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March 29

Marsupials

When the fetal marsupial is in the mother's pouch, attached to a nipple, does it excrete waste? How do they keep from messing the pouch? If we have an article that answers this question, I haven't been able to find it. -GTBacchus^(talk) 01:34, 29 March 2009 (UTC)[reply]

they lick the pouch and the joey clean and consume the waste products. It seems that this is useful to recycle water lost in producing milk.[1] [2]--Lenticel ^(talk) 02:54, 29 March 2009 (UTC)[reply]

Thank you! -GTBacchus^(talk) 01:50, 30 March 2009 (UTC)[reply]

And lest any readers are inclined towards sub-therianism based on the practice, I'll point out that mother dogs and cats and presumably other placental mammals do the same. --Sean 17:05, 1 April 2009 (UTC)[reply]

Indoor Vs Outdoor Air Quality

I guess this is a sort of two part question.

I live near a rather busy main road and a thought randomly occurred. Would the air quality be better inside the house or outside. The roads are sort of layed out in this fashion:

^^^^^^^^ [Houses]
{------} [Service road for acess to houses and the driveway to houses, not very much trafic]
........ [Median strip aka small strip of grass with a couple trees]
===== [Main Road going in one direction]
........ [Seperator/Strip of grass&trees]

The whole thing is mirrored on the other-side.

—Preceding unsigned comment added by 121.220.48.94 (talk) 01:41, 29 March 2009 (UTC)[reply]

Your question is not answerable. Nobody here knows such things as:

Do you have mold in your house?
Do you have a sewer system running under the street?
Are you downwind from a paper plant?
Are you allergic to the trees along the road?

Four questions just to get you started. If anyone wanted to take time, they could come up with another four thousand pertinent questions. If you are truly concerned about the air quality around your house, get an air quality tester (they are sold in both Lowes and Home Depot here). If you are truly concerned about your health with the air quality around you, this is absolutely not the place to ask this question. You must seek professional medical help for health questions, not random opinions from strangers on the Internet. -- kainaw ™ 02:36, 29 March 2009 (UTC)[reply]

It was just more of a general interest question really..nothing too serious :-) 121.220.48.94 (talk) 03:32, 29 March 2009 (UTC)[reply]

Just about anything that is in the air outside the home will eventually make it's way inside the home due to air infiltration. That article discusses the measurement of "air changes per hour (ACHs)", and mentions ACHs in the range from 0.25 through 1.5. So all other things being equal, the inside and outside air quality would on average be the same. A passing poorly maintained vehicle may give off noticeably offensive fumes, but those fumes would quickly dissipate. However a small portion of those fumes may infiltrate the home and will linger for a while.

But of course all things aren't equal. Larger particulates might not infiltrate the home as easily as other pollutants, and those that do may be be reduced by air filters in the air conditioning system. On the other hand, the home is full of indoor air pollution sources. Naturally occurring radon gas, construction materials, household cleansers, cooking fumes (even if they smell good), perfumes and deodorizers, and even bodily methane expulsions all reduce the air quality. Given a choice, I'd prefer the outside. I could be wrong though. Big cities routinely recommend staying indoors during smog alerts, and now that I think about it, I'm not sure why. -- Tcncv (talk) 04:34, 29 March 2009 (UTC)[reply]

air infiltration is absolutely necessary. Every now and again you get someone who insulated their home so thoroughly that they asphyxiate inside e.g. [3]. Opening your windows during rush hour or smog alerts / high ozone levels may not be advisable, but there are bound to be times of low traffic on the road. There's a lot more air volume outdoors than indoors. That makes air exchange more efficient outdoors and allows fewer pollutants to accumulate. 76.97.245.5 (talk) 07:09, 29 March 2009 (UTC)[reply]

Well, we're certainly not going to be able to give you a clear "Yes" or "No" answer here. This is definitely an "it depends..." kind of question.

Smog - in it's truest sense of "Smoke Combined With Fog" - may well be a different matter indoors and out. Fog can only remain in the air in specific conditions of temperature, humidity and pressure. It's unlikely those pertain inside your house - so one of two things has to happen:

The fog condenses on some kind of surface - leaving a film of smoke particles wherever it condensed.
The water droplets in the fog evaporate - making the air more humid and leaving the smoke particles to settle out.

