Wikipedia:Reference desk/Archives/Science/2011 October 20

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October 20[edit]

Identify this insect[edit]

Can you identify? Let me know on my talk pageHubert Derus 17:32, 9 August 2006 (UTC)[reply]

Can anyone identify this insect? I found it by looking for images with short filenames; this one was uploaded in 2006 and has still not been identified. PleaseStand (talk) 17:02, 19 October 2011 (UTC)[reply]

As a note to those trying to answer this, Hubert didn't say where he took the photo, but other photos he uploaded around that time, taken with the same camera, were taken in east-central Canada, including one in Boyd Conservation Area. -- Finlay McWalterTalk 18:44, 19 October 2011 (UTC)[reply]
I think that's a black blister beetle -- there is a picture of one in our article, and you can find a bunch more with a Google Image search. They are very common. Looie496 (talk) 19:01, 19 October 2011 (UTC)[reply]
The black blister beetle is hairy and multi-colored with antennae that look beaded. This animal is uniformly colored, has a gap between abdomen and thorax (although that may be camera angle) differs in exact shape of the elytra, and doesn't have the obviously beaded antennae. μηδείς (talk) 20:31, 19 October 2011 (UTC)[reply]
This comment was based on the picture at the top of the article which was not the black blister beetle as I had assumed. As noted below the second image in that article is much more similar. μηδείς (talk) 17:32, 20 October 2011 (UTC)[reply]
Thought it was some sort of juvenile elephant weevil myself, but I'm not sure if Canada has any. --Wirbelwindヴィルヴェルヴィント (talk) 21:20, 19 October 2011 (UTC)[reply]
The photo BENEATH the info box on the blister beetle page looks pretty close, it's not multicolored or hairy and the antenna don't look dissimilar if you take blurring into account.. Vespine (talk) 21:37, 19 October 2011 (UTC)[reply]
It is a blister beetle (family Meloidae). And no, black blister beetles, as the name suggests, are uniformly black. Anyway, the quality of the picture for identification is not ideal. The colors are washed out (you can not see the actual color of the legs and head), the posterior tip of the elytra are obscured, the body is viewed from an angle, and the antennae are blurred and probably angled as well, the leg segments are also blurred.
The only thing, however, that you can be sure of given the quality of the picture is that it belongs to the genus Epicauta (which has around 173 species in North America). Even then species are quite hard to tell apart. There is a key to North American species here, but it's rather technical and only available in preview.
Anyway, the following are species of the genus found in East-Central Canada (Ontario, Manitoba, Quebec) which usually appear on August (date the photo was taken), from the most likely species to the least likely, with descriptions. Note that coloration can vary between populations:
  • Epicauta pennsylvanica - the black blister beetle. Has a uniformly black body, but occurs June to July (might be a late emerger).
  • Epicauta murina - the dark blister beetle. Dark gray in color.
  • Epicauta cinerea - the clematis blister beetle. Black in color, usually has lighter colored wing and thorax margins.
  • Epicauta fabricii - The ashgray blister beetle. Light ashy gray with black antennae
Unlikelier identifications:
-- Obsidin Soul 00:40, 20 October 2011 (UTC)[reply]

I thought a bit more about this picture; the insect is only a small part. What kind of plant is probably shown in the picture? PleaseStand (talk) 02:46, 20 October 2011 (UTC)[reply]

That's harder to tell than the beetle actually, it's only the tip of the plant, no flowers or mature leaves. It could be anything from Asteraceae which has dizzying numbers of species. Could be asters, ironweed, horseweed, one of the grass-leaved goldenrods, etc.-- Obsidin Soul 07:49, 20 October 2011 (UTC)[reply]

Shark longevity myth[edit]

Maybe this should be an entertainment question, but I'm not sure. In Jaws, there's a mystifying moment where the police chief has been reading about sharks and says, "You know, people don't even know how old sharks are? That they live two, three thousand years? They don't know!" This passes without any comment, and it's implied that he recently acquired the "fact" from some book. Was this ever a serious and widespread belief? If so, why? I understand that there was once some debate about the longevity of great white sharks, which were alleged to live up to a hundred years, but it's quite a leap to go from a hundred years to three thousand. LANTZYTALK 01:45, 20 October 2011 (UTC)[reply]

