Wikipedia:Reference desk/Archives/Science/2006 November 6

From Wikipedia, the free encyclopedia

Science desk
< November 5 << Oct | November | Dec >> November 7 >
Welcome to the Wikipedia Science Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.


Contents


[edit] November 6

[edit] How to detect the presence of UV-C (253.7 nm) light?

In my aquarium, I use an ultraviolet sterilizer that uses a germicidal lamp to produce UV-C (253.7 nm) light. (In fact, the pictures of the lamp in the germicidal lamp article are my pictures of this very device.) The theory is that the UV-C light will kill algae, bacteria, and viruses in the water passing through the sterilizer. The assembled device has a viewport through which one can observe the visible light produced by the germicidal lamp and assure oneself that the device is operating.

Now any sensible design would specify a viewport that was made out of a material that was opaque to the (somewhat dangerous) UV-C light, and I have no special reason to doubt the design of this device, but I'd really like to prove that the window is blocking the UV-C before I sit in a darkened room near my aquarium with that very cool mercury glow reflecting off my walls towards me and my darkness-dilated pupils.

Does anyone have any good ideas about how I might prove or disprove the presence of any UV-C light escaping from the viewport? Something I might have that only fluoresces in UV-C and not any near-UV wavelengths? A chemical reaction I might provoke? Would I smell ozone at radiation levels below those that would be otherwise-hazardous to me? Should I see if my skin gets burned ;-)? (Ignore that last suggestion!) Expose an EEPROM to it for hours and see if it gets erased?

Atlant 01:33, 6 November 2006 (UTC) [

D'oh! Perhaps fluorescent lamp phosphors? I'm sure I have some dead lamps around here; I'll test the phosphor and see if near-UV also stimulates it. Any other ideas?
Atlant 01:40, 6 November 2006 (UTC)
Hang on tho. Do normal flourescent lights actually produce UV-C? If not, then how do you know that the phosphors on these lamps will be stimulated by any UV-C?
If you were able to cut out the visible light with a filter, maybe you could then use a photoelectric radiation sensor of some sort. Not sure what sort cos it would have to respond to UV-C. See photoelectric effect. 8-)--Light current 01:50, 6 November 2006 (UTC)
Ah here we are [1]. Does mean shelling out cash though!--Light current 01:53, 6 November 2006 (UTC)
Thanks! But those are also sensitive to near-UV (and probably visible light as well), so I'd also need to obtain a bit of filter glass that was only transparent to UV-C.
Atlant 13:14, 6 November 2006 (UTC)
UV-C will be absorbed by a fairly trivial amount of ordinary glass or plastic (e.g. plexiglass), like the thickness of a playing card, so I doubt you have anything to worry about it. You would not expect an ozone smell or anything like that. In terms of household items, ordinary styrofoam is pretty bright under UV-C, as is the dye used in many things designed to be neon green. I don't know how those would appear under UV-A for contrast though. Dragons flight 02:01, 6 November 2006 (UTC)
I knew ordinary borosilicate (etc.) glass would filter UV-C but I didn't know that (undoped) plastics would also filter it. If that's the case, that's probably the mechanism the device vendor is counting upon; I don't know how thick is the plastic that forms the transparent viewport, but we're certainly talking millimeters and not "playing card" thickness.
Atlant 13:14, 6 November 2006 (UTC)
So am I correct in thinking that ordiary mercury discharge lamps (fluorescent lamps)produce UV C but that it is filtered out by the glass of the tube?--Light current 02:08, 6 November 2006 (UTC)
Yes, normal fluorescent lamps make a large amount of UV-C that is filtered by the glass tube. Dragons flight 02:13, 6 November 2006 (UTC)
Thanks IDKT 8-). So the germicidal one must use a special glass?--Light current 02:15, 6 November 2006 (UTC)
Yeah, fused silica. Dragons flight 02:19, 6 November 2006 (UTC)

(edit conflict)

mercury vapour lamps do, but they are for rather specialist applications. ordinary fluoro tubes do produce UV, but this is wavelength-shifted by the lamp phosphors down into the visible. any residual UV (if any) will be soaked up by the glass envelope. have a look at fluorescent lamp. and with regards to the original question, see if you can get some silica gel F254 from a chemistry contact. a TLC plate made from silica F254 would work also. the dye in the silica lights up bright green under 254 nm light, but not under other (at least 360nm) UV light. Xcomradex 02:23, 6 November 2006 (UTC)
Yes, that's the best description of what becomes of the (mainly) UV-C that's generated within an ordinary fluorescent lamp: most is downconverted to visible light with the remainder absorbed by the glass envelope.
Meanwhile, will ordinary "drying agent" silica gel (You know, the "Do not eat!" stuff) also fluoresce in this fashion or is the F254 specifically doped to do that? I'm sure I have packets of the drying agent variety around the house.
Atlant 13:14, 6 November 2006 (UTC)
no regular silica gel won't do it, the F254 is impregnated with a dye that gives the fluorescence. i'm not sure what the dye is either, i had a quick look on google with no result, and it's not written on the box. but i do see you can get a box of plates on e-bay, but that's a bit of a waste for your purposes. you might get lucky emailing someone friendly at your local uni, you'd only need a small piece of plate (less than 1x1 cm). Xcomradex 21:22, 6 November 2006 (UTC)

Results of initial experiments:

I did some experimentation using a fluorescent/phosphorescent toy which is very strongly pumped by 360 nm UV. Based on some risky experiments done a long time ago in my youth with a similar UV-C source and a similar phosphorescent object, I'm pretty sure that the phosphors in the toy would be about as well-pumped by UV-C as by 360 nm UV.

It was also possible to pump the phosphors (a lot less efficiently) with the bright blue (visible) light from an LED. Then I tried it with the light being emitted by the viewport of the UV sterilizer. This turned out to be about ten times less efficient than the light from the LED. That is, to get an "afterglow" of intensity n, one had to expose the toy to the viewport for about ten times longer than the blue LED. I'd guess that this tracked pretty well with the intensity of the visible light from the viewport versus the intensity of the light from the LED.

I then placed my eyeglasses between the viewport and the toy. (My eyeglasses are treated to absorb most near UV and almost certainly UV-C.). This did not appear to have any effect on the intensity of the derived phosphoresence.

So my initial assessment from both of these experiments would be that there's essentially no UV-C coming out of the viewport; my eyeglasses didn't seem to attenuate any light coming from the viewport (so no UV-C was presen to be attenuated) and the visible intensity of the viewport-provoked phosphorescence seemed to track well with the visible intensity of the blue LED-provoked phosphorescence (so no need for UV-C to boost the phosphorescence).

