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February 4

drawing planets orbits around earth

I wish to produce the like of this image. I want it to make it myself so I can release it as creative commons. Preferably, I would like to include the orbits of Venus and Mercury as well. Is there a tool for this job? אילן שמעוני (talk) 01:11, 4 February 2021 (UTC)[reply]

The tool XEphem is capable of calculating and charting ephemerides, but I don't know if it will directly display this kind of chart. The calculation part has been isolated and made available in the form of the Python library pyephem. I have not examined its precise functionality, but our article Ecliptic coordinate system gives formulas for converting between equatorial and ecliptic coordinates, if necessary. List of information graphics software lists many apps that can convert a data set to a chart. --Lambiam 10:06, 4 February 2021 (UTC)[reply]

Vertical bar in chemical formula

The chemical formula given for lazurite is (Na,Ca)₈[(S,Cl,SO₄,OH)₂|(Al₆Si₆O₂₄)]. What does the vertical bar represent? –LaundryPizza03 (d c̄) 14:22, 4 February 2021 (UTC)[reply]

This discussion forum has some ideas. --Jayron 32 15:33, 4 February 2021 (UTC)[reply]

Almost every source presents a different formula. I saw this specific version in the 1992 book A Guide in Color to Precious & Semiprecious Stones.^[1] A 2000 research article in American Mineralogist has (Na,Ca)₈[Al₆Si₆O₂₄](SO₄,S)₂.^[2] --Lambiam 16:51, 4 February 2021 (UTC)[reply]

Cloning using CRISPR/gene editing question

Do you believe that it would ever become possible for us to edit the genes from any cell from our bodies (for instance, a skin cell)--saying, using CRISPR or whatever--and transform this cell into a zygote/embryo? Not into a sperm or egg, but rather into a zygote/embryo. Futurist110 (talk) 22:05, 4 February 2021 (UTC)[reply]

Yes. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:13, 4 February 2021 (UTC)[reply]

Would that also apply in regards to successfully transforming non-human bodily cells (for instance, a cat's or dog's skin cells) into human zygotes/embryos using gene editing? Futurist110 (talk) 01:38, 5 February 2021 (UTC)[reply]

Maybe. ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:57, 5 February 2021 (UTC)[reply]

If I peel and mush some bananas, hollow out an orange and stuff it with the banana mush, have I successfully transformed the orange into a banana? --Lambiam 10:15, 5 February 2021 (UTC)[reply]

No, but it's a poor analogy, because the banana mush doesn't actively manufacture more banana structure and banana metabolism proteins, whereas human genes inserted into a non-human cell do generate human-cell proteins and might indeed, if done right, cause the cell to transform into a human zygote.

That said, while I concur with Bugs' "maybe", Futurist110's proposal of using non-human cells apparently adds pointless difficulty to the exercise: why, in the real (future) world would one use non-human cells when human cells would surely be available? Well, Futurist110 is (I understand) kicking around ideas for a science fiction novel, so there might be plot or background details that necessitate it, such as the exploitation of a loophole in laws forbidding human zygote gene editing. {The poster formerly known as 87.81.230.195} 90.200.40.9 (talk) 23:19, 5 February 2021 (UTC)[reply]

Calculating the distance range of commercial over-the-air FM radio stations

Now, I know the internet is full of forum questions of similar types, where people are being answered there would be too many undefined variables in their question than to really give an answer. However, I'm trying to find a simple online calculator (or maybe a formula, but I'm afraid it won't be easy to calculate on paper) for the following given specific conditions:

Let's assume we have a fully flat area for hundreds and hundreds of square miles, like a desert or prairie, without any forests, hills, or mountain obstacles.
We have a number of FM radio towers. Each being a simple, omnidirectional isotropic radiator, which sets antenna gain at 0dB on the transmitter side. They all broadcast at or around a frequency of 100 MHz. The towers only differ in height and watt power.
We know the exact individual height of every tower above sea level (in metric MASL), ranging between c. 60 to c. 250 meters.
We know the individual watt power of every tower, ranging from 0.01 kW to 20 kW.
The receivers are simple car or home kitchen radios with small whip antennas (which probably gives them an antenna gain of c. 2 to 3 dB), all at c. 1 to 2 meters above ground.
We define the limit of transmission range as the area within which the signal quality or strength for the receivers does not drop off below 50dBuV per meter.

So, what I'd like to calculate would be the individual distance range of every single tower, based on those factors and atmospheric path loss, while ignoring specific weather conditions. And no, I'm not asking about radio aka radar horizon, as that limit is most likely far above the capacities of those towers, anyway. --46.93.157.63 (talk) 23:48, 4 February 2021 (UTC)[reply]

Since you already give a strength limit of 50dBuV per meter a lot of your other assumptions are not required. So your volts per meter, can convert to watts per square meter (V/m)²/377, which for you is 2.65×10⁻¹⁰. You can then work out the size of the sphere 4πR² so your power flux: P/(4πR²) > 2.65×10⁻¹⁰. Substitute your transmitter power in P and solve for R. For 10000 watts I get 1730 km. This may sound big, but don't forget that the Earth is curved and there are hills and trees that absorb. So reality will be less. Due to reflection from the ground, the signal can also be doubled in some places, (and zeroed in others). Also consider that the transmitter will not be isotropic, and will avoid transmitting power down into the ground, and up into the sky. Graeme Bartlett (talk) 00:57, 5 February 2021 (UTC)[reply]