Hard telling, but I googled [age of sharks] and this page[1] came up, saying that no one knows how long the Great White's lifespan is. They estimate maybe a hundred. But since they don't know, that guess might as well be a thousand. ←Baseball Bugs What's up, Doc? carrots→ 04:42, 20 October 2011 (UTC)[reply]
According to Wikipedia "they can have a life span of over 30 years" (unreferenced).--Shantavira|feed me 07:19, 20 October 2011 (UTC)[reply]
A thousand seems like a pretty silly guess for a vertebrate. See List of long-living organisms — they don't go much over 200 years, and most of those are slow-metabolism tortoises. There are plants that live on the order of magnitude of thousands of years, and many invertebrates (e.g. corals), but that's it. --Mr.98 (talk) 14:57, 20 October 2011 (UTC)[reply]
It's good to keep in mind that Jaws was fictional, and that line might have been thrown in just for dramatic effect. In fact, the author, Benchley, later expressed remoras remorse for having made sharks look bad. Although your typical great white can pretty well live up to its reputation for ferocity. However, it's unlikely it would channel Moby-Dick and deliberately go after a specific human. ←Baseball Bugs What's up, Doc? carrots→ 22:51, 20 October 2011 (UTC)[reply]
I sea c whut u did thar.-- Obsidin Soul 06:18, 21 October 2011 (UTC)[reply]

How to clean up the Pacific Garbage Patch?[edit]

Would anyone have any ideas on how to clean up one of the worst environmental disasters ever? (At the size of two states of Texas, this makes the BP spill not look as bad as the media made it.

My idea: Repurpose retired oil tankers and net in the garbage?[edit]

Would it be possible to take in retired oil tankers to that region of the Pacific and pull special netting behind the ship to capture the trash, sift out the wildlife, and dump the trash in the cargo holds?

Or possibly, suck in the garbage-infested waters and use a special pump/sifting apparatus to keep the trash and pump out the now-purified water, as well as other objects not intended to be stored in the cargo holds, such as fish and other marine life? I would hope some algorithms would be created for such sifting machines.

If it is possible to make such trash-capturing ships, then what other hurdles would there be to getting this done?

Also, if those above methods can't work, why, and what could work better instead? --70.179.174.63 (talk) 09:47, 20 October 2011 (UTC)[reply]