If I get a chance, I'll still play with the fluorescent lamp phosphor, but I think the question is mostly settled.

Atlant 01:21, 7 November 2006 (UTC)

a well thought-out, resourceful method. good work. Xcomradex 09:56, 7 November 2006 (UTC)

[edit] Finding the taxonomic classification

using wikipedia, what is the quickest way to find the kindom, phylum, class, order, family, genus, and species knowing the common name. —The preceding unsigned comment was added by 68.226.202.104 (talk • contribs) 03:12, November 6, 2006 (UTC).

First try if there is an article on the life form whose title is that common name, by entering it into the search box (see the margin) and pressing Go. For example, if you want to know about gobies, entering "goby" there will bring you to the article Goby. It has a taxonomy box giving the classification. Possibly you are redirected to an article with a different name for the same species or genus. Otherwise, you will see a list of articles in which the search term or components of the search term occur. For example, we have no separate article on Nile bichirs, but if you search for it you will see a link to the article Bichir, which also gives the binomial name and classification of the Nile bichir.  --LambiamTalk 09:52, 6 November 2006 (UTC)
(edit conflict) I hate to state the obvious here, but have you tried typing the common name into the search box, and hit your enter key? Many will have a taxbox with the info you require. See my namesake, Rock pocket mouse, for example. Rockpocket 09:54, 6 November 2006 (UTC)

[edit] Grease + paper = semi-clear?

Could someone explain to me why grease turns paper clearish? I asked on Google Answers but I don't really understand the answer someone gave me. I understand what homegeneous means, but what about the light diffusion part?

The grease soaks into the tiny open spaces in the paper and into the fibers, thus creating a much more homogeneous mass - like glass - in which the light is not diffused as much. It also coats the surface, with the same effect, as does a liquid on the surface of ground glass (glass that diffuses light due to a rough surface produced by abrasion or etching). To some extent, warm wax will produce a similar effect.

[2] Chickenflicker 03:55, 6 November 2006 (UTC)
He's saying that the grease gets absorbed into the fibers and becomes one, which you already understand. Then because it is one, light can pass through more easily. If you look at diffusion, it lists carbon dioxide in soda as an example of diffusion, and I can think of no better way to explain it. When you have a bottle of Sprite, doesn't it look like water? Because the carbon dioxide is dissolved in the liquid. But when you open the bottle, the gas rushes out, and bubbles are formed, and it no longer looks as transparent as water because you have the bubbles blocking the path of light. It's similar to that. However, I don't know why he didn't just say water turns paper clearish too. --Wirbelwindヴィルヴェルヴィント (talk) 05:37, 6 November 2006 (UTC)
Okay, thanks for the explanation. I guess I was kind of wondering how exactly the grease differs from water on paper - it you put a drop of water on a piece of paper it's not going to turn clear, but if you put a drop of grease/lipid on a piece of paper, it will turn clear, and I was wondering what was actually happening there. Chickenflicker 13:08, 6 November 2006 (UTC)
I think you're seeing the result of two effects combining synergistically.
  • The grease is more effective at wetting the fibers of the paper than is the water. So the grease works its way into all the tiny interstices in the fiber, creating a pretty uniform material.
  • I think the grease is probably pretty close in refractive index to that of the cellulose fibers that make up the paper. Because of this, and because the fibers are now fully surrounded by grease owing to wetting, light isn't bent much as it passes through the many fibers of the paper. So not nearly as much light is scattered as was when the paper was fresh and clean.
Science museums often have a cool demo that helps illustrate this sort of thing. They'll have a tank of oil and some glass optics and glass tubes containing liquids suspended above the liquid in the tank. In that position, you can see all the suspended stuff clearly (because it all refracts light). But you can then lower all the hardware into the oil, et voila!, the lens disappears as do most of the glass tubes! It turns out that the oil in the tank has the exact same refractive index as the glass in the lens, the glass of the tubes, and the liquid in most of the tubes. So they no longer bend light and can no longer be seen! Usually, one tube is filled with a different liquid so it stays visible even when immersed in the oil bath.
Atlant 13:24, 6 November 2006 (UTC)

[edit] black body radiation

In the black body radiation article there is a section called "relation between a planet and its star" where it states that "the temperature of the Earth only depends on the surface temperature of the Sun, the radius of the Sun, and the distance between the Earth and the Sun." What?! I thought the atmosphere had something to do with it?? what's global warming?

How they use the equation is to start with the temp of the earth and backwards evaluate to come up with the temperature of the sun within 3%, pretty impressive, except that if I plug in the average temp of the moon which is 250k, i get a result about 14% off. What am i missing? is it something to do with the assumptions in the article that:

1) The Sun and the Earth both radiate as spherical black bodies in thermal equilibrium with themselves.

2) The Earth absorbs all the solar energy that it intercepts from the Sun.

I don't quite understand the 1st one, is the moon not in thermal equilibrium with itself? and if it isn't are they trying to say the Earth is? So it wasn't where there was an ice age? Or if we have some more global warming? So they're telling us the earth is within 3% of perfect thermal equilibrium?? Why does that doesn't sound like coincidence? Planck was obviously smarter then me, so what am I not getting?? Vespine 06:00, 6 November 2006 (UTC)

Okay, basically what we need to recognise here is that all the heat on the Earth came from the sun. Let's pretend, for a minute, that the Earth is a nonreflective ball with no atmosphere. Every body radiates heat, and if it doesn't produce heat itself, that radiation occurs at a rate that is proportional only to the body's surface area and temperature (assuming it has uniform temperature). So the sun radiates heat which warms the Earth, but the Earth radiates heat into space, cooling itself down again. Suppose the Earth was very cold. Then it wouldn't radiate much heat, but it would still absorb heat from the sun (and how much it absorbs is dependent upon the Earth/Sun factors you described above). So the Earth would warm up. But as it got warmer, it would radiate heat faster. Conversely, if we imagine the Earth was very hot, then it would radiate heat much faster than it absorbed it, and would cool down. Eventually it would reach thermal equilibrium, where it absorbs as much heat from the sun as it radiates away, and the temperature would remain constant.
Of course, the Earth is a lot more complicated than than a nonreflective ball with no atmosphere. Parts of it are covered with ice, which reflects a lot of sublight rather than absorbing. Parts of it are covered with water, which also reflects sunlight, but there's more water on some sides of the Earth than on others. Lots of it is covered with water vapour and other greenhouse gases, which insulates it and prevents it from radiating heat (and global warming is caused by increases in these blanketing gases). The Earth most certainly does not have a uniform temperature. On top of all this, its atmosphere and oceans are mobile, so they can carry heat around the place in shifting patterns. The situation is extremely complicated, which is why creating a model for it is so hard (and why it's so incredibly that we can predict the weather three whole days in advance with pretty decent accuracy).
I'm not sure what happened to your moon calculations, but hopefully I've given you some idea as to all the different factors that influence things. Maelin (Talk | Contribs) 09:05, 6 November 2006 (UTC)
But also, all the heat doesn't come from the sun. Compressive and rotational (frictional) heating are also present. --Tbeatty 14:43, 6 November 2006 (UTC)