This does not take the path loss into account that is due to signal attenuation in the atmosphere. I further notice that Friis' transmission formula involves the wavelength, so presumably this should be of some significance. --Lambiam 10:09, 5 February 2021 (UTC)[reply]

Yeah, I was about to say that quite a lot of sources and websites make a huge deal out of path loss, Friis formula, wattage, and antenna gain (both on the transmitter and the receiver side), and there are even some websites with tables that claim you can calculate range from kW and HAAT, such as [3] ("How far will my signal go?", source: professional electronics dealer Broadcast Warehouse), and [4]. (Granted, with the first website, the power wattage examples are much smaller, and with the second, the figures are for highly directed transmitters.) (Although some sources claim you have to convert kW into effective radiated power first, not the actual power used or emitted, and that the results from kW (or ERP) and HAAT would be officially grouped into so-called "station classes" designated by the FCC, such as A, B, C, etc., where each FCC "station class" would equal a broadcast range class.)

To the contrary, quite a lot of *OTHER* sources even pretty much claim in response to "How many miles per watt?" questions that power wattage would have no impact at all once you have a tower, and then you could simply take the height of the tower in feet, and 75% of that or so would be the range in miles, acting as if 1 Watt would carry all the way to the radio horizon unchanged once you're 20 feet high. That's rather confusing, as you seem to have radicals on both sides: There seems to be a camp that says HAAT would be everything, and then there's a camp that says it would be entirely up to path loss, Friis formula, wattage, and antenna gain. And all over the internet, both camps seem to be entirely ignoring the other camp's existence, actively denying that the factors given by the other camp have much of any effect at all upon range, or they say those other factors would be far too diverse in real life that you can't really calculate them.

Anyways, from loooooooots of googling and reading, I've found two different solutions to my problem:

a.) Nautel’s Radio Coverage Tool: [5] It's free (though requiring registration). All you have to do is pick your location conveniently from a global map, then enter frequency in MHz, power wattage in kW, HAAT, and pick your type of receiver, and there you go. The thing has access to massive databases of global terrain data to calculate and draw your actual range as a circle around your tower on a map for you at the click of a button. You can also additionally download Google Earth to make the results look really neat, make even more realistic range calculations, and do lots of other stuff.
b.) I've found that there are official, publicly accessible FCC databases for pretty much every single commercial FM station in the USA that also list ranges in miles for every single station. Wikipedia even has a short list like that on its own at List of North American broadcast station classes#Station class description (where Wikipedia even claims that you can calculate ERP from HAAT and kW somehow, though without giving a formula). Unfortunately, no such official lists seem to be available for Germany, which is the actual area I'm trying to find this out for, and when you google for terms such as "FM radio technical broadcast range" in German, all you'll get is results not in miles, but in number of potential listeners, as if listeners would be the official physical electronic measure unit of "technical range". However, I've now come upon an amateur website where thousands of radio enthusiasts have reported FM bandscans from all over Germany to, and the site has used that data to draw rather detailed, confusing maps with ranges depicted as circles, either for every commercial or public broadcaster or for every radio tower used by that station, and are listing the rough broad range radius of every single station or tower derived from all that amateur data also in rough numerical values of kilometers. --46.93.157.63 (talk) 14:07, 5 February 2021 (UTC)[reply]

February 5

Substance in cardoon stalk

I boiled an cardoon stalk. The boiling water, after the addition of vegetable bouillon cube (therefore substantially salt, glutamate and flavorings), was kept in the pot for a few hours, and from clear as it was (slightly yellowish, color substantially due to the addition of the bouillon cube) has turned green! I would have expected to find at the limit a brown liquid, almost black, having had all the time to oxidize, but that color just I would never have expected. To which I think: "... is it pH sensitive?" (the cooking water is particularly calcareous, so the broth should be slightly basic). I add a splash of lemon juice and the broth turns yellow. And adding baking soda turns green again. And here is the question: which substance (or chromophore group) could be responsible for the color change? --87.0.134.53 (talk) 10:26, 5 February 2021 (UTC)[reply]

It's most probably one or more anthocyanin responding to the pH change. Roger (Dodger67) (talk) 14:18, 5 February 2021 (UTC)[reply]

Per Roger, some pigment or combination of pigments is responsible. Anthocyanins are generally blue/red indicators (antho=red, cyan=blue), while something like Curcumin is a yellow/red indicator (the main coloration of turmeric). I am not familiar with a "yellow/green" indicator natural to plants, but clearly they exist. Not sure what specific chemical these are in this case, but such types of compounds are common enough. --Jayron 32 14:25, 5 February 2021 (UTC)[reply]

Carbon emission of rail vs air

If you look at the greenhouse gas emissions of the whole system over a period of time (for example 50 years), are electric trains still much better then air travel? Has this been modelled? 2A02:C7F:C42F:6400:E1C2:D924:23F8:470E (talk) 17:18, 5 February 2021 (UTC)[reply]

Cecil Adams provides a nice overview to this question here.

