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June 6

Health risk of taurine consumption

Realistically, how worried should people be about the health risks of consuming taurine as a supplement? I only ask because half the literature says they find it helpful and beneficial at some unknown dosage, while the other half says it is potentially carcinogenic and could contribute to colon cancer. As a layperson, I find this very confusing. Some of the literature says it could be simply a matter of dosage, but nobody seems to know what the safe or harmful limits are. Can anyone offer some risk analysis devoid of emotion? Should we avoid anything with taurine in it, or not worry at all about it? Viriditas (talk) 01:27, 6 June 2024 (UTC)

As far as Wikipedia is concerned, WP:MEDRS applies. That means that the minimum quality level for WP:RS making medical claims are systematic reviews indexed for MEDLINE (there are some exceptions from this indexation, but generally speaking MEDLINE is the gold standard). tgeorgescu (talk) 03:29, 6 June 2024 (UTC)

Our article states that there is no good clinical evidence that taurine supplements provide any benefit to human health, Why pay for useless supplements? The human body naturally produces a large amount of taurine, far more than one can reasonably take in as a supplement. There is increasing evidence that taurine actually plays a role in preventing cancer.^[1] Any carcinogenicity of supplements can only be due to their being fake, or a lack of quality control in their production.  --Lambiam 07:23, 6 June 2024 (UTC)

The underlying issue is that large doses of taurine are added to energy drinks. Nobody seems to know why. A current study is looking at an association between energy drink consumption and the rise in colon cancer in young adults.[2] Viriditas (talk) 08:23, 6 June 2024 (UTC)

Even disregarding any potential carcinogenic risks, there are enough studies that show damaging health effects of high consumption levels of energy drinks.^[3][4]  --Lambiam 18:28, 6 June 2024 (UTC)

¼ liter of my favorite energy drink has 80 mg caffeine, while adults usually consume up to 400 mg caffeine per day. And I use the energy drink totally without sugar. tgeorgescu (talk) 18:59, 6 June 2024 (UTC)

The energy drink thing may be related; most energy drinks contain vitamin B12. There is a concern that (mega)dosing B12 in excess of daily requirements carries with it a slight increase in risk of cancer due to B12 containing cobalt, which is both a heavy metal and has a trace of radioactive cobalt-60. Abductive (reasoning) 20:25, 6 June 2024 (UTC)

Thank you, that's helpful. I just read the comments by the epidemiologist on that topic, and while my reading might be flawed, they seemed to indicate that dosage and tobacco smoking played a significant role in the risk. Viriditas (talk) 22:02, 6 June 2024 (UTC)

Real skepticism cuts both ways. Taurine is in human breast milk, evidence of benefit of at least one energy drink exceeding risk. :-) But our article has imho excessive, even dubious doubt in that section on its conditional essentiality or benefit for infants, and thus its common use in another energy drink. Doubt that appears to stem from OR or opinion rather than the source, which says e.g. "Thus the new data provide further support for the view that taurine is a conditionally essential nutrient for the preterm infant" & that ethical considerations seem to prevent further research.John Z (talk) 03:57, 7 June 2024 (UTC)

June 9

Weigeltisaurus species clarification

Is this Weigeltisaurus reptile in this family Rhynchocephalia. Would that statement be true to say. Its for this article Johannes Weigelt. There is source that states it but I don't know how accurate it is. scope_creep^Talk 21:23, 9 June 2024 (UTC)

While Weigeltisaurus flourished in the Late Permian, our article on the order Rhynchocephalia states that the oldest record of the group is dated to the Middle Triassic. According to this chronology, a gap of several million years separates them.  --Lambiam 07:21, 10 June 2024 (UTC)

Right. I'll leave the Rhynchocephalia bit out and only mention the Weigeltisaurus bit, since I don't understand it. Thanks @Lambiam: scope_creep^Talk 08:52, 10 June 2024 (UTC)

June 11

Can we agree on what the rule of the Council of Nicaea actually was?