They do make some dubious assumptions, I agree. Not all heat comes from the Sun, there is also radioactive decay on Earth, gravitational/tidal heat generated from the Moon, and heat left over from planet formation. This last one means that the Earth isn't quite in thermal equilibrium, either, but the core is slowly cooling (around 100 degrees per billion years, I believe). The amount of heat the Earth radiates back into space also varies by type of surface, time of year, and many other factors. StuRat 16:07, 6 November 2006 (UTC)

Maybe the white moondust is more reflective (and therefore less of a black body) than Earth's brown/green land and blue oceans. Also note that the Sun isn't the Moon's only light source; Earth is quite bright when seen from the Moon. --Bowlhover 17:20, 6 November 2006 (UTC)
Also note the beginning of the blackbody article, which states that the object has perfect absorption and no reflectivity - the Earth is far from that (I could be totally off, but I think Earth's reflectivity is somewhere around 30%). The Sun is a closer approximation to a blackbody than a planet, which could be a factor in why the solar estimation is closer (or at the very least, the blackbody contributions dominate the emissions of the Sun).
All I seem to be getting here is people kinda agreeing with me, that the equation seems unlikely since there are SO many different factors at work making the situation much more complex then the seemingly simple equation offered in the article.. Well if that was the case, how come the result of the equation to work out the temperature of the sun is witin 3% of the most accurate readings we have ever made? Vespine 21:19, 7 November 2006 (UTC)
The Sun is much closer to an ideal blackbody than a somewhat reflective hunk of rock with an atmosphere. Not entirely sure why that is - it might be related to the Sun's rather elementary/primordial composition, since I think most gases tend to radiate like blackbodies.

[edit] Organelles

What is an organelle found in all cells? I did some research, and all the organelles as far as I found weren't found in all prokaryotes.

tried organelle? you aren't spoiled for choice in so far as universal organelles, since bacteria don't have internal lipid compartments. Xcomradex 06:49, 6 November 2006 (UTC)

How about ribosomes? --Bowlhover 17:00, 6 November 2006 (UTC)

[edit] Home for Unwanted Scholarships

I've been trying to find scholarships online (to be clearer, non-college-specific, non-merit, -need, -disability, or -minority-based, etc) and the biggest problem with the system, if I may say so, seems to be that those I can find have countless applicants already. FastWeb, Scholarships.com, and so on do provide quite a few (a few million dollars worth allegedly), but I think my chances of winning one, especially given my deplorable lack of talent in essay writing, are to put it mildly, abysmal. I dislike lotteries on principle, and I especially dislike ones where the bell curve is conspiring to steal what little chance I do have. I'm not afraid of grinding through application after application if there's a fair chance I'll get some sort of return, but with the number of college entrants clamoring for free money nationwide, I'm pretty sure there isn't. As I understand it, though, there are countless scholarships floating around with few to no applicants, because nobody's ever heard of them and they can't (obviously) afford to advertise much. They just catch as catch can. My question is, then, does anyone have an idea how I could track them down? Black Carrot 06:54, 6 November 2006 (UTC)

My experience is more with non-profits looking for grants and such, but generally speaking, you need to figure out what makes you unique. The more uniquely that you satisfy the requirements of the scholarship, the greater the chance you will recieve it. Start with where you live (your hometown for instance, may have a scholarship for people just from that town), your heritage is good (are you 1/2 norwiegian 1/2 american indian, maybe there is a scholarship just for you) your interests plus other facts (jewish looking to study agriculture? irish-american interested in communications? a woman from Minnesota who wants to study biology?), also your immediate family (child of person whose a teacher? or a metalworker?). Then google for organizations concerned with promoting whatever the thing is -- many organizations offer scholarships of some kind to students who fit their interests, and many foundations are legally bound to pay out money only in ways that satisfies someone's legacy and a scholarship can often fit the bill. Be proactive, contact them. Dina 03:16, 7 November 2006 (UTC)
Thank you for answering. I appreciate it.
The difficulty, see, is that I've done that. Every one of those steps. I could list all the ways that I'm not unique, but people tend to get upset when I do (I'm not sure why), so just trust me. If I could plausibly claim I was any form of minority, I'd be all over it. But I'm not. Luckily, I'm good enough academically for merit scholarships, and the college I'm going to is generous. I'm not complaining. I'm pretty sure, though, that there are scholarships available that have nothing to do with "quality" or "uniqueness" or "need", but rather with the appearance of generosity - that is, they want to give away X amount of money to whatever student wants it, because that's what benevolent businesses do. Coke, for example, or Target. I would me more than happy to oblige them, but I can't find any where the line is less than a mile long. Other people with similar desires are watering down my options. Black Carrot 04:48, 7 November 2006 (UTC)
I thought you said you didn't feel you could win a scholarship on merit, now you can? In any case, while various businesses do offer scholarships, they don't tend to do it randomly or just because you asked and n one has X amount of money to give to wahtever student wants it (because if they did they'd soon go bankcrupt). Also rather then thinking about which ways you're not unique, just think about what you are. Who are you parents and grandparents. What do/did they do? What do you want to study? Where did you grow up? Etc. Don't worry aboout whether this is unique or not Nil Einne 11:31, 7 November 2006 (UTC)
I'm sorry, I could have been clearer on that. I'm good at math, not so much essays, at least according to most of my English teachers. I got the merit scholarship through the SAT National Merit organization. And I realize most people don't get this, so it's probably my fault, but I'm not complaining, you see, and I don't feel bad about myself, I just recognize that there's some things I don't have access to, because the requirements in no way apply to me. There are in fact very few that do, which I know because I've looked for them already. However, there are quite a few that have no requirements at all (except that I be in college and passing), so what's the matter with trying to get them? There just aren't enough of these on FastWeb and all to go around, there being many many people who can satisfy those criteria, so I'm widening my search. Black Carrot 04:16, 9 November 2006 (UTC)

[edit] old history physics

Friction. Little men pushing against an object to slow it down, then thay get squashed and the blood make's it easy to push. when you look for them thay go invisable? i need help i hurd this at school and was wornding if any one could help me —The preceding unsigned comment was added by 60.226.206.134 (talk • contribs) 10:03, November 6, 2006 (UTC).