Either way, the nasty smoke doesn't enter your lungs. So I think that staying indoors during smog conditions is indeed a good idea. However - for other kinds of air pollution - NOx, SOx, Ozone, Carbon Monoxide, etc - I can't imagine any mechanism that would make the air coming into your home be any cleaner afterwards than before. But in the particular scenario the OP lays out - there is likely to be a pollution 'gradient' where the concentrations are highest in the main part of the road where the traffic flow is (presumably) the highest - gradually tailing off to lower values on the service road - and then to even lower values close to the rear of your home. So while there might be very little (if any) difference between standing just outside your front door versus just inside - I'd expect there to be a measurable difference if you were standing on the grassy median or out in the traffic flow itself. I think a lot depends on what's behind your house. If it were parkland or idyllic unspoiled countryside - the answer would be different than if there were merely another row of houses and an identical road system. In the former case, the pollution 'gradient' would be tailing off as the pollutants were being diluted by the clearer air out in the countryside - in the latter case, there is nowhere for the nasty stuff to go - so there's going to be a gradual levelling out of pollutants between the two sources. In the former case, a lot would also depend on the current and prevailing wind directions. Tcncv's comments about sources of pollutant INSIDE the house is well taken. Certainly things like radon gas (if it's prevelant in your area) which can concentrate inside the building from natural emissions of the ground beneath you. Radon is a radioactive byproduct of natural radiation in certain rock formations (I believe granite is a particularly strong source) - and there have been serious health risks associated with it. If you live in an area where there is radon - you need fans built into the house that ensure a decent air flow to avoid it building up. Outgassing from plastics and (especially in new houses) construction materials is also a source of indoor pollution that you're unlikely to encounter to the same degree outdoors. SteveBaker (talk) 13:26, 29 March 2009 (UTC)[reply]

Now for some concrete suggestions on how to improve air quality inside your home:

1) When you bring in a new item that noticeably smells, such as vinyl, let it sit in the garage or in an unused room (possibly with the window open) until it stops smelling.

2) Time opening of windows for when it is more polluted inside than outside. So, open them after you burn some food, and close them during rush hour.

3) Try to open windows away from outside pollution sources. In your case, the back of your house sounds better, unless there's another pollution source back there. Also open windows in more polluted parts of the house. If the bathroom or kitchen smells, open the windows there, but not in the rest of the house. If you use window fans, point them to exhaust in areas with polluted indoor air and intake in areas with fresh outdoor air.

4) Avoid the use of candles, whenever possible. If you do use candles, extinguish them by leaving a candle snuffer on them, so the smoke particles will settle out of the trapped air, rather than pollute the indoor air.

5) If you have a gas oven/stove which lacks an exhaust fan, limit use to when you can open windows. Beware that many gas stoves have fans which merely filter the exhaust and blow it back into the room. This doesn't remove many of the combustion products, or replace oxygen lost during combustion. An electric oven/stove pollutes less, but you can still get smoke from the food. This is worst for frying and least problematic when boiling water, say as when making hard-boiled eggs. Microwaving foods is generally better than conventional stoves or ovens, although burnt foods can obviously pollute the air regardless of the method of cooking.

6) Be careful when using air filters, as many can make the air quality worse. Electrostatic filters, for example, can produce ozone, while HEPA filters in a humid house can grow mold.

7) Avoid the use of spray-cans indoors. In many cases, a non-spray-can alternative may be available. Instead of hair spray, perhaps a pump can be used, or better yet a mousse or other product applied by hand. Instead of spray-on deodorant, perhaps a roll-on, solid, or gel can be used. Spray paint or lubricants can be applied outside or in a garage. Epoxy, glues, wood stain, and paint should all be applied outside, whenever possible.

8) Buy scent-free detergents and other cleaning products, whenever possible.