These ideas seems well within the realms of possibility. But there are at least two factors that are missing from your fine plan. Firstly, international commitment to clear up the mess and secondly, finance for the purchase, recommissioning, maintainance and operation of the vessels. Sort those two out and we are getting nearer to a winning idea. Richard Avery (talk) 14:08, 20 October 2011 (UTC)[reply]
Who will pay for it? Who will do it? I've seem many people pay to go out and take pictures of it, but is anyone concerned enough to go out there and actually pick of some of the trash themselves? Right now, the interest appears to be in complaining about it and trying to get others to do the work. -- kainaw 14:11, 20 October 2011 (UTC)[reply]
Surely you recognize the futility of small individual efforts to clean up something that is twice the size of Texas, much of which is relatively deeply under water. It would be a huge project for even a major state to take care of. Taking photographs of it — with the goal of drawing more attention to it — is probably more helpful in the long run than picking up a few isolated pieces of trash and carrying them home. --Mr.98 (talk) 14:48, 20 October 2011 (UTC)[reply]
Might I just point out that cleaning it up would be nice, but unless the processes that lead to its formation are also addressed, it will just re-form again. --Mr.98 (talk) 14:48, 20 October 2011 (UTC)[reply]
But since plastic can be recycled, you could get some money back from this enterprise. 88.8.75.87 (talk) 14:50, 20 October 2011 (UTC)[reply]
What profitable form of plastic recycling is there? In California, Missouri, and South Carolina (the states I've lived in), the loss of revenue in plastic recycling is offset with taxes to make it appear that there is money in recycling plastic. -- kainaw 14:53, 20 October 2011 (UTC)[reply]
From the article: "...a large, visible debris field is, however, a mischaracterization of the polluted region overall, since it consists primarily of particles that are generally invisible to the naked eye" A net only gets the largest, newest pieces. At an estimated 5 kg per km2, it is not very dense at all which makes cleaning far more difficult. 75.41.110.200 (talk) 15:00, 20 October 2011 (UTC)[reply]
I don't know the specifics in these states, but I wouldn't be surprise if their business idea were to run their business with losses, and therefore get subsidies. That doesn't mean that plastic recycling - or other forms of plastic reutilization - is never profitable. 88.8.75.87 (talk) 15:04, 20 October 2011 (UTC)[reply]
See http://www.sciencenewsforkids.org/2011/10/cleaning-clothes-dirties-oceans/.
Wavelength (talk) 15:46, 20 October 2011 (UTC)[reply]
Why? That seems rather irrelevant to this discussion. --Mr.98 (talk) 17:11, 20 October 2011 (UTC)[reply]
Most of the particles are so small as to be invisible, or nearly so. I can't imagine any "netting" that would pick that stuff up, but not disrupt the wildlife of the region. Or even not get clogged by the wildlife of the region. APL (talk) 21:25, 20 October 2011 (UTC)[reply]
The OP did say either 'sift out the wildlife' or 'pump out the now-purified water, as well as other objects not intended to be stored in the cargo holds, such as fish and other marine life'. Since there's no magic way to sort out wildlife from your unwanted stuff instantly and the very actions of catching or pumping them is going to kill many of them even if there were so magic way, this sounds like a good way to kill more wildlife then you could ever hope to save to me. Nil Einne (talk) 22:28, 20 October 2011 (UTC)[reply]
There is also the assumption that the marine life that is living in the area will be better off without the trash. It is possible that the marine life living there is living there because it is a beneficial place for them to live. -- kainaw 13:09, 21 October 2011 (UTC)[reply]
Pacific Garbage Patch says there may be 100 million tons of garbage. A Capesize cargo ship can typically carry 150,000 tons. So it would be a big operation. And then you have to put the garbage somewhere: I'm having trouble finding reliable statistics, but that seems to be something of the order of the USA's total annual garbage production, or the total size of everything ever dumped at Fresh Kills. --Colapeninsula (talk) 10:09, 21 October 2011 (UTC)[reply]
You could use the garbage to build an island, set up your own micronation tax haven/casino resort, and use that to pay for the expenses of the cleanup. (Please discuss with your financial advisor first. Also, the island may float away.) --Colapeninsula (talk) 10:17, 21 October 2011 (UTC)[reply]
Folks, a little reading comprehension here! The article already mentions Project Kaisei. Though personally I think it's more believable that microorganisms will accidentally or on purpose learn how to degrade the major varieties of polymers. Wnt (talk) 13:31, 21 October 2011 (UTC)[reply]
Eh? That article itself says "Findings suggested that the presence of small debris, of a similar size to the existent marine life, could prove an obstacle to cleanup efforts.[15]" and "The initial feasibility mission aimed to collect 40 tonnes of debris, using special nets designed not to catch fish, in two passes through the field". I don't see any evidence that even those involved in the project believe there is some magically way to sort out marine life from the junk or are suggestting the feasibility of either of the OPs suggestions if you don't want to risk considerable harm to the marine life. Nor does the article seem to raise any points to many of the other concerns like the futility of trying to clean something up if you haven't done anything to stop it reoccuring or the shear amount of stuff there (the test project apparently aimed to collect 40 tonnes or 0.00004% of what's there if the figures someone provided above are accurate). Nor is there anything in the article suggesting collecting the stuff would be a profitable exercise. Nil Einne (talk) 11:05, 22 October 2011 (UTC)[reply]

oxygen masks drop on planes[edit]

Do they (I mean the masks, not the planes) drop when there's fire on board? AFAIK, they drop when the cabin pressurization system fails, which is not necessarily the case during a fire. So, may it be that the plane gets filled with smoke and you cannot use your oxygen mask? 88.8.75.87 (talk) 14:46, 20 October 2011 (UTC)[reply]

According to Emergency oxygen system they don't drop so that they don't supply extra oxygen to the fire. 75.41.110.200 (talk) 15:33, 20 October 2011 (UTC)[reply]
And what happens if you have a pressure drop and fire on board? Is there a mechanism to block them? 88.8.75.87 (talk) 20:14, 20 October 2011 (UTC)[reply]
Fires need oxygen too. If the oxygen pressure falls below what is safe for humans that will actually put out many fires and discourage the spread of the ones it doesn't extinguish. Dragons flight (talk) 20:34, 20 October 2011 (UTC)[reply]
As an aside: A low oxygen atmosphere is used to suppress fire in archives etc. --Aspro (talk) 20:48, 20 October 2011 (UTC) [reply]

Manufacturing Technique of First Transistor Makers[edit]

How did Bardeen and Brattain (or, more likely, their technicians) manufacture/create and dope the purified silicon used in the first transistor, as viewable here? Obviously, they didn't have the nice multimillion-dollar electronic-grade-silicon producing and chip making machines (with transistors in them themselves) now available at Intel factories. From the article on Jan Czochralski, "Americans Gordon K. Teal and J.B. Little from Bell Labs used this method to grow single germanium crystals, which began its use in producing suitable semiconductors." So they didn't use the Czochralski process to get their material into a monocrystalline form(which don't suppose it was, and that's not even questioning how they made their purified silicon in the first place in 1947, or (sufficiently well) doped it). 20.137.18.53 (talk) 15:55, 20 October 2011 (UTC)[reply]