Our article Friction does not mention invisible squashed little men. Perhaps they have been squashed so badly that you can't see them anymore. Could they have been fairies, or perhaps mosquitoes? It would be good to know that no animals have been harmed in scientific experiments to determine coefficients of friction, unlike poor Schrödinger's cat in determining the half-life of radioactive materials.  --LambiamTalk 11:48, 6 November 2006 (UTC)
Sounds like the legend of the Juggernaut, except that had wheels. Edison 14:58, 6 November 2006 (UTC)
If we guess that this ledgend has a basis in reality, it may be observation of this difference between kinetic and static friction. Static friction opposes motion when the object is not moving up to some critical level of force. Once sliding, however, the force opposing motion is generally less than that critical level of force. In other words, it takes a greater force to accelerate something from rest than it does to accelerate it once moving. This, I think, aptly describes the situation of little men you describe. If this is how your teacher explained it, I'm sorry. The analogy s/he used is confusing; there are no little men. --TeaDrinker 00:28, 7 November 2006 (UTC)
BTW, I do hope your teacher isn't actually a physics or science teacher...? P.S. CPE-60-226-206-134.sa.bigpond.net.au Australians aye, need I say more? :-P Nil Einne 11:26, 7 November 2006 (UTC)

[edit] Kinsey Reports

Some conservative sites allege that Kinsey's data on babies and children could only come from actual observation of sexual abuse so I must ask HOW exactly did Kinsey find his data???

Second, conservative sites also allege that Kinsey was a eugenicist. is this true?

—The preceding unsigned comment was added by 66.177.207.173 (talk • contribs) 10:25, November 6, 2006 (UTC).

Concerning the first allegation, our article Alfred Kinsey says this: The Kinsey Institute maintains that Kinsey never had any sexual interaction with children, nor did he employ others to do so, and that he always interviewed children in the presence of their parents. As to the second, I've never heard this allegation; do the detractors of Kinsey offer any evidence for this (in which case you should be able to examine this for yourself), or is it completely unsubstantiated (in which case dismissing it would seem a good idea)? Eugenics covers a broad spectrum of positions, some of which are pretty bad, while some others are quite reasonable, such as advocating screening for Tay-Sachs disease.  --LambiamTalk 11:38, 6 November 2006 (UTC)

This site has a lot of allegations. [3]

I didn't see any eugenics allegations there, but there are some on Judith A. Reisman's website, all of which appear to be derived from one biography (James H. Jones, Alfred C. Kinsey: A Life). I don't have access to the book and can't examine this further.  --LambiamTalk 12:58, 6 November 2006 (UTC)
Eugenics can range from just thinking that the wrong people are reproducing to actually wanting to do something nasty about it. Just labeling someone a "eugenicist" is a tar brush without much meaning unless details are given about what they actually believed. --Fastfission 13:27, 6 November 2006 (UTC)

Eugenics in the 1920s and 1930s in the US was a very conservative political attitude, primarily concerned with ways of keeping the economically or ethnically or racially undesirable from having so many children in the years before reliable birth control methods. Many American scientists supported the movement. Ironically, today's conservative critics of Kinsey would have found most of the attitudes of the movement quite congenial. alteripse 14:05, 6 November 2006 (UTC)

The "Conservative vs. Liberal" distinctions of today do not map well to early 20th century religion, politics and science. Science, in the form of early 2oth century evolution proponents, supported eugenics with its inherent racial superiority notions and its forced sterilization of the "lesser races." George Hunter, who wrote the Civic Biology textbook that John Scopes had his high school class read, leading to the Scopes trial, in the 1920's, was an evolution theory proponent. Hunter was an outspoken eugenicist, who said that caucasians of northern Europe and north America represented the highest development to date of humanity, and urged humanity would benefit if lesser races (brown and black people) did not reproduce. William Jennings Bryan, the Bible thumping opponent of evolution, was opposed to evolution largely because he said it could lead to racial superiority notions and genocide. Hitler expressed his admiration for the 20th century U.S. eugenics movement. Yet in the Scopes trial, Bryan (very conservsative) lined up against leading east coast scientists and Clarence Darrow, ultra liberal attorney. Edison 15:08, 6 November 2006 (UTC)
The notion of eliminating genetically inherited diseases by eugenics sounds like a good idea to me. However, perhaps modern science will allow us to change the bad genes directly, so eugenics is no longer needed. StuRat 15:29, 6 November 2006 (UTC)
Your not the only one but it is somewhat controversial because what's a disease? Is deafness a disease (note that in some people have chosen to have a child who is deaf)? What about skin colour? Or homosexuality? I personally agree with you BTW, but I can understand why the concept is of great concern to many even those who aren't convinced we're destroying God's work Nil Einne 16:02, 6 November 2006 (UTC)
There could be some room for argument on some of those, but who would argue that inherited breast cancer is a good thing ? I think those who argue deafness isn't a disorder are nuts, too. StuRat 23:00, 6 November 2006 (UTC)
Minor point — Edison was exactly correct, except for labeling Bryan as "very conservative." As a Progressive, he'd map better as a liberal over a long career. He erred in equating Social Darwinism with Evolution. Edison was quite right in that Bryan's real arguement was with those who read "survival of the fittest" as "might makes right." Too bad that nobody ever straightened him out on that point. B00P 06:48, 7 November 2006 (UTC)
Probably because almost all Darwinians of that period did believe that. It was no mistake, in its time, whatever one thinks of evolution today (which is interpretted very differently — remember that the Scopes Trial took place a decade before the Modern Synthesis got rolling!). --Fastfission 04:06, 8 November 2006 (UTC)

I'd much rather people here address the allegations regarding the data on the number of "orgasms" in Kinsey's tables, attributed to children from infancy to puberty. It scares me to think this data could be derived from actual rape, I would just like to know HOW he accomplished finding this data from "hearing personal stories".

Sorry, I assume we all ignored it because the allegation was too stupid on its face to take seriously; child rape is the moral panic of this decade and lots of people cannot talk sensibly about it. Why would someone "rape children" and claim in a scientific paper to have counted orgasms? If he interviewed children and reported that they described having experienced an average of 1.4 broken bones apiece, would you accuse him of breaking their bones? Don't listen to those people; they have nothing intelligent to say. alteripse 10:41, 7 November 2006 (UTC)
The characterization of eugenics as "very conservative" is incorrect. Eugenics of the 1920s and 1930s was thought of as "progressive" and was embraced by people all over the "left wing" (including socialists) as well as conservative elements. "Progressive" aspects of eugenics included its championing of science, its desire to use enlightened governance to effect social change, its rejection of clerical authority over reproduction, and its fundamental vision that the human race was, genetically, a plastic thing which could be remade. It was an approach which appealed to many different political groups for different reasons; the only group which very consistently rejected eugenics was the Catholic Church. --Fastfission 04:06, 8 November 2006 (UTC)

[edit] Ice age?