I believe the paper he mentions at the start of the article is this one. I think that paper, and its citations could provide a very detailed answer to your question. ApLundell (talk) 19:14, 5 February 2021 (UTC)[reply]

Wikipedia has an article on Environmental impact of transport.--Shantavira|^{feed me} 10:28, 6 February 2021 (UTC)[reply]

"A journey from London to Madrid would emit 43kg (95lb) of CO2 per passenger by train, but 118kg by plane (or 265kg if the non-CO2 emissions are included)... The increased warming effect other, non-CO2, emissions, such as nitrogen oxides, have when they are released at high altitudes can also make a significant difference to emissions calculations". BBC: Climate change: Should you fly, drive or take the train?. Note that in Western Europe, most main rail lines are electrified, a majority of which comes from low-carbon generation. Alansplodge (talk) 12:30, 6 February 2021 (UTC)[reply]

Whilst I certainly don't disagree rail travel is better than air travel, I wonder if the emissions comparisons are complete. There's probably a reason these comparisons are always between two well connected capital cities. For instance, generally rail travel from anywhere in the UK outside the Southeast/London area to anywhere on the continent outside the Paris/Brussels corridor will be a two day affair, requiring a hotel stay either in London to catch an early Eurostar, or somewhere along the way on the continent. I doubt the comparisons take into account the extra emissions from the hotel stay etc. Like I said, I very much doubt that would make a difference in the long run, but I do wonder. That is an issue in wider adoption of international train travel from the UK though, for instance, it would take twice as long and cost three times as much for me to make my most regular UK-Europe journey, that's just not feasible in many circumstances. Fgf10 (talk) 14:57, 6 February 2021 (UTC)[reply]

That seems to ignore the possibility of sleeping on overnight trains. Are sleeper cars not a thing any more? It's been a while since I've done it. 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 18:19, 6 February 2021 (UTC)[reply]

Not many of those left, although there is a movement for their renaissance. Fgf10 (talk) 19:40, 6 February 2021 (UTC)[reply]

According to this, "Starting at London St Pancras, your journey will involve at least two changes (one in Paris, one in Barcelona) and a minimum journey time of 13 hours" and the cheapest price is £116. Ryanair can do the same journey in 2 hours 20 mins for £36, but you have to get to and from the airport. Alansplodge (talk)

For what it's worth, most of the UK's rail network outside London and the south-east, apart from the main lines, has not been electrified - it's still running on diesel. I wouldn't be surprised if this was also true in other European countries. Rhythdybiau (talk) 20:41, 7 February 2021 (UTC)[reply]

According to Railway electrification in Great Britain it's 38% but includes all the main routes between major cities. Alansplodge (talk) 01:25, 8 February 2021 (UTC)[reply]

February 6

Why would black holes emit Hawking radiation?

Even light can't escape black holes, then how it can emit Hawking Radiation? Rizosome (talk) 01:42, 6 February 2021 (UTC)[reply]

The second and third paragraphs of the overview section of the article you linked explain it. Matt Deres (talk) 04:10, 6 February 2021 (UTC)[reply]

Melatonin research journal

Does the journal "Melatonin Research" (example article) look any good? Not necessarily for Wikipedia RS purposes but as a research outlet? Thanks. 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 18:17, 6 February 2021 (UTC)[reply]

It seems to be a new journal. The website design is... basic, but a quick scan of the author guidelines looks reasonable. Having say that, it's not in Medline, or has an impact factor yet. Also, most of the papers seem to be from developing countries. That in itself is not an issue, but when you see that exclusively it becomes a warning sign. (Note: this is not to say there is anything wrong with science from developing countries, but it is a hallmark of many a dodgy journal.) Many of the authors do not have institutional corresponding addresses. Another warming sign. A quick scan of randomly selected papers shows acceptance is universally within 3-6 weeks of submitting, suggesting the peer review is likely to be perfunctory (you'd expect some papers to have been sent back for extra work and several months between submission and acceptance). I can't judge the science, it's not my field. But at best I'd classify it as a new start-up journal which has yet to prove itself. Nothing I would sent any serious work in to. Fgf10 (talk) 19:55, 6 February 2021 (UTC)[reply]

Thanks, yeah, I had similar doubts, though I didn't spot nearly as much as you did. What do you think of the entire concept of a melatonin journal? Is that something like a Vitamin C journal? 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 20:39, 6 February 2021 (UTC)[reply]

Kiwifruit with hollow or missing core

I have been eating kiwifruits more or less regularly the last 30 years, but cannot recall ever having seen a kiwifruit with a hollow – or missing – core. But in the box of kiwifruits I bought the other day I have so far seen two such fruits. See image. Is this normal? Are these fruits edible? --Andreas Rejbrand (talk) 19:42, 6 February 2021 (UTC)[reply]

Did you ask your grocer? And remember this motto: "If in doubt / Throw it out." ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:52, 6 February 2021 (UTC)[reply]

One of the pics on the article you linked is also hollow. Perhaps it's a varietal thing? The rest of the fruit seems pretty normal to me; I'd just eat it (assuming it tastes/smells normal and is not otherwise moldy/mushy, etc.) Matt Deres (talk) 03:15, 7 February 2021 (UTC)[reply]

Google finds a few other examples like this Reddit post. One suggested cause was "Suboptimal growth conditions probably, maybe it was too arid". Alansplodge (talk) 14:08, 7 February 2021 (UTC)[reply]

February 7

Do Earth observatories better than space telescopes?

Do Earth observatories better than space telescopes? Even first Black hole image was produced by using observatory. Rizosome (talk) 02:17, 7 February 2021 (UTC)[reply]

Define "better". ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:19, 7 February 2021 (UTC)[reply]

Also, the image was produced by a global set of radio telescopes, as this NG article explains:[6] ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:58, 7 February 2021 (UTC)[reply]

This is largely explained at space telescope. You can often find the answers to your questions more quickly by doing even a tiny bit of searching. Matt Deres (talk) 03:09, 7 February 2021 (UTC)[reply]

Matt Deres I am comparing two things. Rizosome (talk) 06:22, 7 February 2021 (UTC)[reply]

If Earth observatories were indeed "better" than space telescopes, why do you think would anyone spend millions of dollars on developing them? Earth observatories and space telescopes are used for different purposes, so you do indeed need to specify what you mean by "better" if you want a meaningful answer, but it would be easier to actually study the articles, and then come back with a more specific question.--Shantavira|^{feed me} 09:29, 7 February 2021 (UTC)[reply]

What is the diagonal line in this satellite image?