9) Limit use of electric space heaters, and run them outside for a few minutes to burn off any accumulated dust when using them for the first time in a while, or whenever you notice a burning smell. StuRat (talk) 17:00, 29 March 2009 (UTC)[reply]

Nutritional Question

So. I went to a nutritionist the other day who suggested that I take a few dietary supplements: calcium, b complex, and omega, in addition to a multi, every day. These are all to be taken with food, and separately, so as not to undermine each's effect. This would mean four meals a day, which doesn't really fit in my schedule. But I've also heard that whenever you eat, your metabolism kicks up--thus the many-meals-a-day dietary suggestion often put out there. My question is what suggestions you guys might have for good foods to snack on--portable, cheap, somewhat filling--that I could turn into impromptu meals throughout the day during which to take my vitamins and which would boost my metabolism. I was thinking maybe of celery, which, as is widely said, has "negative calories" due to how it takes more energy to break down the plant's fibers than is gained from metabolizing them.

My question, though, is whether this will a) effectively kick up my metabolism, since it contains so few calories, and b) whether a substance my body has difficulty digesting will provide the necessary buffer or whatever that the dietary supplement needs to be fully utilized. Would celery work? Bananas? Any other non-fattening suggestions? I'm also trying to lose a little weight, if that hasn't already been made clear.

Thanks a lot, 70.108.188.101 (talk) 03:05, 29 March 2009 (UTC)[reply]

PS, while I'm at it. Protein and working out. If I go lift weights at the gym, and I want to maximize the effect, when should I ingest protein? Before? Immediately after? Does it matter? And will eating directly after be a wasted metabolistic boost, as exercise already boosts one's metabolism temporarily? Thanks again, 70.108.188.101 (talk) 03:05, 29 March 2009 (UTC)[reply]

Please use the search button with regards to the protein question, it has been asked and answered twice before in the last 2-5 months. --Mark PEA (talk) 12:49, 29 March 2009 (UTC)[reply]

To clarify, Mark is referring to the search box/button at the top of the page labeled "Search reference desk archives", not the search box/button in the side bar, which searches the main Wikipedia pages, and doesn't include the Reference Desk archives by default. -- 76.204.102.79 (talk) 17:21, 29 March 2009 (UTC)[reply]

I wouldn't be too worried about taking vitamins and other nutritional supplements with the same meal. You could take some at the beginning of a meal and others at the end, for example, so they interact with each other less. I also don't quite understand why you would take a multi-vitamin and also take things like calcium, which are no doubt already included in the multi-vitamin. Finally, I should mention that vitamin and mineral supplements haven't been shown to be helpful for healthy people with a healthy diet (who aren't suffering from a deficiency). And, if you have an unhealthy diet, improving it would be better than just adding supplements. StuRat (talk) 16:46, 29 March 2009 (UTC)[reply]

Galaxy cluster data

I'm investigating some natural datasets with fractal statistics, and I'd like to include the large-scale structure of the universe. So what I'm looking to create, ultimately is a normalized dataset of points with 3D Cartesian coordinates, such that each point represents a super-cluster, and the whole set is scaled to fit inside the unit cube (or unit ball or something similar). In essence I'm looking for the kind of dataset that would produce this image, or the next one in the series. I don't know precisely what scale I'm looking for (galaxy clusters, or superclusters or what), but somewhere 1000 to 10000 points would be ideal. A set of densities in a grid, rather than points would also be good.

I'm perfectly willing to put in the work and learn the required algorithms to do the coordinate conversions, but at the moment my lack of knowledge about astronomy is making it difficult to find a starting point. Which survey would be the right starting point? What steps would I need to take to get the manageable cube of cartesian points I'm looking for? Can I just make the step from curved space to euclidean geometry like that or is it impossible to represent the universe like that without massive errors? Any help will be appreciated, thanks. risk (talk) 16:29, 29 March 2009 (UTC)[reply]

You might be interested in this article: Large-scale structure in the Universe: Plots from the Updated Catalogue of Radial Velocities of Galaxies and the Southern Redshift Catalogue. This page gives the principle galaxy catalogues. The Wikipedia articles are not very informative, or non-existent on these unfortunately. After that, if you want to work in more detail still, you are looking at working directly from the starfield images. On the question of conversion to cartesian co-ordinates, the distance to the galaxies is calculated from the Hubble redshift which is only valid if our model of the universe's gravitational field equations is valid. SpinningSpark 19:48, 29 March 2009 (UTC)[reply]