Someone told me that the pentagon was interested in the results of a report about an upcoming ice age. The thermohaline conveyor is supposedly going to stop, and create another ice age. The person who told me heard this on the radio, so they didn't get the name of the report. I also saw something about this on The Science Channel. I'd like the name of the report if possible. Thank you! | AndonicO Talk 11:48, 6 November 2006 (UTC)

See Shutdown of thermohaline circulation.  --LambiamTalk 11:52, 6 November 2006 (UTC)

[edit] algea inhibitions test.

what is the perpose of the algae inhibitions test in toxicology?

To test for the presence of toxic materials, or at least those that are toxic to algae, which is ecologically undesirable.  --LambiamTalk 20:50, 6 November 2006 (UTC)

Does algae become less inhibited when soaked in alcohol ? StuRat 04:51, 7 November 2006 (UTC)

I once noticed a leech moving about in a rather drunken fashion after I poored alcohol over it to make it let go. Not sure if it was less inhibited and if alcohol would have the same effect on algae, though. :) DirkvdM 05:23, 9 November 2006 (UTC)

[edit] Chemistry : Solution question

When a solution forms where do the molecules or ions of the solute go?

They are dissolved into the solvent. For example, salt + water -> saltwater. StuRat 15:20, 6 November 2006 (UTC)
For a good visualization of this, see this website. --Cody.Pope 01:47, 7 November 2006 (UTC)

[edit] Chemistry: lollipops

Why do candy lollipops sometimes turn sugary?

Of course, they always contain approximately the same proportion of sugar. Do you mean to ask why the sugar sometimes crystallizes ? StuRat 15:17, 6 November 2006 (UTC)

Sugars and lots of other stuff turn goopy from the humidity. This question always crops up. See Hygroscopy. --Zeizmic 16:24, 6 November 2006 (UTC)

This happens to pretty much all candy. When I was in the Marines, our MREs were very old. Very, very old. The M&Ms had lost all the sugar from the inside and had a white-fuzzy appearance. It was sweet and tasked pretty much like an M&M, but it looked like it was covered with some kind of fungus. --Kainaw (talk) 22:10, 6 November 2006 (UTC)
MRE = Meals Regurgitated Eagerly. StuRat 22:39, 6 November 2006 (UTC)
MRE: Meals Rejected by Ethiopians. Xcomradex 09:46, 7 November 2006 (UTC)
"Some of the early MRE entrées were not very palatable, earning them the nicknames "Mr. E" (mystery), "Meals Rejected by Everyone", "Meals Rejected by the Enemy", "Materials Resembling Edibles", "Meals Refusing to Excrete", and even "Meals Rejected by Ethiopians" (in reference to a country that was gripped by famine at the time). Some meals got their own nicknames. For example, the frankfurters, which came sealed in pouches of four, were referred to as "the four fingers of death". Although quality has improved over the years, many of the nicknames have stuck. MREs were often called "Three Lies" - it's not a Meal, it's not Ready, and you can't Eat it." --Russoc4 14:41, 9 November 2006 (UTC)

[edit] Remote unlocking

I received this mail:

Subject: Have you locked your keys in the car? Does your car have remote keys at Home?

If you lock your keys in the car and the spare keys are at home, call someone at home on their cell phone from your cell phone. Hold your cell phone about a foot from your car door and have the person at your home press the unlock button, holding it near the mobile phone on their end. Your car will unlock. Saves someone from having to drive your keys to you. Distance is no object. You could be hundreds of miles away, and if you can reach someone who has the other "remote" for your car, you can unlock the doors (or the trunk).

I tried it and it didn't work. This was my reasoning:

The remote uses radio frequency signals (according to wikipedia here). The RF signals are not picked up by the mobile (The mic in the mobile picks only the audio signals and then converts them to RF). When you keep the remote near the mobile and press unlock, the remote generates the radio freq signals which are plainly ignored by the mobile handset. Am I right in this?

I tested this with two Nokia handsets in the same area. Is there any possibility that this experiment works (may be with any other handsets?). Has anyone really tried and succeeded ? -- Wikicheng 14:46, 6 November 2006 (UTC)

I agree. Perhaps there is an automatic unlock system somewhere that uses sound, but I haven't seen it. StuRat 15:15, 6 November 2006 (UTC)
There is no way this would work. This link should explain why [4] and also offers an explaination for how it may have started Nil Einne 15:21, 6 November 2006 (UTC)

If what this chain claims is true, then thieves could follow you to work, break into your car after you've exited it, call their accomplice back at your house and 'beam' your garage opener through the phone, giving them access to your home (if you have an attached garage). What stops the thief from just taking the remote back to your house? This is beyond ignorant. I would suspect this rumor got it's start when answering machines featured remote access keyfobs based on sound, but which people assumed to be RF. I can't get over how comical it would be to see someone putting their phone up to their car door and yelling 'press it now'... --Jmeden2000 15:47, 6 November 2006 (UTC)

The example is a bit silly but I guess they know you're at work & and they don't have to spend time taking the opener back to your home. For example, if they stole it before you left you might realise and if they stole it from work, they'd have to spend sometime taking it back and they'd have to have some other person watching you at work to make sure you didn't discover them. With this technique they simply need on person at your work. Nil Einne 15:51, 6 November 2006 (UTC)

I wondered if the remote of the cars used either infrasonic or ultrasonic sound waves, in which case, it might have possibly worked. Thanks for the link Nil Einne. -- Wikicheng 18:05, 6 November 2006 (UTC)

Telephones won't transmit infrasonics or ultrasonics either. The telephone passband is pretty much limited to 300-3000 Hz. This urban legend is and always has been a crock.
Atlant 19:43, 6 November 2006 (UTC)
Depends on the filters the phone co uses. THe wires themsleves are quite broadband. Think ADSL!--Light current 14:19, 7 November 2006 (UTC)
That would have been true back in the bad old days of analogue transmission, but today, everything but "the last mile" is T1/E1 carrier or its equivalent, and that has a Nyquist frequency of 4KHz. Heck, in our neighborhood, even the last mile is digital; it's only the last thousand feet or so from the area concentrator that's analogue. Cell phones, especially digital cell phones, also use the same basic techniques (along with a whole lot of digital compression).
Atlant 16:21, 7 November 2006 (UTC)
Yes of course Im only talking about the local loop. THe speech wil be LPFd with a very sharp rolloff in the CO before digitising and hence this is the limiting factor. Previously filtering was used to bandlimit the signals before generating groups supergroups etc.. but Im sure you know all that 8-)--Light current 16:33, 7 November 2006 (UTC)
As an EE major, it amuses me. I reminds me of the "Use your CRT monitor as a camera" and "Hackers can turn your computer into a bomb!" --Wirbelwindヴィルヴェルヴィント (talk) 00:58, 7 November 2006 (UTC)