In this satellite image, there is a long straight diagonal line in the upper left corner cutting across a headland of the westernmost island and with a slight but abrupt and arbitrary change of shade all across it. What does it represent? Is it natural? StellarHalo (talk) 06:04, 7 February 2021 (UTC)[reply]

Even at high resolution, I can't see what you describe.--Shantavira|^{feed me} 09:32, 7 February 2021 (UTC)[reply]

I can see a line heading away from the island on a bearing of about 7 or 8 degrees (i.e. slightly to the east of north), if that's the one? It's rather faint, so much so that I wonder why it is of concern? I suspect it's natural, but how to tell? PaleCloudedWhite (talk) 09:46, 7 February 2021 (UTC)[reply]

So that island is Ushant, yes? I can also see a lighter line, which crosses the island, at about 15 degrees from due North. I suspect it's an artefact of the image construction. Either that or maybe a secret underground tunnel between France and Plymouth. Martinevans123 (talk) 10:00, 7 February 2021 (UTC)[reply]

You're right about the heading - I misread my protractor. I suspect that the tunnel theory is going off at a bit of a tangent though (pun intended), even by my standards of protractor competence.... PaleCloudedWhite (talk) 10:13, 7 February 2021 (UTC)[reply]

You can thank my trusty perspex school protractor.... What, no tunnel?? I'll have you know I "put the ys in Wikypedya". Martinevans123 (talk) 10:32, 7 February 2021 (UTC)[reply]

The line is there, but I think it's an artefact. Sentinel-2 tells us the satellite is in a sun-synchronous orbit with a descending node at 10:30 local mean solar time. That means that the satellite made a pass to the SSW in the morning or to the NNW in the evening. Shadows clearly indicate this picture was taken during the morning pass (it would be after sunset in the evening). So the line appears to be parallel to the satellite's ground track. Maybe some effect in the detector? Or, Sentinel-2 scans a strip 290 km wide and the image, when measured perpendicular to the line, is about 180 km. Maybe the northwestern most part was filled in from a different observation? Sentinel-2 (consisting of 2 satellites) makes 1 or 2 scans of this area every 5 days. PiusImpavidus (talk) 10:37, 7 February 2021 (UTC)[reply]

I see a long line, going from the left to the top edge of the image and cutting through the eastern headland of Ushant at a bearing of 21°, and another one, much harder to detect, passing between the two ships close to the upper left corner at a bearing of 16.6° (assuming "up" is true North). Can these be an artifact of image stitching? I cannot think of a plausible natural origin. --Lambiam 10:42, 7 February 2021 (UTC)[reply]

Oh dear, my trusty school protractor has just delaminated. Martinevans123 (talk) 10:53, 7 February 2021 (UTC) [reply]

I see several, parallel, at regular intervals across the watery parts of the whole image: along the north coast, from Ushant, Neïz Vran, Brignogan-Plages, Trégondern, Ploumanac'h; and the south coast from Brignéoc'h, Guilvinec, Merrien. I agree with Lambiam: most likely they are image construction artefacts. Bazza (talk) 11:39, 7 February 2021 (UTC)[reply]

My guess is that we would be talking about an underwater pipeline. Passing watercraft seem oblivious of it. Then again, they might be aircraft. They have beautiful "plumages" stretching to the right. Each craft seems to give off its own color. Bus stop (talk) 01:55, 8 February 2021 (UTC)[reply]

One of the diagonal lines slices through the contrail of one of the aircraft, so that the "blue" and "green" copies of the contrail don't match up on the left and right sides of the diagonal line. The blue and green contrails have also changed their order (green on top to the left of the line; blue on top to the right of the line). This suggests that from one side of the line to the other, we have changed direction -- either the direction of scanning or of the satellite's motion during different passes. --Amble (talk) 22:54, 8 February 2021 (UTC)[reply]

Here's a web page explaining the arrangement of detectors on the Sentinel-2 MSI focal planes: [7]. They are in a staggered pattern where each covers only part of the field of view. The order of the bands reverses from one to the next. There's a small overlap region in the middle. This appears consistent with the stitching you're seeing. --Amble (talk) 23:02, 8 February 2021 (UTC)[reply]

Yes, I concur with your observations. There is a possibility that it is an illusion, but just as you say, the "blue" and "green" copies of the contrail don't match up on the left and right sides of the diagonal line. The blue and green contrails have also changed their order (green on top to the left of the line; blue on top to the right of the line). Not having any expertise in this I am reluctant to state with any degree of assuredness what is going on, but it appears as an error in "stitching" together sections. Bus stop (talk) 06:00, 9 February 2021 (UTC)[reply]

There are three images of the aircraft: in red, green and blue, in order of decreasing wavelength. The multiple imaging may be caused by the focuses being optimized for coincidence at sea level, so that objects at different altitudes have non-coinciding foci for the three wavelengths and have accordingly displaced images. Reversing the order of the bands may also cause the reversal of the order of these displacements. --Lambiam 13:06, 10 February 2021 (UTC)[reply]

Americium in smoke detectors

How much Americium is in a smoke detector? Is it all Americium? UB Blacephalon (talk) 22:41, 7 February 2021 (UTC)[reply]