Banned user
The following discussion has been closed. Please do not modify it.
Transferred from Humanities desk Let me highlight Jack's comment above: ...What is or is not legal is a matter for courts or legislatures to determine. Not the media, not individual partisan politicians, not the man in the street, not the reasonable man, and not random commentators (on Wikipedia or anywhere else). -- 22:23, 6 June 2024 So why is Wikipedia still saying Wedding of Prince Harry and Meghan Markle#Preceding private ceremony "The Church of England sources commented that this was not a legally recognised marriage ceremony, which requires two witnesses", citing journalist and radio commentator Camilla Tominey, who screamed down the telephone I WILL NEVER WRITE THE STORY that Camilla and Charles' wedding ceremony was a "non-qualifying ceremony" (i.e. void), following up with a stream of invective which only ended when she was cut off? And as the words "Registrar General" are eiusdum generis with the list of occupations provided by Jack, why is the linked article still saying "the Registrar General, Len Cook, determined that a civil marriage would in fact be valid"? The articles are so full of editorialising that it is best not to read them and go to [5] and [6] instead. Needless to say the "impediments to marriage" listed in the licence do not apply to the marriages of non-royals, because they were abolished by the Marriage Act which specifically states that its provisions have no applicability whatsoever to royal marriages. 92.25.129.245 (talk) 16:45, 8 June 2024 (UTC) Readers may be interested in a dream I just had. Following the inception of the discussion (Wikipedia:Reference desk/Humanities#June 7) about al-Biruni and the Byzantine calendar, before I went to bed last night (30 James, the day before the date marked with this year's "golden number" (11), 1 Eloise), I looked for the new moon and saw a very slender crescent low in the north-west. In the dream, I was at work and was told that Camilla Tominey and another presenter had arrived to interview me. The male presenter remained outside and Camilla came in. She was aggressive and incoherent, and after a while an aide entered and bundled her out. I heard him say as he took her away "You're not on the programme any more. We're changing the presenter." Then the other presenter came in and said "You're going to be on the programme - ATV." As we left, he commented "You're casually dressed." I said "Shall I go home and change into something more formal?" and he said "We'll dress you at the studio." Then he asked an assistant "She's carrying a handbag, take it from her." I thought "This is for the general election." Outside there were a number of vehicles. Beside one of them a woman staff member was restraining a short man with his hands behind his back. I woke up at this point and went downstairs. It was 1:30 AM. I switched on the radio and this song began playing: [7]. 92.12.79.187 (talk) 15:42, 9 June 2024 (UTC) As a matter of historical interest, one grouse the Muslims had about the imposition by the Caliphs of the new, unintercalated Islamic year for administrative purposes to replace the 365-day Zoroastrian year previously used in Persia was that it was shorter, which meant that the land tax would come round before the harvest had been collected! The Caliphs relented and reinstated the araji (land-tax) year for fiscal purposes. But then another problem presented itself. The Muslim era began in AD 622 with the Hegira (flight) - the Persians later fixed the beginning of this era on Friday, 19 March. The Zoroastrian year needed periodic readjustment because it was itself on average six hours shorter than the Julian. Al-Biruni notes that there was a double adjustment of the start of the araji year during the reign of Yazdegerd I (AD 399-420). An araji era was introduced dating from AD 621. In a further recalibration, the Yazdegerdi era, still used by the Zoroastrians (Parsees), dates from the accession of Yazdegerd III on 16 June AD 632, so the Yazdegerdi era is eleven years behind the araji. In AD 895 there was another double readjustment of the start of the araji year. It moved from 1 Frawardin (12 April) to 1 Khordad (11 June), referred to as 11 Haziran (I think the Turks call June by this name to this day). Today's Byzantine date (Monday, 2 Eloise), marks the imminent arrival of the Jewish Feast of Weeks (Pentecost), observed on the 6th of the corresponding Jewish month. It is barred from falling on Tuesday, Thursday or Saturday, and slots in this year this coming Wednesday (4 Eloise). Orthodox Whitsun is not till Sunday, 23 June (15 Eloise), because of the rule that Orthodox Easter falls on the Sunday after the Wednesday after the date of the Paschal Full Moon (14 Miri) between 1800 and 2099 inclusive, a sharp contrast with the Roman Catholic Church (but not it's Byzantine arm), which likes to time its Easter festivities to fall in the week after the "Purim Full Moon". The Orthodox consider the Catholics to be in error and they are right - the Council's direction was that the Easter full moon must not precede the equinox, but in 1582 Gregory XIII directed that it must be the first after the equinox. This led to his calendar being banned in Orthodoxy. 2.30.124.132 (talk) 15:43, 10 June 2024 (UTC) Some common Serbian names feature in the story. This article includes the following points: In addition to the issue of calendar reform, the Council of Constantinople (1923) also discussed possible union with the Anglican church and second marriage for priests Vladimir Dimitrijevic, a conservative author, said the Council of Constantinople was among the greatest mistakes of the Orthodox Church in the 20th century The author is Jovan Trpkovic. An article by M S Dimitrijevic and others includes these points: The Serbian delegation came to the Congress with a proposition for calendar reform authored by Maksim Trpkovic. He proposed the intercalation rule that the secular years in centuries which when divided by 9 have remainders of 0 or 4 will be leap years The general opinion of the participants was that the better solution was to retain the Julian calendar and only delete thirteen days... The information was duly sourced and added to Julian calendar. This led to one editor demanding that the contributor be banned from Wikipedia for "inserting false information into articles" because "if thirteen days are excised from the Julian calendar it is no longer Julian." He further demanded that articles be pre-emptively semi-protected to prevent editors removing any unsourced falsehoods added by others. His campaign was successful and false information, for example that the Greek government introduced the Gregorian calendar in 1923, is embedded in articles all over Wikipedia. The original Serbian proposal was in fact a proposal that the calendar already legislated by the Greek government should now be adopted by the Orthodox Church. As to where the Greek government got its calendar from, it's described here although Trpkovic (who proposed it in 1900) denied all knowledge of Barnaba Oriani's calendar. Another example is the claim that "The reform of the calendar was authorised by a canon of the Council of Trent in 15.." (the last two digits of the date of the alleged canon are something of a movable feast, since they change periodically). 92.19.71.221 (talk) 15:14, 11 June 2024 (UTC) References

June 12

Grignard Reagent with Haloalkane

The reaction between a Grignard reagent (${\ce {RMgX}}$) and an alkyl halide (${\ce {R'-X}}$) gives what product? I see some sources saying there would be substitution reaction thus forming ${\ce {R-R'+MgX2}}$, whereas other source says there would be transmetallation thus forming ${\ce {R'MgX +R-X}}$. Thanks for your time, ExclusiveEditor _{Notify Me!} 12:19, 12 June 2024 (UTC)

The WP article on Grignard compounds itself states that "Grignard reagents do not typically react with organic halides, in contrast with their high reactivity with other main group halides. In the presence of metal catalysts, however, Grignard reagents participate in C-C coupling reactions." Also in this article there is a diagram of different reactions that show the reaction between R'-X and RMgX to yield the C-C coupling product (where R' should be a carbonyl-like moiety such as benzyl or allyl). Logically, the MgX⁺ cation should strongly bond with the halogen atom of R'-X during the reaction, resulting in a very stable salt MgX₂. The more stable the products are, the more favorable a reaction pathway is. 2402:800:639D:9B0A:C9C4:BA57:2B8:DC89 (talk) 14:01, 16 June 2024 (UTC)

Yes, but as you state, it happens in presence of metal catalyst (transition metal). My question doesn't mention our reaction having any such catalyst. ExclusiveEditor _{Notify Me!} 19:11, 21 June 2024 (UTC)

On otherhand, the transmetallation reaction requires that both two of the reactants must be organometallic compounds (i.e, contains at least a metal-carbon bond), which is not the case with one of your reactants R'-X.Vanadium-3065 (talk) 14:08, 16 June 2024 (UTC)

When forming a Grignard reagent by the standard method of adding an alkyl halide like EtBr to Magnesium turnings suspended in ether, controlling the exotherm by the rate of addition, there will be a point where the halide is being added to material that contains substantial amounts of EtMgBr. If coupling (i.e. the substitution reaction) were fast, the main product would be butane and it would be impossible to form a good yield of the Grignard reagent! My trusty "Advanced Organic Chemistry" by Jerry March says that you can deliberately encourage the coupling reaction by adding thallium (I) bromide, Cr, Co or Cu chlorides or various other reagents, depending on the type of Grignard reagent you have already formed. The mechanism is via the R-Metal intermediate which decomposes via free radicals. Mike Turnbull (talk) 15:08, 17 June 2024 (UTC)

@Vanadium-3065: You may be right. But then the question is still half answered. It still does not say if R-R' will be formed or not. If not transmetalation, there could be a metal-halogen exchange as stated by DMacks below. ExclusiveEditor _{Notify Me!} 19:13, 21 June 2024 (UTC)

@Vanadium-3065, Michael D. Turnbull, and 2402:800:639D:9B0A:C9C4:BA57:2B8:DC89: To clarify, I am not an advanced chemistry student, so I don't realize things which really require deep insights. However one thing I would mention is that the statement that R-R' would not be formed but transmetallation would happen is written in Clayden (available at pg 189 at pdfs available online.). Maybe this would help clear any confusion, or if the publisher should be informed that the strict language that R-R' would not be formed is wrong. Reply appreciated, ExclusiveEditor _{Notify Me!} 16:13, 21 June 2024 (UTC)

