrogen, oxygen, and carbon. Forming that into ethanol is comparatively trivial. Did I make any mistakes? — DanielLC 02:21, 28 September 2009 (UTC)