The state-of-the-art catalogue would be the Sloan Digital Sky Survey Data Release 7, accessible here. It contains spectroscopic redshifts (essentially distance, as mentioned above) for nearly a million galaxies. It is not whole-sky, hence you'll run into some (probably solvable) problems of placing your cube properly. There are a number of cluster catalogues based on (earlier releases of) the SDSS, although I can't name any names off the top of my head; just use Google or search in ADS. The coordinate transformation is relatively straightforward (there is a complication do to proper motions contributing to some extent to the redshifts - less of a problem if you start from a cluster catalogue). The biggest problem is probably to properly account for the selection function, or incompleteness, of the survey. All in all, not a simple undertaking! --Wrongfilter (talk) 09:34, 30 March 2009 (UTC)[reply]

Attributes or Parameters of Sound

What are all of the attributes or parameters of sound? Because I'm pretty sure there are more than just volume and frequency. And what is the article about the attributes or parameters of sound? --Melab±1 ☎ 17:31, 29 March 2009 (UTC)[reply]

I'm not sure we could list ALL of them, it depends on how detailed you get. Traditionally, musical sounds have three charactaristics: Pitch, Loudness, and Timbre. If converted to a waveform, "Pitch" is analogous to frequency/wavelength; "Loudness" is analogous to amplitude, and "Timbre" is all the little squigly bits that make it different from a simple sine wave. So basically, to answer your question, EVERYTHING not pitch or loudness is considered part of "timbre". You may also want to read the acoustics and sound articles. --Jayron32.talk.contribs 17:57, 29 March 2009 (UTC)[reply]

This may be a different way of looking at it. For a simple sine wave, frequency and volume are all you need to reproduce the sound. For a slightly more complicated sound you could combine two sine waves, with different frequencies and volumes. For this sound, you'd need four parameters (two frequencies and two volumes) to reproduce it. You can get these from the original sound using a Fourier transform.

If you apply this fourier transform to natural sound, you find that it isn't made up of two or three frequencies, but that all frequencies in some range are represented with different volumes. So in this sense, the number of parameters depends on the complexity of the sound wave, and things like white noise have an infinite number of parameters. risk (talk) 18:23, 29 March 2009 (UTC)[reply]

Within some specified frequency range and fidelity (eg that of human hearing), the number of parameters isn't infinite - it's really quite a small number. SteveBaker (talk) 18:31, 29 March 2009 (UTC)[reply]

(ec)

Well, in a sense - amplitude (volume), phase (delay) and frequency (pitch) really are the only parameters. Every sound imaginable can be made by adding together some number of sine waves with specified volume, relative-phase and frequency - and NOTHING else. We can even use mathematical techniques such as Fourier analysis and Wavelets - to figure out what set of frequency/phase/amplitudes are needed to reconstruct any given sound to whatever fidelity is required.

In another sense - there are a literally infinite number of possible wave-shapes and the description of those using English words and without math or science to help requires this huge vocabulary of vague terms that musicians and others have built up over the years.

In a third sense - any waveform of any complexity can be represented to better accuracy than our ears can detect using 40,000 numbers in the range -32,000 to +32,000 for every second that the sound lasts. Each of those numbers is the instantaneous "volume" of the sound - so in that sense, it's just volume - and nothing else.

Things get a bit more complex with spatial audio - stereo, quadrophonic, 3D,etc.

SteveBaker (talk) 18:28, 29 March 2009 (UTC)[reply]

Steve Baker beat me to mentioning the direction. The human nervous system has special pathways to analyze the direction of sound, primarily horizontally, but you also can sense wideband sounds' height or distance to some extent. Another aspect is the "presence" where you can hear the sound effect of a room, the reverberation causes a bathroom, hall, outdoors, carpeted bedroom to all sound different. Graeme Bartlett (talk) 21:11, 29 March 2009 (UTC)[reply]

I thought there must be a term for the sound of a room, thanks for that. The article on reverberation talks about the sound dying out but I can hear it better when it is quiet. I guess there must be low level sound all the time like the seashell effect with a hand over the ear, that's why one can hear what a room is like without any explicit noise. Dmcq (talk) 21:41, 29 March 2009 (UTC)[reply]

Alien Fast and Slow thinkers.