The Clayden statement is correct and corresponds to what I said above. In order to get R-R' you need to add a transition metal. Mike Turnbull (talk) 17:22, 21 June 2024 (UTC)

I just saw Kumada coupling and read that page of Clayden again. So we need some transition metals like Ni/Pd to act as catalyst to form carbon-carbon bond (R-R'). If it is not available, then transmetalation takes place in equilibrium? ExclusiveEditor _{Notify Me!} 18:18, 21 June 2024 (UTC)

The logic of that Clayden statement seems incorrect (or circular at best). It says that substitution "does not work because of transmetallation. The two alkyl bromides and their Grignard reagents will be in equilibrium with each other so that, even if the coupling were successful, three coupled products will be formed." (my underlining). That doesn't sound like a reason why it doesn't work, just potential evidence that it doesn't work and not even stating that the evidence is true. And isn't this really metal–halogen exchange (swapping M and X on the R groups) rather than transmetallation (M and M', like the Schlenk equilibrium)? DMacks (talk) 18:19, 21 June 2024 (UTC)

So I think my question could be summarized as, what product do we get, if we conducted Kumada coupling without any catalyst, and the answer supposedly is that we get transmetalation (or metal–halogen exchange as said by DMacks) per Clayden. It is only if we use some transition metal like Ni/Pd as catalyst, that we get a carbon-carbon bond (R-R'). ExclusiveEditor _{Notify Me!} 18:41, 21 June 2024 (UTC)

Check a SpringerLink reference

http://doi.org/10.1007/978-94-017-9861-7_22

Does anyone have access to this? If so, does it make any reference to the diet or hunting behaviour of Euthyrhynchus floridanus? Such claims were added without reference to this insect's article four years ago ([8]), and later someone dumped in a reference to this book. Nyttend (talk) 21:15, 12 June 2024 (UTC)

I don't think so. The closest I can find is "However, only a few notes about its life history on the field are known (Avila-Núñez et al. 2009 )" The reference is "Avila-Núñez JL, Ortega LDO, Pisarelli MPC (2009) Un caso de depredación de adulto de Gonodonta pyrgo Cramer 1777 (Lepidoptera: Noctuidae) por Euthyrhynchus floridanus(Linnaeus 1767)(Heteroptera: Pentatomidae: Asopinae). Entomotropica 23:173–175". (Btw, you should be eligible for Wikipedia Library; that's how I could access the book).--Wrongfilter (talk) 21:46, 12 June 2024 (UTC)

@Nyttend: You can get its access at Wikipedia Library, publications at springer are available there. However, for this one there is no mention of things that were claimed, in that chapter at least, so there removal is legitimate. ExclusiveEditor _{Notify Me!} 16:41, 21 June 2024 (UTC)

June 13

Synchronous orbit

Diagram showing my possibly flawed understanding of astronomic poles of a body with a synchronous orbit.

I think I understand the different poles (near pole, far pole, leading pole, trailing pole) and associated hemispheres of a body with a synchronous orbit, but I'd like to double-check. I've drawn (badly) a diagram showing my understanding of these things (see right), and I've given a shot at explaining it at Rhea (moon):

Rhea is tidally locked and rotates synchronously; that is, it rotates at the same speed it revolves (orbits), so one hemisphere is always facing towards Saturn. This is called the near pole. Equally, one hemisphere always faces forward, relative to the direction of movement; this is called the leading hemisphere; the other side is the trailing hemisphere, which faces backwards relative to the moon's motion.

Is this right, or am I missing something? Cheers, Cremastra (talk) 21:35, 13 June 2024 (UTC)

I have the impression some assumptions are missing from the definitions in our articles Poles of astronomical bodies and/or Synchronous rotation. Without additional assumptions, the aspect of the satellite as seen from the body it circles is subject to possibly significant libration. One assumption is that the orbit of the satellite is circular. The other is that its axis of rotation is aligned with the normal to the orbital plane – in other words, its poles of rotation and orbital poles coincide. Under these assumptions, your diagram corresponds with the definitions given. The intersection of the green–yellow band and the red–blue band is a pole of rotation and the three axes defined by the various kinds of pairs of opposite poles are at right angles to each other.  --Lambiam 18:35, 14 June 2024 (UTC)

Because of the curve of the orbit, the line between the true rearmost and forward-most points is inward from the geometric center of the satellite. The article implies that this difference is ignored in practice. —Tamfang (talk) 20:23, 18 June 2024 (UTC)

June 14

Australian fizzy cans

What is the average mass of an (empty) Australian fizzy can of the typical size? It's easy to find pages talking about the amount of liquid a typical can holds (375 ml), but I can't find anything about the mass of the aluminium. Drink can gives a US figure, but that's not useful because cans here are a different size, and also it's a really rough estimate, being derived from a US-EPA source that says "assume 34 cans per pound". Nyttend (talk) 02:49, 14 June 2024 (UTC)

14.9 grams, according to the Australian Aluminium Council. [9] Figure is from 2001 and the trend seems to be downward so perhaps they're lighter today.  Card Zero  (talk) 04:41, 14 June 2024 (UTC)

An empty 330 ml beer can in New Zealand is 14-15 g. I expect an Australian can would be the same.-Gadfium (talk) 05:13, 14 June 2024 (UTC)

Card Zero, thank you! Information added to the drink can article. If I had a large quantity, I suppose I could just weigh them and divide by the number, but I don't have a good scale, and I don't have room to hold a huge number for a representative sample anyway. Plus, I'd rather take them (and little cans, and plastic bottles, etc.) to redeem the deposit without amassing a huge quantity. Nyttend (talk) 05:21, 14 June 2024 (UTC)

About how much would a full can of Foster's weigh? ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:23, 14 June 2024 (UTC)

Don't ask an Australian that question. They never drink Fosters. HiLo48 (talk) 06:09, 14 June 2024 (UTC)

TV ads in America used to say that Foster's is Australian for "beer". Evidently that is not altogether true? ←Baseball Bugs ^{What's up, Doc?} carrots→ 06:51, 14 June 2024 (UTC)

Not in the last 40 years. The same goes for throwing another shrimp on the barbie. We call them prawns, not shrimps. HiLo48 (talk) 23:31, 14 June 2024 (UTC)

Some Foster's ads, for your possible amusement. The comments are telling. [10] Also, Americans may not know shrimps from prawns, but we know all about barbie. There was a major movie about it last year. :) ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:09, 15 June 2024 (UTC)