[edit] Importance of Polar Ice Caps

I'm currently doing an assignment on Polar Ice Caps, and I stumbled upon a question that I can't seem to find the answer to. Could yyou possibly tell me 5 reasons why polar ice caps are important? Thank you very much208.108.170.5 16:47, 6 November 2006 (UTC)Elsie Greer

Perhaps look at the article on Ice caps for inspiration? —Daniel (‽) 18:53, 6 November 2006 (UTC)
I'll give you 2
  • They keep Elsie Greer alive so s/he can pester us about homework questions even tho it says quite clear at the top DO YOUR OWN HOMEWORK
  • They keep Elsie Greer alive so s/he can pass an assignment without bothering to do any work
Oh wait, these reasons aren't important, indeed we'd much rather they didn't do that Nil Einne 11:22, 7 November 2006 (UTC)
  • Elsie, Nil was a bit harsh, but he/she is right. The top of the page says no homework questions and you gave no indication you did any research to solve it yourself. Think about people in the Netherlands like me. I'm quite happy those polar ice caps haven't melted yet. And I'm pretty sure a lot of British people are too. Can you think of any particular reason why people in those countries feel more strongly about this? I give you a hint, my life depends on it... - Mgm|(talk) 11:25, 8 November 2006 (UTC)

[edit] Simple harmonic motion

This is kind of a homework question, but I've done as much as I can (not very) so I'm hoping someone can tell me how to go about it.

Show that if the motion of a body is described by the relationship

x = A1sin(ωt) + A2cos(ωt)

the body moves with simple harmonic motion. Derive expressions for a)the amplitude, b)the maximum velocity and c)the phase angle in terms of the constants A1 and A2.

I've differentiated twice to show that it's simple harmonic motion, but I don't know where to go from there. I guess the next step is to put it into the form x = Asin(ωt + φ), but I don't know how to do that.

Whoops, forgot to sign 80.169.64.22 17:49, 6 November 2006 (UTC)

Take a look at the first formula under List of trigonometric identities#Angle sum and difference identities. You should apply it "backwards", that is, start from where you want to be (Asin(ωt + φ)), apply the identity, and match the result with where you come from (A1sin(ωt) + A2cos(ωt)). To figure out φ, think tan.  --LambiamTalk 21:05, 6 November 2006 (UTC)

Thanks, that really helped; I've got it now. 80.169.64.22 17:25, 7 November 2006 (UTC)

[edit] Scientific papers on the recently-discovered connection between psoriasis and heart disease

There's been stuff in the news on this issue lately. I'm looking thru google myself, but does anyone have a link to an online report, paper, article, study, etc that they can recommend? News items are fine, but scientific/medical papers are better. Thanks in advance! Anchoress 20:25, 6 November 2006 (UTC)

Perhaps you’re referring to the recent JAMA article? Gelfand, Neimann, et al. “Risk of Myocardial Infarction in Patients With Psoriasis.” Journal of the American Medical Association. October 11, 2006;296:1735–1741. — Knowledge Seeker দ 21:37, 6 November 2006 (UTC)
The link between the two sounds a bit flaky, to me. StuRat 22:03, 6 November 2006 (UTC)
very flaky. there are basically saying they had one more heart attack in the severe group than expected for a overall 2% rate. i don't think this constitutes a link at all. Xcomradex 23:12, 6 November 2006 (UTC)
Bad puns aside, I think that the above post is missing the person-years conversion. Seems like an interesting link which has a plausible biologic explanation. Certainly requires more exploration (they don't seem to have controlled for family history), but as an initial finding it is intriguing. InvictaHOG 23:23, 6 November 2006 (UTC)
StuRat and Xcomradex, I think you are underestimating the degree of linkage. This study suggested that, for instance, a 30-year-old patient with severe psoriasis would have a 2–5-fold risk of havine a myocardial infarction. As with InvictaHOG, I agree that there is a plausible physiologic mechanism to explain such a link. However, I also agree that naturally this area of research is still in the early stages, though I wouldn’t be surprised if we find more studies confirming this link. — Knowledge Seeker দ 23:30, 6 November 2006 (UTC)
That's perfect, KS, thank you. Any others? Anchoress 23:19, 6 November 2006 (UTC)
You’re welcome. I’m afraid that’s the only study I’ve read recently concerning psoriasis and MI, though perhaps others are aware of additional studies. — Knowledge Seeker দ 23:30, 6 November 2006 (UTC)

[edit] If humans had evolved from a solely carnivorous species?

In what was would our society be different now? --84.66.186.4 21:25, 6 November 2006 (UTC)

  • It would be a man-eat-dog world. --jpgordon∇∆∇∆ 21:33, 6 November 2006 (UTC)
    Oh god, thats terrible, but I still laughed, hehe. Philc TECI 22:45, 6 November 2006 (UTC)

Umm.. We wouldn't have society if humans couldn't eat things besides meat. It is the human ability to cultivate crops that create a surplus of food that allowed us, thousands of years ago, to create a society and culture that was independent of the struggle for food. Check out the book, Guns, Germs, and Steel if you want to learn more. G.bargsnaffle 22:18, 6 November 2006 (UTC)