I'm re-reading the scifi book "The Algebraist" by Ian Banks...one of the themes is that some species of alien are 'fast' living/fast-moving/fast-thinking and others are slow. It's thought-provoking to imagine the benefits of being a 'slow' species - one of which is that the speed-of-light limit for interstellar travel is much less of a problem for slow species. Imagine a species that operates at speeds perhaps a million times slower than us. A 1% of lightspeed 400 year trip to the nearest star taking just a few hours in perceived time.

We have a few organisms on Earth who can live for hundreds to maybe a thousand years - but I'm thinking creatures who can move and think. Anyway - I was wondering what the biological (or other) limits there might be for super-slow life forms?

SteveBaker (talk) 18:14, 29 March 2009 (UTC)[reply]

I think a lack of evolutionary adaptation would be one of the main drawbacks on a planet like ours. If death/birth occurs only once in a very long time, then the creatures with shorter cycles will adapt faster to any change in the environment. Any creature that's going to live 10000 years must either be very independent from its surroundings, have a very stable environment, or be capable of adapting by other means than evolution (like modern man), and do so in a way that beats out the fast evolving animals with the short life cycles. Of course at some point a short life cycle is going to have disadvantages as well (it's difficult to grow to 100kg in five days). Despite the evolutionary disadvantage, I can't think of a reason why lifeforms couldn't have (theoretically) infinite life. risk (talk) 18:50, 29 March 2009 (UTC)[reply]

A 400 year spaceflight might be trivial to such a race but, equally, it would take them an inordinately long time to build the spaceship. The ten-year Apollo program, for instance, would take them 10 million years in your example. To get to another star, well, the target might very possibly not be there any more by the time they had built anything. SpinningSpark 20:01, 29 March 2009 (UTC)[reply]

True - but a 'fast' species like ours has problems too. We can build such a device in 1% of a lifetime - but it takes tens of lifetimes to actually get anywhere inside it. For super-slow lifeforms, it still takes 1% of a lifetime to build - but once built, you can go zipping around the galaxy like it was a vacation trip to Vegas. SteveBaker (talk) 21:43, 29 March 2009 (UTC)[reply]

(edit conflict) Another problem is that if a species reproduces, say once every 10000 years on average, the ones that reproduce faster would, well, reproduce faster and would become a larger part of the gene pool, which means that the average speed of reproduction would steadily decrease until there's a significant advantage to taking longer. As for simply moving slower, take an herbivore with no predators, such as a turtle. If it moves half as fast, it gets food half as fast, but, beyond a certain point, it takes more than half as much energy to live, so it wouldn't move slower than that. Most animals either eat meat, which they have to be able to chase down, or have predators, which they have to be able to run away from, so they move much, much faster. It's possible that an animal that's in a completely different circumstance might have a significantly lower optimal speed for a turtle, but if it has any predators or prey, it's going to have to move fast. — DanielLC 20:04, 29 March 2009 (UTC)[reply]

Well yes, if you are talking about lions and gazelles. But even on earth there are an extraordinary variety of environments and solutions. In the arctic, equivalent species tend to live longer and move slower, I understand that crabs have a surprisingly long lifespan in the arctic. Whelks hunt mussels at (forgive the pun) a snail's pace. It must be at least possible, that in alien environments we don't understand populated by lifeforms whose solutions we have no way of knowing, such a slow-moving system prevails. SpinningSpark 20:46, 29 March 2009 (UTC)[reply]

I was thinking that these guys would have to have evolved in a low-energy environment - perhaps in very dim sunlight - where plant growth would have to be really slow and anything that evolved to feed on those plants that lived significantly faster would wipe out the vegetation in short order and then starve to death - and anything that predated on super-slow herbivores would have no need to evolve to be super-fast in order to catch them. Besides, we do have slower-living things (like the Sequoia - which lives for over 2000 years - but doesn't happen to move or think to any noticable degree). I was wondering more about biological limitations - maybe its DNA would decompose or something - erosion of body structures due to wind & rain could be a major problem...that kind of thing. SteveBaker (talk) 21:43, 29 March 2009 (UTC)[reply]

Contrary to SB´s assertion, Sequoyah DID move and think. --Cookatoo.ergo.ZooM (talk) 22:23, 29 March 2009 (UTC)[reply]