Google says it's the typical size of 375ml, so add in the can and we're at about 390ml, just like Coca-Cola or Carlton Draught or Victoria Bitter. I know much more about alcohol containers than I did before Victoria introduced container deposit last year...never had an idea that Coke-diluted whiskey existed (what's the point of diluting a distilled beverage?), let alone was sold in cans with US-specific branding like Bourbon County, or was sold in 200ml cans. But I don't remember seeing Foster's cans in any of the neighbourhoods where I go on foot and collect discarded containers. Nyttend (talk) 05:37, 14 June 2024 (UTC)

Regarding your question, Nyttend. (i) Many people find the taste/mouthfeel of some undiluted spirits over-strong. (ii) Sometimes one wants to drink a larger volume and a weaker ABV than the undiluted spirit; with less intensely flavoured spirits, such as vodka, this can effectively produce 'alcolohic dilutant' (I used to be fond of screwdrivers, for example). (iii) The combination of the spirit and dilutant can result in quite different new and desirable tastes: this is partly chemical – for example, a single drop of water added to a glass of single-malt whisky can have a very noticable effect, I'm told. {The poster formerly known as 87.81.230.195} 151.227.226.178 (talk) 17:47, 18 June 2024 (UTC)

Thank you! As a non-drinker, this is all strange to me. In particular, I assumed that the point of drinking distilled beverages was experiencing the alcohol intensely. Also wouldn't have guessed that the diluted beverage would taste anything other than a proportionate mix of the flavours, e.g. in the water-in-single-malt-whiskey example, I figured it would merely weaken the taste, like putting water into milk or fruit juice. Nyttend (talk) 19:49, 18 June 2024 (UTC)

The reason I ask is that in Monty Python at the Hollywood Bowl, they were throwing what appeared to be full Foster's cans into the crowd. It occurred to me that if they were actually full, that could be dangerous. ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:51, 14 June 2024 (UTC)

Who is "Professor Cleveland Abbe" (Meteorology)

I might as well ask here as someone may be bored and can help solve a mystery. I recently added information published by "Professor Cleveland Abbe" to History of tornado research#19th century (specifically this article). He was the editor of Volume 25, Issue 6 of Monthly Weather Review, published in June 1897. However, after reading the "General Characteristics" (basically the introduction) to the academic paper, it doesn't actually say where Mr. Abbe is a professor, just that his title is "professor". At the time, Monthly Weather Review was run by the U.S. federal government (United States Weather Bureau), so he had to be some meteorological scientist.

It's a long shot, but if someone wants to try to check around for a scientist/professor named "Cleveland Abbe" in the late 1800s/early 1900s, maybe the university he is a professor of could be located. I honestly, don't expect an answer to this, but asking others never hurts. The Weather Event Writer (Talk Page) 05:10, 14 June 2024 (UTC)

Cleveland Abbe has an article. :D  Card Zero  (talk) 05:16, 14 June 2024 (UTC)

Ultimate facepalm moment. LOL. Thank you Card_Zero! The Weather Event Writer (Talk Page) 05:16, 14 June 2024 (UTC)

Scientists disappointed by a shared Nobel prize

Are there cases known when a scientist longed for the Nobel prize so much that he was disappointed by even a Nobel prize he had to share? --KnightMove (talk) 07:39, 14 June 2024 (UTC)

George Santos, but he got over it by the time he got his fourth one. Clarityfiend (talk) 10:05, 14 June 2024 (UTC)

Art for blind people

I have just read the Fantastic Four comic and, before the usual superhero stuff gets started (an invasion of vampires, go figure), there's a brief slice of life intro in a museum. Alicia Masters, one of the characters, is blind, and the museum has reproductions of famous fine arts that can be touched, so that blind people can enjoy them as if reading braille (see here). Is that really a thing, or was the author making it up like the rest of the fantasy and sci-fi stuff? Cambalachero (talk) 13:30, 14 June 2024 (UTC)

Here's a couple of articles [11][12]. Sean.hoyland (talk) 15:30, 14 June 2024 (UTC)

A tactile reproduction of Roy Lichtenstein's Whaam! for the Tate Modern gallery in London, which offers "touch tours" for the visually impaired. Alansplodge (talk) 12:35, 16 June 2024 (UTC)

""Angry Small Boy" is a bronze statue of a nude infant boy modelled by Norwegian sculptor Gustav Vigeland ca. 1928."

Sculptures are sometimes exhibited in public places where they can be touched by blind people. The example shown stands in an Oslo park and its bronze surface is kept polished by visitors who often stroke it (either for art appreciation or just "good luck"). Philvoids (talk) 16:21, 17 June 2024 (UTC)

No wonder the boy's angry. Clarityfiend (talk) 08:49, 18 June 2024 (UTC)

June 17

Unit usage

1. Is the height of clouds and flying animals from earth's surface measured in meters or feet in most countries? I have seen using feet as primary units in this wiki's articles.
2. Are distances on association football pitch, such as length of goal kick, measured in meters in most continental European countries?
3. Are rink and equipment sizes in ice hockey measured in metric units in most continental European countries?
4. Is there any country that measures American football field sizes in metric units?

--40bus (talk) 21:01, 17 June 2024 (UTC)

In aviation, height is often measured in feet, even in countries that otherwise make little use of Imperial or US customary units. This would apply to clouds, but flying animals don't come up too much in aviation, unless your name is Sully Sullenberger. Jc3s5h (talk) 21:07, 17 June 2024 (UTC)

In aviation, altitude is usually measured in flight levels, with one flight level corresponding to the barometric pressure difference of 100 feet under normal conditions. Using barometric altitude is due to the fact that it is easier to measure well, and good enough to ensure vertical separation of aircraft. That on FL corresponds to 100ft is a historical relic, but air traffic is extremely conservative. --Stephan Schulz (talk) 21:19, 17 June 2024 (UTC)

Regarding this, is there any English-speaking country that has metric flight levels? --40bus (talk) 21:34, 17 June 2024 (UTC)

According to the FAA's Aeronautical Information Manual (page 231 of the PDF) in the US feet are used up to but not including 18,000 feet MSL (that is, above mean sea level). At and above 18,000 MSL flight level is used. Moving on to page 601 of the PDF, there is a complex discussion of setting the aircraft's altimeter, but essentially instructs to use the current actual barometric pressure if below 18,000 feet MSL. But at or above 18,000 feet MSL all operators will set 29.92 inches of mercury, which is considered the standard setting. The manual doesn't say so, but I've been taught that below 18,000 feet the chief concern is colliding with terrain, and above that the chief concern is colliding with other aircraft. The altimeter setting is chosen to minimize the risk in the respective altitude ranges.