The general subject is discussed in Americium. — Preceding unsigned comment added by Baseball Bugs (talk • contribs) 23:18, 7 February 2021 (UTC)[reply]

So is it all americium? I've heard people say that not all of the button is americium. Is this true? UB Blacephalon (talk) 23:29, 7 February 2021 (UTC)[reply]

The article says a typical smoke detector uses 0.3 micrograms of Americium. That means that if you somehow extracted the pure Americium from 10,000 smoke detectors, your pile of Americium would weigh about the same as an ant. ApLundell (talk) 23:54, 7 February 2021 (UTC)[reply]

How dangerous would it be? Is pure americium? UB Blacephalon (talk) 01:33, 8 February 2021 (UTC)[reply]

Read the article, for a sense of the danger level. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:09, 8 February 2021 (UTC)[reply]

It doesn't say anything about purity. Is it pure? UB Blacephalon (talk) 04:32, 8 February 2021 (UTC)[reply]

This is explained in the article.

"The process for making the americium used in the buttons on ionization-type smoke detectors begins with americium dioxide. The AmO2 is thoroughly mixed with gold"

ApLundell (talk) 05:17, 8 February 2021 (UTC)[reply]

So its not 100% Americium but AuAmO2? Damn.... 00:43, 9 February 2021 (UTC)

No, mixing it with gold does not make it a compound with gold. Nor does it necessarily impact the danger. Unless it is being surrounded by something that absorbs ionizing radiation (which wouldn't make much sense, since its purpose is to use said ionizing radiation), then it doesn't matter what it is mixed with or surrounded by. What matters is how many moles of the element are their, what isotope of the element it is, and its distance from the living organism that would be impacted by it. The amount of it in a smoke detector is not dangerous. --OuroborosCobra (talk) 18:06, 9 February 2021 (UTC)[reply]

Oh so is the majority americium? Is there a way to purify it? UB Blacephalon (talk) 01:30, 10 February 2021 (UTC)[reply]

Again, it's purity is entirely irrelevant. Radioactive decay is not governed by sample purity. The decay rate is a first-order process, a half-life. If you have 0.3 micrograms of Americium-241 in your smoke detector today, then in 432 years, you will have 0.15 micrograms of Americium-241 in your smoke detector. Whether it is surrounded by gold or plastic or glass, whether it is incredibly low in purity within whatever matrix contains it, all is entirely irrelevant. All that matters is how much Americium-241 is in the smoke detector. --OuroborosCobra (talk) 01:59, 10 February 2021 (UTC)[reply]

Well, hmm, I don't think that's exactly true. Americium-241 is an alpha emitter, and alphas have very poor penetrating power. If your americium were dispersed through a thick matrix, most of it would be wasted, because the alphas would be absorbed before they ever got to the detection chamber. It doesn't matter how "pure" it is per se, but it does matter how much stuff is between it and where the alphas need to go. I would speculate that it's deposited thinly on a foil surface or something. --Trovatore (talk) 06:32, 10 February 2021 (UTC)[reply]

addressed that in an earlier comment I made in this discussion, but Blacephalon doesn't seem to be as interested in the ability of a smoke detector to function at all as much as he is "will it kill me" and "how pure is it," as well as a question that I really don't know how to answer of "is all the americium made of americium." I mean, all of the oxygen atoms in water molecules are, in fact, oxygen atoms, just as all of the americium in a smoke detector is, in fact, americium. That's true regardless of the purity of the radio source material. All of the americium in it is americium, whether is constitutes 100% or 1% of the matrix. The surrounding matrix certainly might impact how well the smoke detector works, but not whether the americium atoms are americium atoms, and not their decay rate. --OuroborosCobra (talk) 21:22, 10 February 2021 (UTC)[reply]

So its just americium, that's the point? Huh, oh well a bit of Americium is enough I suppose. The most I can do is just keep collecting samples. Its not like its THAT dangerous, right? UB Blacephalon (talk) 06:12, 10 February 2021 (UTC)[reply]

I do not know what you mean when you say "it's just americium." Americium atoms are americium atoms, yes, no matter what you surround them with, no matter if they are in a compound or not. The oxygen atoms in water are all oxygen atoms, that isn't impacted by the presence of hydrogen. The chairs in my office are all chairs, even if there are also some couches and computers in the same room. The purity of the ionization radiation source in the smoke detector has no impact on whether the americium atoms are americium atoms. If the atoms have 95 protons, 95 electrons, and and 146 neutrons, then they are americium-241, and if the number of neutrons is different, they are still americium atoms in general (though different isotopes of that element). That said, I would advise against trying to collect all of the americium you can from lots of samples of smoke detectors. First off, why would you even want to do such a thing? What purpose do you have for collecting that much americium? Second off, the more you have altogether that you are exposing yourself to at once, the more radiation you will be receiving. I don't feel like sitting down and doing the math on how much americium-241 you would need to have to be dangerous or how many smoke detectors that would be. Alpha-radiation has a very low ability to penetrate materials, and even your skin can block most of it, but if, while working with it, you accidentally ingested or inhaled any americium, you would then have an alpha-emitter inside your body, which could be dangerous. If you do not know proper procedures for handling radioactive materials, and given your line of questioning I highly doubt you have formal training in radiation safety, do not do whatever project this is. --OuroborosCobra (talk) 21:22, 10 February 2021 (UTC)[reply]