People would just do herding exclusively, instead of farming. Eventually you would still get the same land ownership with fences and towns, cities, civilization. StuRat 22:33, 6 November 2006 (UTC)
The thing is being at the top of the food chain is incredibly inefficient so it's plausible we would not have had a surplus of food. Plus it's also (IMHO) a lot more difficult to do so it's less likely a civilisation would ever develop it if they haven't developed farming first Nil Einne 11:12, 7 November 2006 (UTC)
There is still some debate whether it was really a surplus of food. Some anthropologists argue that the advantage of agriculture was not so much the higher food production but the better predicatbility. If you live in a temperate climate and grow diverse crop you can rely on getting a decent harvest for hard work while hunting is always very dependen on luck. But more importantly: A hunter-gatherer tribe is forced to move around to follow the game, i.e. to live as nomads. Farmers, on the other hand, are required to settle down. And as they stay put anyway they can build stuff, amass tools and wealth and get a big household with lots of stuff which would be too bulky to move around. This intensifies the differences in power and status: we have rich and poor people. Also, population density increases and people interact with more people. Both will make it necessary to ponder on rules and this results in "civilisation". But don't forget that the insticts, i.e. the dynamics of our emotions that still govern our behavior, have evolved i our hunter-gatherer past. Agriculture probably didn't change too much in this setup. To recommend another book: Steven Pinker's How the mind works. Simon A. 22:31, 6 November 2006 (UTC)
There has been much discussion over the role of diet in human evolution. There is some evidence suggesting that our versatile diet played a major role in the evolution of intelligence. Were circumstances different, it is quite plausible that primates would not have developed the degree of intelligence that humans have, and they would simply be a carnivorous primate, or (more likely) would have gone extinct. Herding is far less likely to promote the development of a civilization, as it does not require the division of labor that irrigation and such do, and herds can be moved in response to changing environmental conditions whereas crops cannot. But beyond that, I do not believe a solely carnivorous species, given the circumstances and conditions on Earth in the last tnes of millions of years, would have developed intelligence to a degree we would recognize them as human. That does not mean, of course, that intelligent carnivores could not evolve elsewhere on Earth or on other planets. — Knowledge Seeker দ 23:23, 6 November 2006 (UTC)
Why doesn't herding lead to a division of labor ? I picture some doing herding, some finding lost animals, some building fences, some doing the milking, some assisting with calving, some doing the slaughtering, some doing the cooking, some doing the trading, some hunting predators, some finding watering holes and salt licks, some scouting new pastures, some building barns, etc. In addition, you would still have all the normal things having nothing to do with herding, like building houses, sewing clothes, digging wells, building schools and churches, building military fortifications, constructing weapons, building roads and bridges, etc. StuRat 03:52, 7 November 2006 (UTC)
Please be aware that there may be carnivorous species somewhere out there reading this whose intelligence and technology are far beyond ours, so do not make disparaging remarks. Edison 00:37, 7 November 2006 (UTC)
Your comment seems placed to respond to mine, yet it suggests that I was not aware of the possibility of extraterrestrial intelligent carnivores when of course that is discussed in my last sentence, and it also refers to disparaging remarks which I was not aware I made. Please clarify which remarks you found disparaging. — Knowledge Seeker দ 01:40, 7 November 2006 (UTC)
Would I be right in thinking that an intelligent race of carnivores would be far more likely to be warlike/agressive? The Predators spring to mind as a technologically-advanced species that evolved from a carnivorous ancestor. According to one of the books, while they have an advanced civilization, all their scientific effort is directed towards finding better ways of waging war, with the general standard of living amongst the 'Predators in the street' being pretty meagre. --Kurt Shaped Box 00:56, 7 November 2006 (UTC)
Intelligent carnivores exist here on planet earth right now. They're called dolphins. They don't seem terrible war like to me though. But then again, I've never seen them build anything either. --Cody.Pope 01:00, 7 November 2006 (UTC). See also Cetacean intelligence. --Cody.Pope 01:03, 7 November 2006 (UTC)
Dolphins can't hold guns. --Kurt Shaped Box 01:26, 7 November 2006 (UTC)
(ec) but when they evolve opposable thumbs, we're done for. Xcomradex 01:33, 7 November 2006 (UTC)
That's only cause of their flippers!! Plus, I do believe that the US spends more money on the military than any other facet of government and/or research. So, we're already there. --Cody.Pope 01:31, 7 November 2006 (UTC)
Don't the US (and possible other governments) use dolphins for military purposes? Indeed I seem to remember there were some armed dolphins who er escaped during Hurricane Katrina... Nil Einne 11:10, 7 November 2006 (UTC)
Indeed.

[edit] Freshly boiled water and tea

The serving instructions on my Organic Fairtrade pure china citrus green tea box state: Pour freshly boiled water over the teabag (re-boiled water loses the oxygen content required to bring out the true flavour)...

This stuff about the oxygen sounds like a load of hocus-pocus to me (and have looked at the tea article) but can anyone explain why it is or isn't true?Mmoneypenny 21:52, 6 November 2006 (UTC)

Water does have oxygen in it. The oxygen can be depleted. If you've ever won a goldfish as a school carnival, you probably know about this already. The fish consumes the oxygen in a day or two. Then, it leaps out of the bowl in an attempt to gasp for more oxygen. That is why you need one of those little are pumps to add oxygen to the fishbowl. Similarly, when you boil water the trapped air bubbles out. When it cools, air starts to seep back in - very slowly. So, reboiling water will produce hot water with less oxygen because it has been boiled twice. The end result is tea that tastes old. And, I assume you wonder if there is high-end tea made with heavily oxygenated water. Yes. Coffee too. You will normally find it near an "O-bar" where you can also buy scented oxygen masks to breath extra oxygen while drinking your overpriced high-O tea. --Kainaw (talk) 22:02, 6 November 2006 (UTC)
Thanks for the swift reply. I appreciate that water contains dissolved oxygen and that boiling liberates much of it. But does making tea with reboiled water really make 'tea that tastes old'? Does oxygen really bring out more flavour? Are my taste buds just not good enough to tell the difference? Mmoneypenny 22:11, 6 November 2006 (UTC)
There you get into the realm of opinion. I suspect they are just being silly, but then, I don't believe bottled water is a magical health potion, either. StuRat 22:27, 6 November 2006 (UTC)
As an experiment, I boiled my goldfish to see if it depleted the oxygen faster. He failed to survive in what I can only extrapolate as a lack of oxygen. :) (just kidding). Tbeatty 23:25, 6 November 2006 (UTC)
It seems likely that the amout of dissolved gases (air not only contains oxygen after all) influences the taste. Whether it is better or worse with less air is maybe a matter of personal taste. This can already be seen from a subtle contradiction in Kainaw's reply: As boiling forces out the air, freshly boiled water contains less oxygen, as he rightly states. But then, the oxygenated water of this "O-bar" would be like stale water where air has been allowed to seep back in. One other point: Your tea box's instructions violate coventional tea coinnessuers' wisdom: While black tea should be prepared with freshly boiled and still boiling water, green tea's flavour is said to get "burned" from to hot water. Hence, the standard recommendation is to boil the water (to force out the air), and then wait a little to let it cool down to ca. 80 degrees Celsius before pouring ot over the leaves. However, in my opinion more important for optimal flavour is to (a) not use tea bags but real leaf tea (which need thew full volume of the teapot to unfold and uncrumble) and (b) use "soft" water, i.e. water with low calcium carbonate content. Simon A. 22:45, 6 November 2006 (UTC)