Other countries may have a transition altitude other than 18,000 MSL. Jc3s5h (talk) 21:53, 17 June 2024 (UTC)

Outside the US, American football is virtually nonexistent, and supporters are likely to be Americans. NFL Europe says that the league gave an additional point for field goals of 50 yards, not 45 metres. Nyttend (talk) 08:03, 18 June 2024 (UTC)

User:40bus, when you say American football field sizes, do you mean measuring American football fields specifically, or anything roughly that size? Rugby league and rugby union, which are related to American football, are played on fields a bit larger than American football, and their dimensions are measured in metres. Nyttend (talk) 19:39, 18 June 2024 (UTC)

Heights of clouds, birds, buildings, anything are measured in metric in most of the world. The only exception is aviation, which shifted in most of the world post-World War 2 from metric to British/American units. It had something to do with the post-war dominance of the British and American aviation industry. Historical aircraft (pre-1945), but also many modern gliders, from Europe typically have altimeters in metres and airspeed indicators in km/h. PiusImpavidus (talk) 10:48, 18 June 2024 (UTC)

Meteorology tends to use the same units as aviation (or at least they did when I worked in the field, over 20 years ago), resulting in a weird mess of systems. So heights and altitudes in feet (unless we were dealing with things more than about 15-20km up, when we switched to km). Visibility in metres, but long distances in nautical miles. Speed in knots. Temperature in Celsius. Pressure in millibars / hectopascals. Iapetus (talk) 14:45, 18 June 2024 (UTC)

Of course, the nautical mile is a very different matter from anything else non-metric, since it's based on the distance of a minute of latitude, because such a figure is very easy to measure on maps. The nautical mile article notes that it was sanctioned for use by France and that other metric countries have defined it in metric terms (and makes an uncited claim that many metric countries approved its use), which is rare or unique for pre-metric units. Nyttend (talk) 19:39, 18 June 2024 (UTC)

I have seen using feet as primary units in this wiki's articles.

We have unit conversion templates that should make it possible to see the units of your choice in any given article. They haven't yet been applied consistently to all articles, but you can update them yourself if you encounter places where they're missing. -- Avocado (talk) 22:26, 19 June 2024 (UTC)

Football

I found that in articles of major association football matches use yards first in distances and lengths of shots, even macthes played in completely metric countries. Should they use meters first? --40bus (talk) 13:47, 19 June 2024 (UTC)

How do the news media cover it? ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:44, 19 June 2024 (UTC)

I meant that this wiki's articles do that. --40bus (talk) 18:41, 19 June 2024 (UTC)

Do Wikipedia's articles conform to the way the news media cover it? ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:56, 19 June 2024 (UTC)

Extracting energy from the Earth's rotation

I've been thinking about the Focault pendulum, and that gave me an idea. For simplicity, assume I put a gyro on a freely rotating platform, exactly at the North Pole, with the axis of the gyro parallel to the ground (and hence the equatorial plane). As I understand it, the gyro-mount would rotate once every 24h relative to the Earth - the gyro remains stable, the Earth is rotating under it. What would now happen we connect a generator to the platform (possibly via a gearbox to get a bit above 1rpd). Would it be possible to extract useful amounts of energy from this construct? I actually have no idea how to calculate this... --Stephan Schulz (talk) 21:11, 17 June 2024 (UTC)

If you wish to extract energy from the Earth's rotation, there are simpler ways to do it. AndyTheGrump (talk) 21:16, 17 June 2024 (UTC)

Tidal power draws mainly on the energy of the Moon's orbit. A windmill blown by a hurricane is an example of drawing power via Coriolis effect from the Earth's rotation. Philvoids (talk) 21:25, 18 June 2024 (UTC)

Yes, but those are boring. I want the mad scientist solution. --Stephan Schulz (talk) 21:20, 17 June 2024 (UTC)

I'm not sure, but aren't the present day Focault Pendulum systems powered using an electromagnet so that they keep going indefinetely? Getting energy from this would never be more than the energy inserted in it using the magnet. Rmvandijk (talk) 08:37, 18 June 2024 (UTC)

The lazy answer is: thermodynamics says no. Without transporting angular momentum from the Earth to anywhere off Earth, the only energy that can be extracted is the rotational energy of the flywheel and you won't get more than what you used to spin up your gyroscope.

Now it's clearly possible to extract energy from the gyro-mount in the way you described. The gearbox will apply a torque to the gyro-mount, trying to put the gyro's spin axis vertical, but it's restricted in its movement, so there will be another torque perpendicular to both the gyro's spin axis and the vertical, causing the gyroscope to precess with the Earth's rotation. But it's possible to tune this torque such that the gyro's precession rate will be half a revolution per day, so that neither the torque nor the angular speed of the mount relative to Earth will be zero, so that power can be extracted. It's not immediately obvious how this energy can be extracted from the rotational energy of the spinning gyroscope, as that requires a torque along the gyro's spin axis. I suspect it has something to do with precession of the Earth itself. PiusImpavidus (talk) 11:53, 18 June 2024 (UTC)

Certainly, the gyro's spin axis is mechanically restricted to a flat plane, then the gyro and the Earth are torquing the gearbox and doing work in that plane. Operating it at low speed on a magnetic suspension reduces windage and friction. Hmmm, of course, for it to be an effective energy source the rate of work extracted from their rotations must be greater than the rate of energy needed in maintaining its operation. Yet whenever I stand up or lay back down, the Earth's rotational energy and momentum are redistributed between my body and the Earth. Thus I don't see how or why energy and momentum conservation is an issue with this clever invention. Modocc (talk) 23:27, 18 June 2024 (UTC)

In other words, the angular momentum and mass-energy of the entire Earth is conserved, but the energized gyro(s), the rotating platform and its gearboxes are redistributing it, hence the Earth is both the source and repository of the energy. Moreover, this idea is related to the Coriolis effect which is very small, yet it would be simple enough to demonstrate its principles on a much smaller scale: simply substitute a spinning wheel for the planet. A second free-spinning wheel placed on the axle serving as the platform per the OP's specs, should act as a regenerative brake. Modocc (talk) 22:11, 19 June 2024 (UTC)

June 18

If atomic number was known in 1869, would the unknown elements (as of that time) be discovered earlier?