The first point-contact transistor used germanium, not silicon. Germanium crystals were grown using processes developed by Karl Lark-Horovitz at Purdue in the years just before and during World War II. This site describes the process of growing and doping germanium that they used at Bell Labs — sounds pretty much like the Czochralski process to me, but I'm no material scientist. The first silicon transistor was not made until some time later (1954). It has its own nice story, though I don't know what TI was doing to get their silicon (but since the same guy—Gordon Teal—was involved as was involved in growing germanium, he is probably the guy to look into). If you are really curious about the technical aspects, I might recommend Lillian Hoddeson's Crystal Fire: The Birth of the Information Age (1998) which is the authoritative history of the transistor and full of technical info. --Mr.98 (talk) 16:52, 20 October 2011 (UTC)[reply]
Thanks!20.137.18.53 (talk) 17:12, 20 October 2011 (UTC)[reply]

How Long?[edit]

Beam-powered boat propulsion on the Cam

If I were to travel 211,630,513,434,609.9 using beamed propulsion, how long would it take for me to get there? By the way I wasn't sure if this was in the right category. — Preceding unsigned comment added by Lightylight (talkcontribs) 20:51, 20 October 2011 (UTC)[reply]

Its OK. I don't think we have a category for this kind of question anyway. --Aspro (talk) 20:55, 20 October 2011 (UTC)[reply]
What exactly is "beamed propulsion"? -- Obsidin Soul 20:57, 20 October 2011 (UTC)[reply]
Wikipedia has an article on everything. Beam-powered propulsion --Aspro (talk) 20:59, 20 October 2011 (UTC)[reply]
Needless to say, it depends on the speed, distance units, local gravity constants and things...--Aspro (talk) 21:04, 20 October 2011 (UTC)[reply]
Dunno. OP could mean something scifi like a spaceship that is actually propelled by photons, or something medieval like a rowboat. :P-- Obsidin Soul 21:07, 20 October 2011 (UTC)[reply]
Quoting a 1014 value, I don't think its to do with a medieval row boats (although I have been known to be wrong once or twice).--Aspro (talk) 21:18, 20 October 2011 (UTC) [reply]
Beam-powered boat propulsion is called punting. μηδείς (talk) 21:30, 20 October 2011 (UTC)[reply]
OK, so I have been (possibly) been proven wrong thrice, but the value provided is decimal (ends in .9) and punt poles are measured in duodecimal units. And why has he got that black sail raped around his shoulders?--Aspro (talk) 21:40, 20 October 2011 (UTC)[reply]
"raped" around his shoulders? Maybe you meant "draped".  :) -- Jack of Oz [your turn] 20:35, 21 October 2011 (UTC) [reply]
Given the rather extreme precision of the question, a little Googling and logic suggests the the distance is probably in miles - it is almost exactly 36 light-years. This is still no help in answering the question, beyond the obvious 'more than 36 years' - realistically, a heck of a lot more. I can't imagine there is any conceivable beam-powered propulsion system that would operate over such distances, so it really comes down to how much initial acceleration your spacecraft gets, before it has to coast. Of course, beam-power isn't going to slow you down you at the other end of the journey - unless there is another beam already set up at the other end... AndyTheGrump (talk) 21:49, 20 October 2011 (UTC)[reply]
So really the OP is asking for an estimate for the velocity achievable by beam propulsion. Why didn’t s/he say so in the first place? Now where did I put my slide-rule...?--Aspro (talk) 21:59, 20 October 2011 (UTC)[reply]
And another quick search of 36 light years away gives this result, lol... That reminds me of the joke about the guard at the museum who says the dinosaur fossil was seventy million and three years old. When asked in astonishment about the precision of the date, his reply is that when he started three years ago, he was told it was 70 million years old. Vespine (talk) 23:53, 20 October 2011 (UTC)[reply]
roflz -- Obsidin Soul 06:14, 21 October 2011 (UTC)[reply]

re: the man with the golden gun's golden gun[edit]

Assuming expense is not a problem, is gold is gold really a suitable material for making a gun (as in pistol rather than artillery piece) out of? Or is it too soft, or too brittle or whatever? — Preceding unsigned comment added by 86.159.8.228 (talk) 21:05, 20 October 2011 (UTC)[reply]