What I'm talking about is the fact that, as an example, silver might not be not totally pure. It can be 99.999% pure, it can be mixed in with other metals. The purity of silver can be questioned. Same with Americium. How pure is it when its first made? I get that it turns into other metals over time but at this point, I doubt much of it has happened. And I know that it can be harmful but I do know enough to be safe. I've been learning on my own time the different levels of radiation and what's powerful enough to stop it. Besides,I have a 10 mL plastic vial. Its gonna take a while to get enough smoke detectors for Americium to be dangerous. The reason I'm doing this is because I'm an element collector. Not a professional one but still, I want to get every element I can and as pure as I can get it. UB Blacephalon (talk) 03:29, 11 February 2021 (UTC)[reply]

It sounds like the question is "what fraction of the emitter (Am plus gold plus whatever-else) is actually americium"? As a start, a 1981 ORNL report notes "The sources of ionizing radiation used in ICSOs consist of...of a 0.002-mm-thick mixture of gold and ^24lAm that is hot-forged onto a 0.2-mm-thick silver backing and covered by a 0.001- to 0.002-mm-thick gold foil."[8] So the Am/Ag is about 0.5% by volume if you can get just the emitter out of the surrounding metal structure (see photo to right).

Taken another way, the ORNL report says the source is 3–5 mm wide, so let's back-of-envelope/ballpark from there. By eye the the object in the picture looks about 20 mm diameter and 5 mm thick. That gives a volume of 1.5 cm³, for approximate mass of approximately 4 g (based on it mostly being solid aluminium, as the image-description page notes). The description says it contains 141 ng ²⁴¹AmO₂, which is about 125 ng Am. So the object is 31x10^–7% by mass ²⁴¹Am. DMacks (talk) 04:16, 11 February 2021 (UTC)[reply]

David Hahn sourced material for his experiment from smoke detectors, etc --TrogWoolley (talk) 15:20, 11 February 2021 (UTC)[reply]

February 8

A disease once called "alhimenia"

In the source Thomas W. Cardozo: Fallible Black Reconstruction Leader p.204, footnote 89, there is,

Massachusetts records show that Cardozo died in Newton April 13, 1881, of "alhimenia."

What could "alhimenia" be referring to? Bob K31416 (talk) 23:50, 8 February 2021 (UTC)[reply]

Looking at the relevant record, it's pretty hard to read. --jpgordon^{𝄢𝄆 𝄐𝄇} 00:26, 9 February 2021 (UTC)[reply]

Are there other samples of the person's writing that might be used to help decipher the writing in the image you displayed? Can you give a link? (P.S. Well done getting that image.) Bob K31416 (talk) 02:23, 9 February 2021 (UTC)[reply]

Here's the whole page from the registry. File:Thomascardoza_death_record_page.jpg It's entry 104. I just googled "Massachusetts Death Records" and it was available via one of the genealogy sites I use. --jpgordon^{𝄢𝄆 𝄐𝄇} 02:41, 9 February 2021 (UTC)[reply]

But just to add one more level of confusion: This page is, I think, a collation of individual death records, because that book you cite refers to "Record of Death No. 88115, Commonwealth of Massachusetts", so even this is a transcription of whatever the doctor wrote on the death certificate. --jpgordon^{𝄢𝄆 𝄐𝄇} 02:52, 9 February 2021 (UTC)[reply]

Just a stab in the dark here but could it be referring to malnourishment? The word alimony was in my head so I mixed it with Alhimenia and found alimonia, which I guess could be used to refer to a person's nourishment. Maybe the document writer couldn't spell in Latin? I don't know Latin, this was just a wild thought that crossed my mind. Zindor (talk) 01:14, 9 February 2021 (UTC)[reply]

Alkalemia. Abductive (reasoning) 09:42, 9 February 2021 (UTC)[reply]

That's certainly more plausible than my attempt at divination. Zindor (talk) 10:48, 9 February 2021 (UTC)[reply]

The third letter does look more like a "k" than an "h", to me. ←Baseball Bugs ^{What's up, Doc?} carrots→ 10:56, 9 February 2021 (UTC)[reply]

The closest thing in GLOSSARY OF MEDICAL TERMS USED IN THE 18TH AND 19TH CENTURIES is "Asthenia... abnormal bodily weakness or feebleness; decay of strength". Not close enough though. Alansplodge (talk) 11:57, 9 February 2021 (UTC)[reply]

Can we get a link to the image this is a clipping of? Comparison with letter shapes in recognizable words may help in deciphering. Are there more instances of undotted i's? Of k's with wide open legs? And so on. --Lambiam 11:33, 9 February 2021 (UTC)[reply]

I already provided that up above. File:Thomascardoza death record page.jpg. --jpgordon^{𝄢𝄆 𝄐𝄇} 15:47, 9 February 2021 (UTC)[reply]

There is albuminemia, both hypoalbuminemia and hyperalbuminemia. Don't know it that would have been diagnosable in 1881. Some sources say albuminuria was first described in 1884. 85.76.65.17 (talk) 13:17, 9 February 2021 (UTC)[reply]

Perhaps some compound word ending in uremia? Bus stop (talk) 14:22, 9 February 2021 (UTC)[reply]

To me it reads as “albumenia.” The term “albuminia” or sometimes “albumenia” shows up in some Google Books results from the right time period. Just from context, it seems to mean albuminuria. —Amble (talk) 16:16, 9 February 2021 (UTC)[reply]