In 1869, Mendeleev predicted that there exists elements with atomic masses 44, 68, 72, 100, and they corresponding to atomic numbers 21, 31, 32, 43, unfortunately, at that time, only atomic mass was known and atomic number was not known, and according to the article Discovery of chemical elements, the unknown elements as of 1850 are the elements with atomic numbers 2, 10, 18, 21, 31, 32, 36, 37, 43, 49, 54, 55, 59, 61, 62, 63, 64, 66, 67, 69, 70, 71, 72, 75, 81, …, if atomic number was known in 1869 (or 1850), would these elements be discovered earlier (by finding the elements with missing atomic numbers)? 220.132.216.52 (talk) 06:01, 18 June 2024 (UTC)

You seem to be asking us to speculate, which we don't do here. However, I don't see how that information would lead to any elements being discovered earlier. Shantavira|^{feed me} 09:24, 18 June 2024 (UTC)

Mendeleev only correctly predicted elements 21, 31, 32, 43 and did not predict elements 2, 10, 18, 36, if atomic number was known in 1869, then maybe Mendeleev would also predict elements 2, 10, 18, 36? 220.132.216.52 (talk) 10:38, 18 June 2024 (UTC)

Imagine a document is sent to Mendeleev through a time machine, saying, "All elements have an atomic number. For hydrogen it is 1, for lithium it is 3, ..., and for thorium it is 90. Your four predicted elements have atomic numbers 21, 31, 32 and 43." How would this information have been useful to Mendeleev, or any scientist of his time, in making predictions?  --Lambiam 20:00, 18 June 2024 (UTC)

"Any scientist of Mendeleev's time" will include Bohr (16), Rutherford (2) and van der Broek (1) where their ages at Mendeleev's prediction are in brackets. It's unlikely that any of them will benefit from a magical receipt of numbers without explanation that do not fit then-known atomic weights. There is just a tiny probability that your tipoff causes baby van der Broek who is destined to arrange the periodic table by proton numbers at age 41 in 1911 (4 years after Mendeleev's death) to do so earlier. Philvoids (talk) 21:13, 18 June 2024 (UTC)

OP must be thinking about a Bell number for the combinations and arrangements leading to atomic numbers. Yet Mendeleev would simply have not been Mendeleev himself (and more than probably someone else would have grabbed the document instead). Here is a view described more similar to Medeleev own private domain of thinking. And yet ions themselves... --Askedonty (talk) 21:27, 18 June 2024 (UTC)

Mendeleev should find the missing atomic numbers (2, 10, 18, 21, 31, 32, 36, 37, 43, 49, 54, 55, …) and try to predict the properties of the elements with these atomic numbers. 42.76.70.59 (talk) 05:29, 19 June 2024 (UTC)

Atomic mass are not consecutive numbers, but atomic numbers are. 42.76.70.59 (talk) 05:29, 19 June 2024 (UTC)

What you really need for many of these discoveries is to push the invention of the spectroscope earlier. Otherwise, it is very difficult to find elements like Ga, which don't have any common high-content minerals. Note that element 43 remained elusive for a while even after the discovery of atomic numbers: this is a similar case where having the theory doesn't mean you'll find the element, since you need technology that isn't there yet (in this case, artificial transmutation).

There are a few cases that could get away without it. Henry Cavendish came pretty close to discovering argon, and if he really did it, I can see the noble gases as already being known by Mendeleev's time. Among the lanthanides, europium in particular has a +2 oxidation state that could have been used to find it much earlier. Double sharp (talk) 07:18, 19 June 2024 (UTC)

Gas non-giants

Planet says that planets are classified as "a giant planet, an ice giant, or a terrestrial planet". This doesn't appear to leave room for Earth-size gas planets. Why can't they exist? Or can they exist theoretically, and we just don't know of any? Nyttend (talk) 08:01, 18 June 2024 (UTC)

Could the gas dwarf form in the first place? One theory of formation is that solids have to coalesce first to make a planet that can attract gas to make a gas giant. SO small objects will not form. But if a ball of gas the size of Earth existed would it be stable and survive? Probably not as the density would be lower and so gravity is lower. It would have to be far from the Sun to stop solar wind erosion. Graeme Bartlett (talk) 09:28, 18 June 2024 (UTC)

e/c You need a lot of mass (gravity) to keep that gas together, and with too little mass any atmosphere would disappear (Mercury, Venus, etc). Earth is just the right size. Shantavira|^{feed me} 09:31, 18 June 2024 (UTC)

Though Venus has a significant carbon dioxide atmosphere. So perhaps you could have a planet made from carbon dioxide. Though with pressure this would transform into diamond and metallic oxygen in the core. Graeme Bartlett (talk) 09:58, 18 June 2024 (UTC)

Between ice giants and terrestrial planets, there's room for ocean worlds. PiusImpavidus (talk) 12:17, 18 June 2024 (UTC)

See also Super-Earths. {The poster formerly known as 87.81.230.195} 151.227.226.178 (talk) 17:51, 18 June 2024 (UTC)

Based on the data we have, planets generally obtain a Neptune-like atmosphere once they cross two Earth masses.

On the other hand, in a way Venus is close to what you want. Its atmosphere even goes supercritical as it approaches the surface. :) Double sharp (talk) 07:22, 19 June 2024 (UTC)

June 19

Carnivore diet

(Disclaimer: I don't want to put my cat on any kind of diet, in fact I don't have a cat, so this is purely a science question). I was surprised to find a ton of online search hits about putting cats on vegan diets This one mentions that you at minimum have to include some supplements like taurine that come only from animal sources. Thus, the diet is not 100% vegan.

My question is whether there are at least potential workarounds such as protein synthesis, that would allow putting obligate carnivores like cats on purely plant diets and keeping them healthy? Question is inspired by a discussion elsewhere about "impossible burgers", which supposedly give meat-like nutrition to humans. There must be something missing though, that humans can do without but cats cannot. Thanks. 2601:644:8501:AAF0:0:0:0:78AE (talk) 09:28, 19 June 2024 (UTC)

Most mammals, including humans, can biosynthesize taurine. Felids lack this ability. Taurine can be synthesized in a chemical production process not involving animal sources; see Taurine § Synthesis.  --Lambiam 06:09, 21 June 2024 (UTC)

Buoyancy question

What's the minimum concentration of an aqueous table salt solution which will ensure that a human being will float regardless of his/her body type, even with all his/her muscles fully contracted (assuming standard temperature and pressure)? Disclaimer: this is not a homework question. 2601:646:8082:BA0:649B:7753:3C84:C70D (talk) 10:28, 19 June 2024 (UTC)

0%. Since water is 997kg per cubic meter and the average density of the human body is 985kg per cubic meter. 41.23.55.195 (talk) 11:37, 19 June 2024 (UTC)

Obviously you haven't been to the Dead Sea or the Great Salt Lake. Clarityfiend (talk) 13:53, 19 June 2024 (UTC)

If you are in a swimming pool you can descend to the bottom by contracting your muscles, which I guess decreases your body's volume. I guess that is what OP was referring to. Question is how much salt it takes to make this impossible. I can say 3.5% or so is not enough, since you can also do that in the ocean. 2601:644:8501:AAF0:0:0:0:78AE (talk) 16:45, 19 June 2024 (UTC)