One can make hard alloys of gold but I think you'll find all golden guns are just gold plated -22 caret- versions of standard fire arms.--Aspro (talk) 21:11, 20 October 2011 (UTC)[reply]
Yeah, pure gold is much too soft and melts at a relatively low temperature which would be less of a problem. Dualus (talk) 21:13, 20 October 2011 (UTC)[reply]
Just occurred to me. Can you imagine just how heavy a solid gold gun would be. It would absorb the recoil well though... Must order one tomorrow.--Aspro (talk) 21:24, 20 October 2011 (UTC)[reply]
You might be interested in this gold plated sub-machine gun. It's a British Sterling L2A1, apparently in demand from Middle-Eastern folk with more cash than good taste. You can see one captured in Iraq in this video at 1:35 although the American "expert" calls it a Beretta. Alansplodge (talk) 23:21, 20 October 2011 (UTC)[reply]
Gold is about 2.5 times as dense as steel. Francisco Scaramanga says the gold plated gun of the novel was a Colt Single Action Army; had that been solid gold its weight would have gone from about 1000g to about 2500g. The gun in the film is a rather teensy prop (so we can't get a weight for it) but it's if anything smaller than Bond's Walther PP. The PP weights around 600g in steel, so it'd be about 1500g in gold - a fair amount less than a IMI Desert Eagle. I don't see a weight for the Beretta 418 that Bond formerly carried (a "ladies gun"), but it's surely less than the 280g of the similar-but-more-substantial Beretta 950 Jetfire. So tl;dr: heavy, but not unmanageably so. I fear, however, that a gold gun would absorb the recoil by deforming itself into a hopelessly unworkable shape, such that had Scaramanga missed with the first shot, the second would surely have blown his own face off. -- Finlay McWalterTalk 23:11, 20 October 2011 (UTC)[reply]
I've just been into the kitchen and strapped 5½ pounds to my wrist. If you think you can out fire an opponent with that weight in your hand, then... well ! However, the gold filings received from the exploding chamber would save one a huge dental bill. --Aspro (talk) 23:36, 20 October 2011 (UTC)[reply]
A Smith & Wesson Model 500 weighs 5.1 pounds; its article shows a woman firing one. This video shows some rather burly blokes firing one (but unfortunately there's no soundtrack). It's going to spoil the lie of your Saville Row suit, but it's not impossible to use. The Pfeifer Zeliska .600 Nitro Express revolver, however, really is daft (it rather stretches the definition of "handgun" when you need a table). -- Finlay McWalterTalk 23:56, 20 October 2011 (UTC)[reply]
You're right. Not impossible to use. I was thinking along the lines that a short nose .38 is easier to point at a moving target (which is why many law enforcement officers use them) against a bozo welding a Magnum -who is refusing to stand ruddy still. Mind you, having a Pfeifer Zeliska .600 Nitro Express revolver in your whistle and flute] would probably give Mae West an instant orgasm ( apologies to lady readers – a mans' joke).--Aspro (talk) 21:55, 21 October 2011 (UTC)[reply]


Silver-plated gold-core bullets from a Colt SAA? Who is he expected to fight - cowboy werewolves? -- Finlay McWalterTalk 23:19, 20 October 2011 (UTC)[reply]

Faster than light neutrinos?[edit]

I was imagining a simplification to this latest discovery at CERN. How about that the light appears faster due to a compression shock wave. They say neutrinos are everywhere so perhaps the experiment focused the beam of neutrinos and pushed the neutrions ahead of the beam in a shock wave.

I imagine it a bit like a vortex cannon (a big simplification of course) but when the air hits the target I bet the air that hits the target first is a shock wave of air and not the original air particles.

Now neutrinos are not air of course but perhaps they behave crudely in this manner and hence cause the early 60ns appearence of light. — Preceding unsigned comment added by 92.30.216.128 (talk) 22:08, 20 October 2011 (UTC)[reply]

Einstein predicts not only that matter cannot reach (or exceed) c, it also implies the same for information. If you allow any kind of faster-than-light communication, you can concoct a path for information to go back into the past. So the shockwave idea would not resolve that problem. There are many other possible explanations for the result - the most plausible seems to be that GPS used for timing and distance measurements has some unexpected hitches. See [2]. --Stephan Schulz (talk) 22:38, 20 October 2011 (UTC)[reply]
Time can go backward ' thanks Water Nosfim — Preceding unsigned comment added by 212.199.175.104 (talk) 10:05, 21 October 2011 (UTC)[reply]
Sometimes I wish it would for a while!Dbfirs 13:38, 21 October 2011 (UTC)[reply]
To put it another way, your shockwave theory would mean the speed of sound in neutrinos is faster than the speed of light, which would require individual neutrinos to briefly travel faster than light to transmit the shock. --Carnildo (talk) 00:01, 22 October 2011 (UTC)[reply]