There's a whole lot of options in the question of 'fast' living/fast-moving/fast-thinking - each of the three could be slow or fast independently. For instance one could be fast moving with very rapid and extensive reflexes and pre-thought actions and yet be a very slow thinker, or one could think very fast and be stuck in a slow body. Dmcq (talk) 21:16, 29 March 2009 (UTC)[reply]

Freeman Dyson wrote an essay (the title of which I can't remember) about how he thought life could continue as an open-ended universe dwindled away toward heat death. He postulated creatures that lived progressively closer and closer to their (very chilly) ambient temperature, and which ran their body processes very slowly indeed. Perhaps someone can remember more about it (I think it might have been published as part of Infinite in all directions). 87.114.147.43 (talk) 22:15, 29 March 2009 (UTC)[reply]

Dyson's eternal intelligence has the citation: “Time Without End: Physics and Biology in an Open Universe”, Rev. Mod. Phys., 51, 447–460 (1979). Chapter six of Infinite in All Directions contains a summary. —Tamfang (talk) 04:36, 31 March 2009 (UTC)[reply]

Speed of thinking is probably based on chemical processes in the body and the speed of travel of electrochemical nerve impulses. Previous experience with similar thought processes may also play a part. An alien life form may use different chemical processes and that may affect the speed of thought, and perhaps the awareness of time and length of life as well. Life on earth is sometimes said to be carbon based. I once read a science fiction story in which silicon was the basic life chemical. Like carbon, silicon has the ability to form many chemical compounds, and thus may be useful in forming the many chemical compounds life requires. – GlowWorm. —Preceding unsigned comment added by 98.21.108.66 (talk) 22:55, 29 March 2009 (UTC)[reply]

I could picture some kind of plant, which moves extremely slowly, perhaps by growth alone, and yet lives for millions of years, allowing it to migrate great distances in a lifetimes. One case where this might work is in an extremely high gravity environment where something like a moss may be the only thing which can survive. I also had the idea of a single organism on a planet, which never reproduces, but only spreads, over millions of years. StuRat (talk) 04:07, 30 March 2009 (UTC)[reply]

Many intelligence tests and ability tests have a time limit for doing the test. The test originators apparently believe that, as well as the test score, a person who completes more of a test in the allowed time has more ability than a slower person. (A slower person will answer fewer questions, and thus can have fewer correct answers.) I wonder if innate speed of thought, or speed of answering questions in a test, is a valid indication of the ability being tested. Has this ever been investigated? Should a person be allowed as long as he wants to do a test? Is a time limit simply for the convenience of the person adminstering the test? – GlowWorm. —Preceding unsigned comment added by 98.21.104.119 (talk) 09:04, 30 March 2009 (UTC)[reply]

No. For two humans - with identical biochemistry and near-identical morphology - you'd expect them to think at the same rates. If one of them takes longer to do the test then we can conclude that they are not as intelligent. If we ever came across an alien civilisation with thought rates that were significantly slower than ours - yet had made more intellectual achievements than us (albeit in longer amounts of time) then we might have to come up with a new definition of 'intelligence'. But then we don't have a decent definition of that word anyway...so take what you like from that! SteveBaker (talk) 13:49, 30 March 2009 (UTC)[reply]

I don't agree with equating speed of test-taking with intelligence. If one student double-checks his work, for example, that's a good thing, even if neither had a mistake. Or perhaps one takes the time to write his work out very carefully and clearly, while the other only makes illegible scribbles. Thus the first student would make a good scientist or engineer, while the second can only qualify to be a doctor. :-) StuRat (talk) 14:08, 30 March 2009 (UTC)[reply]

As for why they limit time on tests, yes, that is for the convenience of the test givers (and takers). I'd say that time would need to be limited in some way, in any case, but they certainly don't need to limit it to the point where many students are unable to finish. This teaches students that giving quick answers is more important than right answers, which is a very bad thing. The way the standard school day is broken up is one problem. Each class is typically less than an hour long. In such a short time period, even one complex, multi-part question may be too much for a few students to complete. Some schools use a different system, where they have one class before lunch, and another after. This allows more time for a test (as long as they don't triple the test length), but can introduce a new problem. With such a long period students are likely to need bathroom breaks, which could allow them a chance to cheat by talking to each other or looking up things. StuRat (talk) 14:20, 30 March 2009 (UTC)[reply]

Building anything would be a challenge on an earth-like planet, but i suppose life might be easier on a planet with a very calm atmosphere, and no oxygen in the air. You'd still have to worry about structural components wearing out while you were still building. If your house collapsed it would happen so fast you wouldn't be able to perceive it.