I have never been able to float. --User:Khajidha (talk) (contributions) 17:58, 19 June 2024 (UTC)

Assume the "Jesus position" with an arched back. It works for me, and I'm no swimmer. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:55, 19 June 2024 (UTC)

That's not what I was asking -- the context here is a panic attack causing a person to sink (think something similar to the floundering in the water scene in Titanic, but minus the hypothermia), so obviously voluntary techniques won't work in this context. 2601:646:8082:BA0:649B:7753:3C84:C70D (talk) 23:05, 19 June 2024 (UTC)

Sure. I was talking to Khajidha. But knowing the technique can help conquer a panic situation. ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:01, 20 June 2024 (UTC)

I don't have panic attacks in water (my one and only severe phobia has to do with something else entirely) -- I was asking this simply out of curiosity. So, at what salinity level would a person not sink even if he/she panics and suffers a muscular spasm all over his/her body? 2601:646:8082:BA0:649B:7753:3C84:C70D (talk) 02:30, 20 June 2024 (UTC)

According to this,[13] the Dead Sea has the highest salinity in the world, at 34 percent, making it virtually impossible to sink. So that at least puts a frame on your question. And this[14] suggests an experiment you could do. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:26, 20 June 2024 (UTC)

I'm aware of the Dead Sea -- however, my question was about the lowest salinity level at which a person would float under all circumstances, which is probably quite a bit lower than that in the Dead Sea. And does an egg have the same maximum density as a person with all his/her (I'd go with his, since a woman's body probably has a lower density than a man's) muscles fully clenched? 2601:646:8082:BA0:649B:7753:3C84:C70D (talk) 05:57, 20 June 2024 (UTC)

Well if you want this to apply to all people you will need to know the density of the most dense human body. That is probably one with deflated lungs, no gas in the intestines and a very low proportion of fat. And do we allow someone who at a barium meal? Graeme Bartlett (talk) 07:04, 20 June 2024 (UTC)

Google has various opinions. Here's one:[15] ←Baseball Bugs ^{What's up, Doc?} carrots→ 08:03, 20 June 2024 (UTC)

IP editor: you may be interested in this calculator which provides the density of saline solutions. Note that the answer you seek depends on the temperature of the water. By setting various concentrations of salt, you can find out the density of the resulting solution. You still have to decide what "floating in all circumstances" means to you. Mike Turnbull (talk) 10:12, 20 June 2024 (UTC)

Most of the short-term volume variation in humans comes from the lungs. Depending on which muscles exactly contract, the volume of the lungs may increase or decrease. Most people have a reflex to fill their lungs when they unexpectedly enter the water, making them positively buoyant.

Also, people who unexpectedly enter the water usually wear clothes. Clothes tend to be negatively buoyant when wet, but can trap a lot of air. When panicking, you can quickly squeeze that air out or your clothes, making you sink. And some clothes wake it very difficult to swim. That's why we teach our children in basic swimming lessons to swim with light clothes on, but also to get their clothes off if too heavy. Panicking people might forget to get their clothes off. PiusImpavidus (talk) 12:39, 20 June 2024 (UTC)

OK, User:Baseball Bugs FTW with the most helpful answer this time around -- thanks! 2601:646:8082:BA0:649B:7753:3C84:C70D (talk) 03:48, 21 June 2024 (UTC)

If it's any help I can sink and lie flat on the bottom of a swimming pool by just letting some air out but I can't do that in the sea. NadVolum (talk) 10:26, 21 June 2024 (UTC)

How can DHA be a primary structural component of the brain, cerebral cortex, skin & retina?

Antioxidants? Do brain lipids ever go rancid while someone's still alive? Sagittarian Milky Way (talk) 23:52, 19 June 2024 (UTC)

Fats may go rancid, usually by exposure to air and light. Fats are esters. DHA is not an ester, it is a (fatty) acid.  --Lambiam 04:55, 20 June 2024 (UTC)

How would brains be a delicacy if the fat was free acids? 12% lipids. And even if it was free acid the main problem's double bonds oxidizing probably eventually making it gum like oil paints' triglyceride molecules tangling and polymerizing. Sagittarian Milky Way (talk) 11:33, 20 June 2024 (UTC)

Whose brains are you eating? ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:02, 20 June 2024 (UTC)

I don't eat any flesh but I've heard you can even buy brains 'n' beans in a can in the South (I've seen a pint or quart of pig blood in a container in a NYC grocery store so could doesn't necessarily mean common). Brains 'n' beans is calorie-dense, if you wolf it down cause it's delicious it becomes junk food. Sagittarian Milky Way (talk) 12:26, 20 June 2024 (UTC)

Rose brand pork brains in milk gravy are readily available at grocery stores 'round my neck of the woods (Hickory, NC). Oh! WHAAOE! eggs and brains. I also see sites selling them fresh or freeze dried.-- User:Khajidha (talk) (contributions) 14:42, 20 June 2024 (UTC)

Sounds about as appetizing as the Beverly Hillbillies' staple: possum innards. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:03, 20 June 2024 (UTC)

That's probably it, eggs 'n' brains, not beans. Sagittarian Milky Way (talk) 17:58, 20 June 2024 (UTC)

Is the question about DHA or about lipids?  --Lambiam 19:08, 20 June 2024 (UTC)

June 20

Are scientists sure that agriculture only started with the Holocene?

Could there have been agriculture hundreds of thousands of years ago before the last ice age?Rich (talk) 08:12, 20 June 2024 (UTC)

Some group of dinosaurs could have had agriculture millions of years ago before they were all wiped out for all we know. But see the big box at he top of this page, one of the things it says is "We don't answer requests for opinions, predictions or debate" NadVolum (talk) 08:19, 20 June 2024 (UTC)

Very unlikely. I suggest you read Mannion, A. M. (5 December 1995). Agriculture and Environmental Change: Temporal and Spatial Dimensions. Wiley. ISBN 0471954780. or similar. Agriculture depends on the domestication of crops and animals and its main centres were in areas of the world that were not covered in ice. Hence we would see archaeological traces whenever that had occurred. Mike Turnbull (talk) 09:29, 20 June 2024 (UTC)

Ant–fungus mutualism is often considered a form of agriculture, and it developed millions of year ago. --Amble (talk) 17:23, 20 June 2024 (UTC)

Humans were slow starters. ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:28, 21 June 2024 (UTC)

Scientists can never be sure about their theories. A good theory explains the patterns they observe. But errors can creep in, both in the process of obtaining observations and in recording them. Also, in a laboratory experiment one can perhaps make direct uninterpreted measurements, but in the field observations require interpreting the raw data, and the interpretations themselves depend on theories whose validity can also be subject to doubt. A pattern may be manifest while not being due to some underlying process but emerging by pure chance. And, finally, there is always the possibility of new observations uprooting a generally accepted theory. As to human agriculture, the currently best available explanation of the observations is that sedentary agriculture was an innovation that emerged in a few places and spread out from these during the Neolithic.  --Lambiam 19:46, 20 June 2024 (UTC)