The biggest difference (IMHO) is to use Brita water, which is demineralized, or distilled water. The worst is to use extremely hard water. Also see: Aerated water --Zeizmic 23:03, 6 November 2006 (UTC)

I believe it's recommended that you don't let the water boil violently. When it starts to bubble, that's when the water's ready. Also, taste is really acquired. I notice good coffee but not tea, because I drink coffee a lot more often. Some people can't tell Coke and Pepsi apart either, and I used to be able to, when I only drank Coke. Now I can't as much, except for the slight aftertaste from artificial sugars in Pepsi. --Wirbelwindヴィルヴェルヴィント (talk) 00:50, 7 November 2006 (UTC)
But be sure to pour the water at its hottest, immediately after it's boiled. Pouring water that has been boiled but has been left to cool even a few degrees, gives a sub-optimal tea. Douglas Adams had something to say about this in The Salmon of Doubt. JackofOz 03:38, 7 November 2006 (UTC)
Well actually not true for green tea according to above and the green tea article Nil Einne 11:04, 7 November 2006 (UTC)
Simple experiment: Fill one cup with room temperature water and one with boiled water that have been allowed to cool (maybe put the boiled water in a sealed container to reduce the amount of oxygen it can re-abosrb as it cools). Then compare the taste. --Sherool (talk) 09:53, 7 November 2006 (UTC)
Sorry to have to say this but a rather bad expirement too IMHO. You should at least carry out a blind experiment if not double blind so you'd probably need someone to assist you, maybe two. There are of course numerous ways you could carry out a double blind experiment by yourself but it might be easier just to get people to help. Nil Einne 11:08, 7 November 2006 (UTC)
Well, you'd certainly get the biggest effect with distilled water, but whether that means the best tea or not is a matter of taste. But I think most people's tastes would prefer some mineral content in the water. There is, after all, a reason why we don't use distilled water for making beer and whisky. --BluePlatypus 20:03, 7 November 2006 (UTC)

[edit] scientific discoveries

Could someone name some scientific discoveries from people with NO formal education in the field of the discovery? (Excluding, of couse physicist who discover something about chemistry, and cases like that).132.231.54.1 21:59, 6 November 2006 (UTC)

How old do you want to get? I'd be willing to bet the guy who discovered fire had no formal education. I'm even certain that the guy who invented the wheel had no formal education. --Kainaw (talk) 22:04, 6 November 2006 (UTC)

I don't believe either Ben Franklin or Thomas Edison had much of any scientific training, and they discovered/invented quite a bit. StuRat 22:06, 6 November 2006 (UTC)

You are pretty much correct sir. Add in Michael Faraday and Henry Bessemer.Edison 00:40, 7 November 2006 (UTC)ETA Also add in Zénobe Gramme who built an excellent motor and generator in the 1870's which inspired both Thomas Edison and Nikola Tesla (Tesla of course had a superb university education in electrical physics).Edison 16:21, 7 November 2006 (UTC)

In former times, there was not really a physics education as a subject in its ow right. In medieval time it was just hidden somewhere between medicin and astrology, later there was natural philosophy. Still, there are well-known examples of amateurs: The first clear statement of the first law of thermodynamics, conservation of energy, is often credited to Julius Robert von Mayer, a ship physician, who got the idea from observing horses. The Mpemba effect is a contemporary example, though here it is probably exactly Mpemba's lack of formal education that made him insist on this phenomenon that used to be well known but got fogotten as it seemed (only seemed, of course) to contradict science. I have the feeling that I should know much more examples but I have to think about it. Simon A. 22:55, 6 November 2006 (UTC)

Hows about Gene Sparling? This "entrepreneur" and "amateur naturalist" was an author on a remarkable paper published in Science last year [5]. His (now disputed) discovery? The Ivory-billed Woodpecker (Campephilus principalis), previously thought to be extinct since 1944. Rockpocket 04:59, 7 November 2006 (UTC)
Well, I wanted examples as new as possible. At ancient times it seems to be easier to discover something. In confrontation with modern science seems to be more difficult to come along without formal education132.231.54.1 13:27, 7 November 2006 (UTC)
Oh there's plenty for amateurs to do, just not as much in physics. But there are, for instance, plenty of discoveries being made all the time by amateurs in areas like Astronomy and Biology. --BluePlatypus 19:59, 7 November 2006 (UTC)
Yeah? Tell me a couple of this discoveries in the last years...132.231.54.1 21:26, 7 November 2006 (UTC)
Amateur astronomy is indeed a good point. As professional astronomers observe today with specific goals in mind, certain kinds of discoveries are quite commonly made by star-gazing amateurs. This mainly means comets, as they can be spotted with amateur equipment once they come close but due to their elliptical orbit, many comets come close to the sun and the earth only rarely. Famous examples: Thomas Bopp, codiscoverer of the Comet Hale-Bopp is an amateur, as is Yuji Hyakutake, dicoverer of the Comet Hyakutake. Note that both are great comets. Amateur astronomy#Famous Amateur Astromoners lists more examples. Simon A. 21:41, 7 November 2006 (UTC)
"At ancient times it seems to be easier to discover something." This is just the benefit of hindsight. Anything legitimately "easy" to discover — from a conceptual standpoint, from a technical standpoint, from any standpoint — does not need to be "discovered". History makes discovery look "easy" only because we know who was "right" and who was "wrong," who was able to think outside the box and who was able to utilize a new instrument in a new way. The fact that the moon has mountains on it is a pretty "easy" think to discover once you have a telescope, but it took well over two thousand years of civilization before all of the pieces came together for that to occur, conceptually and technically (to speak nothing of the social circumstances which allow one to think that gazing into the night sky is a good way to make a living!). That being said, the trend in science since the 19th century has been to become increasingly specialized and to use increasingly specialized language, something which generally impedes against those not versed in the specialization or the language to come in from outside and have something to meaningfully contribute. That being said, it is of course not impossible, but it is to be remembered that all great discoveries are the exceptions and not the rule of scientific practice. Most scientists do not make "big" discoveries, now or then. --Fastfission 03:57, 8 November 2006 (UTC)
Antony van Leeuwenhoek, the father of microbiology, was a fabric merchant who started using his microscopes for other puposes than examining fabics. DirkvdM 05:58, 9 November 2006 (UTC)


Anyway, the question is still on the air. Is it still possible to do it nowadays or does it belong to the past? Perhaps modern technology makes it impossible to laymen to discover something...132.231.54.1 12:16, 9 November 2006 (UTC)