Lots of good ideas but so far, identification of the disease seems uncertain. From my analysis of the letters, it doesn't look like "alhimenia". The h doesn't look like other h's on the page and what is supposed to be the first i is not dotted, which the writer has done consistently with the other i's on the page. (P.S. In case anyone is curious, this is related to the article Thomas Cardozo.) Bob K31416 (talk) 23:16, 9 February 2021 (UTC)[reply]

There are several examples of "bu" in birthplaces that end with "-bury" or "-burgh". (See the parental birthplace column on the facing page.) This is a good match to the supposed "hi" or "alhimenia". So our word starts with "albu-". The rest of the letters are clear, I think, so that gives "albumenia." --Amble (talk) 01:58, 10 February 2021 (UTC)[reply]

Yes, you've shown how you got the spelling correct and that goes well with your previous message that identified the disease. Bob K31416 (talk) 20:44, 10 February 2021 (UTC)[reply]

From this autopsy report in an 1845 issue of The Boston Medical and Surgical Journal it is apparent that this is the same as Bright's disease – actually more a syndrome with a range of possible causes and no longer acceptable as a diagnosis. --Lambiam 11:57, 10 February 2021 (UTC)[reply]

Good further information and support of the identification. Bob K31416 (talk) 20:44, 10 February 2021 (UTC)[reply]

To summarize, the death record entry (#104 disease, cause of death) was not "alhimenia" but "albumenia", which has also been spelled elsewhere as "albuminia"[9]. Another name was Bright's Disease but the currently used medical term is albuminuria. Thanks everyone. Bob K31416 (talk) 23:43, 10 February 2021 (UTC)[reply]

February 9

How can a ball of glass bounce higher than rubber ball?

How can a ball of glass bounce higher than rubber ball? I always thought reverse would happen. Rizosome (talk) 02:42, 9 February 2021 (UTC)[reply]

It might depend on what it's bouncing off of. Where did you see this? ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:59, 9 February 2021 (UTC)[reply]

Doesn't matter where they saw it. It's a common demonstration. And you could easily try it yourself. ApLundell (talk) 06:33, 9 February 2021 (UTC)[reply]

How would dropping them both on concrete work out? ←Baseball Bugs ^{What's up, Doc?} carrots→ 07:05, 9 February 2021 (UTC)[reply]

Probably not catastrophic, if that's what you're thinking of? Haven't you ever played with glass marbles? They'll bounce on concrete real nice. ApLundell (talk) 07:24, 9 February 2021 (UTC)[reply]

I don't recall trying to bounce them on the sidewalk. In any case, you've answered the OP's questions, and mine. Thank you! ←Baseball Bugs ^{What's up, Doc?} carrots→ 10:52, 9 February 2021 (UTC)[reply]

It would be interesting to test against a Super Ball. ←Baseball Bugs ^{What's up, Doc?} carrots→ 10:55, 9 February 2021 (UTC)[reply]

The rubber flexes and absorbs some of the energy.

A glass or steel ball will not, and so it will bounce higher than most types of rubber. here is an article that discusses it.

(Obviously, there are limits. Throw a glass ball hard enough and it will absorb the energy by shattering into a zillion pieces!)

ApLundell (talk) 06:33, 9 February 2021 (UTC)[reply]

Roughly speaking, the squishier the material, the more energy it absorbs on collision. A balloon filled with sand will not, or hardly, bounce. The energy loss is expressed by the coefficient of restitution, which is higher for glass than for rubber; see the section Colliding different materials and practical measurement. See also the articles Bouncing ball (for the physics) and Bouncy ball (for the material aspects). Squishiness is not the sole determining factor, as demonstrated by Super Balls, which are squishier than glass marbles but have a higher coefficient of restitution, about 0.85 (bouncing off concrete).^[10] A glass marble gets to only about 0.66, so the Super Ball is the higher bouncer. --Lambiam 11:12, 9 February 2021 (UTC)[reply]

I copied your question into the Google search-bar and hey presto (second result): Why a Glass Ball Bounces Higher Than a Rubber Ball. Alansplodge (talk) 11:43, 9 February 2021 (UTC)[reply]

I think another good resource for explaining this, in addition to those above, is elastic collision vs inelastic collision. In an elastic collision, all of the kinetic energy is conserved, so if a bouncing ball hit the Earth elastically, it would bounce back up with the same kinetic energy, and so would reach the same height no matter how many times it bounced (all other things being equal, such as the Earth being stationary for the purposes of this reference frame, zero air resistance, etc.). However, real bouncing balls don't actually bounce elastically, rather, they bounce inelastically. The total kinetic energy is not conserved, it is lost as some of it is converted to other forms of energy. As a result, each time a ball bounces, it has less kinetic energy than it started with before the bounce, and cannot reach the same height. A glass ball is more elastic than a rubber ball. Note that I am using the word "elastic" as it is used in physics, and not as it is used colloquially. I find very interesting how colloquial usage of terms often runs nearly opposite to their scientific usage. A rubber band is something we think of as elastic, but when a rubber ball bounces, it is further from an elastic collision than a glass ball, and we don't think of a glass ball as "elastic". --OuroborosCobra (talk) 00:37, 10 February 2021 (UTC)[reply]

M's butterfly collection

I've recently watched On Her Majesty's Secret Service, and I have one thing to say and one thing to ask about M's butterfly collection (which is briefly shown at about 44 minutes into the movie): first of all, I'm pleased that none of them frightened me (because none had an appearance, and especially a color pattern, similar to that of Papilio glaucus or P. garamas); and second of all, does anyone happen to know what are the species of those pretty little (or not so little) critters? Because I couldn't positively identify any of them (except the one on the far right, which Bond identified as an unusually small Nymphalis polychloros, although it might just as well have been its smaller cousin), except that the orange one on the middle left looks like some kind of fritillary (don't know the species, though), and the black one with hindwing spurs on the lower right looks similar to the male Papilio polyxenes (but I know it can't be, because it doesn't have that bold yellow band on the trailing edge). Can anyone identify any of these species? 2601:646:8A01:B180:714F:5D88:96DA:F4B4 (talk) 12:53, 9 February 2021 (UTC)[reply]