There may have been some earlier domestication attempts in the warmer periods on either side of the Last Glacial Maximum. I recall hearing that Zohary wondered if wheat didn't go back 20,000+ years, and lately there's been some talk about olives and pine nuts, which of course wouldn't show much in genetic studies as they are long-lived trees. I myself wonder about Vicia palaestina (whose stub I created). What makes this hard to tease out is that if it occurred, it occurred in the same area as the successful domestication events, thus masking the clues. Abductive (reasoning) 06:16, 21 June 2024 (UTC)

Please see

If you are interested in genetics, please see Wikipedia:External links/Noticeboard#Human mitochondrial genetics and share an opinion about whether the proposed ==External links== would be interesting or valuable to readers. WhatamIdoing (talk) 22:50, 20 June 2024 (UTC)

June 21

Noctilucent clouds

How high (in angle) do noctilucent clouds have to be to be seen? Do they have to appear outside the lighter area of the sky during nautical twilight? I've been watching clouds before last few sunrises but I'm not sure if i'm just observing high altitude cirruses, they are whitish but not bright at all like in the pictures. Other (lower) clouds stay dark for a long time after that, almost until sunrise. I can't tell if they disappear after sunrise because there's a lot of humidity haze or maybe still Sahara's smog, and my phone is terrible at taking pictures at twilight. Please don't just tell me to read the page, it hasn't helped me with this. 31.217.31.107 (talk) 02:21, 21 June 2024 (UTC) They were visible from around 3.30 to 4.30 here (30min ago) in Zagreb, whatever they are. They weren't that sharp like on the pictures. 31.217.31.107 (talk) 02:57, 21 June 2024 (UTC)

Under the right conditions you should be able to see them at any angle, wherever they are hanging out, from the horizon to directly overhead.  --Lambiam 05:48, 21 June 2024 (UTC)

I saw them at up to 45 degrees up (the 'height' of the polar star here). They didn't really look like the pictures in the article, they were more faint and blurry although they were lighter than the sky all along while low clouds are darker than the sky that close to sunrise. I think they could look that way because of heavy light pollution lately and high humidity but I'm still not sure if they weren't just cirruses because low clouds are always lighter than the sky near midnight, there's enough light pollution. Is there any way to be sure? 31.217.31.107 (talk) 05:58, 21 June 2024 (UTC)

On the only occasion I've seen noctilucent clouds, they were up to 4 degrees above the horizon (half the altitude of Capella at that time), almost straight north. At the same time, the sun was also almost straight north, 14 degrees below the horizon. Not nautical twilight, but the sky was still fairly bright and the noctilucent clouds were in the bright part. With those angles, the radius of the Earth and some high-school geometry, you should be able to calculate the minimum altitude of the clouds to be in sunlight. If that's more than about 12 kilometres, they can't have been ordinary cirrus clouds. Use a planetarium program like Stellarium (open source) to find the position of the sun at the time you observed the clouds. PiusImpavidus (talk) 08:11, 21 June 2024 (UTC)

Lunar Standstill

A lunar standstill is supposed to happen tonight. I've read the article's simplified description and I'm still confused. So, is this correct? In my own words...

During a lunar standstill, the Moon does not actually stand still, nor does it appear to. All this means is that tonight the Moon will rise at its most northeastern point and set at its most northwestern point. Period. It's not something you can go out at a specific time to observe, see something different, the event ends, and you go about your evening. It's an event that takes "all" (air quotes) night (the time the moon is out).

Do I have that right?

Thanks! †dismas†|^(talk) 12:14, 21 June 2024 (UTC)

I wasn't aware of this, this is quite interesting (if you're into that sort of thing). "Standstill" refers to (the lack of) motion in declination, i.e. the north-south coordinate (equivalent to latitude on earth), and is equivalent to the solstices. Summer solstice was yesterday (sun at its northern-most point), we also have full moon tonight, and since the full moon is opposite to the sun this means that moon is at its southern-most point (not northern!). In addition the moon is at its lowest point below the ecliptic, so that in sum we have a major lunistice. In principle these are all point events but the changes over the course of a night are so small that it is effectively an all-nighter. Where I am, the moon will only be 12 degrees above the horizon when it culminates in the south around midnight. --Wrongfilter (talk) 13:31, 21 June 2024 (UTC)

According to this article, we're not at the absolute extreme tonight, though. The situation is quite complicated and the extremes differ for moonrise and moonset, compare the graphics in that article. --Wrongfilter (talk) 13:44, 21 June 2024 (UTC)

For about one year every 18.61 years your hometown Moon rise/peak/set paths are more extreme than any other time (north/south, rises and sets unusually left/starboard, also low/high if you're between latitudes 29 and 62 or so. North or south of 29 you'll never see a shorter hometown Moon shadow than one of these fortnightly standstills in the next year or so probably near one of the standstills near a half moon near one of the next 2 equinoxes (the Full Moons can be up to 1.2 Moon radii less extreme but the c. 19 year cycle is 20 radii to minus 20 radii) Sagittarian Milky Way (talk) 14:01, 21 June 2024 (UTC)

The cycle peaks early 2025 I believe but cause complexities records can be up to seasons away. Records like rightmost Full Moon rise for your location between about 2006 and 2043 or lowest Full Moon path of a night in that timeframe, might be tonight or about 355 days in the future. High Full Moon records are probably December 2024, some other records are probably near an equinox in 2025 or late 2024. If you want I can get each major record to the nearest millisecond (false precision?) for any location on Earth. From what might be the most accurate possible way (https://ssd dot jpl dot nasa dot gov/horizons/app.html#/, there's also other interfaces like email and telnet but for this you don't need the relatively few email/telnet-only tools) Sagittarian Milky Way (talk) 14:27, 21 June 2024 (UTC)

From 74W 40¾N 0ft the highest Moon center in the future of anyone alive is 77.753639° the year 2025 April 3rd 6:05:02.857pm (ellipsoidal coordinates). The highest before that was 2006 Mar 7th 18:56:52.857 77.753848°. The sky was pretty dark for this one as it's always near half moon so can't be too close to midnight. The highest before that was 1950 October 3 6:07:53.010am 77.782823°. These follow the obliquity Milankovitch cycle which is slow enough that a new record doesn't happen every 18.61 year cycle as you go back in time. So the highest since about 3X thousand BC was about 10,000 years ago. Sagittarian Milky Way (talk) 21:19, 21 June 2024 (UTC)