That makes me wonder if the laws of physics would be easier or harder to work out. On the one hand, the planets would slide around in the sky in a timescale that lends itself to direct observation, (Earth would orbit every 31 perceived seconds.) but on the other hand your planet would be spinning at a dizzying rate. Ball-drop experiments and the like would also be difficult. How would early slow-creatures work out such early principles? APL (talk) 14:50, 30 March 2009 (UTC)[reply]

I guess we already have that problem though - there are plenty of events that happen too fast for us to measure (try measuring the speed of light with a flashlight, a mirror and a stopwatch!) - and others that happen too slowly (plant growth, continental drift). I imagine there would be a range of phenomena that these hypothetical creatures could use in order to learn about science. To them, continental drift would be so obvious that it would hardly need to be stated - but look how long it took us to figure it out! They could also build quite useful computers using simple mechanical systems - so perhaps they'd have more advanced computers than us. Certainly if they ever did figure out how to make electronic computers - their speeds would be unimaginably fast (to their slowed perceptions at least). SteveBaker (talk) 22:55, 30 March 2009 (UTC)[reply]

Possibility of recovering methane hydrate from seabed

Hello. I have come up with an idea for a business involving methane recovery and refining. As you may be aware of, there are numerous methane reserves under the seabed. There are estimates that the energy content surpasses that of the oil reserves by as much as a factor of two! Methane exists down there as a hydrate. By any means, is it possible that the methane hydrate could be recovered without risk of realeasing all that gas and setting off a climate catastrophe? And is it possible that the methane hydrate recovered could be refined into methane or some other usable fuel? If it does work, please don't run away with my idea and make money for yourself, as it was my idea to start that business. Thanks to all who answer.--Under22Entreprenuer ^discuss 21:21, 29 March 2009 (UTC)[reply]

Unsurprisingly, you are far from the first, or the only, person to have such an idea [4] [5] [6] Nil Einne (talk) 21:40, 29 March 2009 (UTC)[reply]

The problem is two-fold. Firstly that these things exist only in the deepest parts of the ocean - where mining would be exceedingly difficult. Secondly that extracting energy from the stuff produces CO2 - which produces the climate catastrophy you were trying to avoid. Granted, methane is a nastier greenhouse gas than CO2 - but it decomposes in the upper atmosphere after a fairly short amount of time (10 years maybe) - where CO2 stays there pretty much indefinitely. Sadly, this idea is very far from being new...and you're not going to make a fortune from it. SteveBaker (talk) 21:55, 29 March 2009 (UTC)[reply]

Unfortunately... But I have other ideas for businesses.--Under22Entreprenuer (talk) 00:38, 30 March 2009 (UTC)[reply]

See methane hydrate. Hydrates form in ocean sediments at depths (relative to the ocean surface) of approximately 300-700 m, and hence exist on continental shelves. They do not form in the deep ocean at all as methane hydrates are not stable there. As we have learned more about these hydrates it appears that most deposits are probably not economically viable due to concentrations of only a few percent methane by mass relative to sediment. Dragons flight (talk) 22:17, 29 March 2009 (UTC)[reply]

Methane hydrates have already been observed to be melting, so if you want to avoid a climate catastrophe, you should act quickly. Unfortunately, CH₄ hydrates are effectively another fossil fuel, and will release CO₂ into the atmosphere. However, if there's a way of burning it without oxygen, or sequestering the emissions, then it may be a more eco-friendly method. ~A H 1^(TCU) 23:26, 29 March 2009 (UTC)[reply]

If it's not economically viable to extract them, then extrating them to save the planet is potentially a bad idea as you may make the situation worse from all the energy you expend extracting them Nil Einne (talk) 05:16, 30 March 2009 (UTC)[reply]