I'm curious to know why you find those 2 species scary-looking. ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:32, 9 February 2021 (UTC)[reply]

I don't know if it's the same user or not, but there was a semi-frequent refdesk IP-user that had a severe butterfly phobia. I had a room-mate in university who also got freaked out by them. Phobias are weird things. Matt Deres (talk) 15:13, 9 February 2021 (UTC)[reply]

That does sound vaguely familiar. In any case, I wonder if it's connected with Trypophobia in some way. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:07, 9 February 2021 (UTC)[reply]

Lepidopterophobia is a thing. Pity Vladimir Nabokov never wrote a novel about a person with a butterfly phobia. -- Jack of Oz ^{[pleasantries]} 21:21, 9 February 2021 (UTC)[reply]

Which redirects to Entomophobia. I can see having some fear (or at least a very healthy respect) concerning bees or ants. But are there any venomous butterflies or moths? ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:25, 10 February 2021 (UTC)[reply]

To the knowledge of this former amateur lepidopterist, no adults are, although a few species of caterpillars have irritant hairs or are poisonous if eaten. However, part of the definition of Specific phobias including Zoophobias is that they are irrational, and may stem from experiences in early childhood. My late grandmother had a phobia about kittens. {The poster formerly known as 87.81.230.195} 2.125.74.203 (talk) 07:13, 10 February 2021 (UTC)[reply]

Regarding my phobia of those 2 species (and all others which look like them): yes, I am the same user who had previously reported a severe phobia of swallowtail butterflies -- but based on my original research over the past 2-3 years, I can now be more precise and say that I have a phobia of only tiger-striped (or zebra-striped, like Protographium marcellus) swallowtails (and then only those with a perceived size bigger than about 3-3 1/4 inches, so for example Papilio canadensis and P. zelicaon are too small to scare me, and P. machaon can only scare me at near-maximum size), or species which are exceptionally large (such as P. cresphontes), but not solid black ones of reasonable size like P. troilus (which I actually kind of like, as a matter of fact). In other words, it's not the tails -- it's the size and the stripes! As for why, who knows -- maybe a butterfly with a similar appearance snapped its wings open at me when I was too young to remember (probably a N. polychloros -- they do that and they're pretty big, and the only swallowtail native to where I lived then was P. machaon, which does not do that), or maybe I had a close encounter with a P. multicaudata and was so terrified by its yuge size that I began to fear all butterflies with a similar appearance (I remember when I first saw a tiger swallowtail, which I think was a P. rutulus based on its size, I was not any more fearful of it than I was of any other large butterfly at the time -- that is, since it was some distance away, I was apprehensive but not acutely frightened -- it was only later that tiger swallowtails became especially scary for me). Anyway, that's not what the question was originally about, was it? 2601:646:8A01:B180:B17C:FCE8:58C0:4A1 (talk) 02:27, 11 February 2021 (UTC)[reply]

Thanks for explaining. And note that you brought it up. ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:06, 11 February 2021 (UTC)[reply]

A rather foggy YouTube clip of M's collection is here. Alansplodge (talk) 19:13, 9 February 2021 (UTC)[reply]

February 10

COVID origin

What is the reason WHO says the coronavirus “most likely” originated in animals. (Alternatively:) Why isn’t it just as likely it originated in humans? MBG02 (talk) 23:18, 10 February 2021 (UTC)[reply]

This paper says that a very similar virus has been found in bats, but is different enough that COVID would have split off from it 50 years ago. This suggests an origin in animals. --142.112.149.107 (talk) 03:42, 11 February 2021 (UTC)[reply]

Many human coronaviruses have their origin in bats, but rats are culprits too. See diagram and Coronavirus#Origin.--Shantavira|^{feed me} 09:30, 11 February 2021 (UTC)[reply]

See also Origin of SARS-CoV-2 - 26 March 2020 from the WHO, which also points to the initial outbreak in the infamous Huanan Seafood Wholesale Market where all kinds of wild and domestic creatures were kept and slaughtered in appalling sanitary conditions. Alansplodge (talk) 11:52, 11 February 2021 (UTC)[reply]

Bats are special in that they aggregate in large numbers for long periods in confined spaces, while having an immune system that protects them more than is usual in other families.^[11][12] (These two may be related.) In any case, that makes them a perfect breeding ground for developing mutations in infectious pathogens of respiratory illnesses, such as several coronaviruses. --Lambiam 13:14, 11 February 2021 (UTC)[reply]

February 11

photons between quarks in protons, neutrons, and mesons- what energies?

I’ve been told, if I understand it right, that the 3 quarks in a proton interact both through the strong force and electromagnetic force, with the quarks exchanging gluons for the strong force. Should the quarks also be exchanging photons for the electromagnetic force? If so, what are their energies? Are they even higher than the energies of gamma rays from nuclear fusion or fission? Do they compare with the photon energies from particle accelerators?Rich (talk) 07:15, 11 February 2021 (UTC)[reply]

They will be exchanging virtual photons. Dja1979 (talk) 17:50, 11 February 2021 (UTC)[reply]