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January 29[edit]

Tracing a recent scientific paper[edit]

A few years ago, a paper was published in a pretty prestigious journal that took a scathing dig at the publish-or-perish culture in science and the resulting often-useless research. In their field, there was a proliferation of little-novel papers on generating composites of two or more elements, subjecting them to a set of standard tests, and reporting the results. The authors explained how and why such an approach had nothing to offer except the publication of C(118,2) + C(118,3) + ... papers! I recall that the paper attracted immense attention from pop media and probably, had a title with the f-word.

Now that I have forgotten all recognizable details about the paper (journal/author/field), what was it? TrangaBellam (talk) 14:36, 29 January 2023 (UTC)Reply[reply]

Probably in a journal of American Chemical Society! TrangaBellam (talk) 14:43, 29 January 2023 (UTC)Reply[reply]
@TrangaBellam I used Google Scholar to look for a few of the keywords in your question. I don't think I found the exact paper you had in mind but this one is open-access and has lots of references. You could play around in Scholar to come up with other possibilities. Mike Turnbull (talk) 15:23, 29 January 2023 (UTC)Reply[reply]
I know of that but failed to retrieve the paper. This is far from the paper, I have in mind. TrangaBellam (talk) 15:36, 29 January 2023 (UTC)Reply[reply]
Resolved courtesy a colleague from another department.
The article is Wang, Lu; Sofer, Zdenek; Pumera, Martin (2020-01-28). "Will Any Crap We Put into Graphene Increase Its Electrocatalytic Effect?". ACS Nano. 14 (1): 21–25. doi:10.1021/acsnano.9b00184. ISSN 1936-0851. TrangaBellam (talk) 17:22, 29 January 2023 (UTC)Reply[reply]
These guys are hilarious! They actually used "crap" (guano) in their sarcasmfest! Clarityfiend (talk) 00:11, 31 January 2023 (UTC)Reply[reply]

January 30[edit]

Zombie muscle[edit]

We don't answer requests for opinion or debate.
The following discussion has been closed. Please do not modify it.
  • Zombie muscle ... comments? .... 0mtwb9gd5wx (talk) 06:23, 30 January 2023 (UTC)Reply[reply]
    It's well referenced. Do you have an actual question? Comments about article content can be made on its talk page. Shantavira|feed me 09:23, 30 January 2023 (UTC)Reply[reply]
    Giving this snippet of trivia a subsection (with a tabloid title!) of its own calls the notion of undue weight to mind. The terminology of "freshly killed muscle meat" is questionable – while the organism is dead, some of the tissue may still be alive (see e.g. Organ donation).  --Lambiam 10:21, 30 January 2023 (UTC)Reply[reply]

Philvoids (talk) 14:04, 30 January 2023 (UTC)Reply[reply]

Dichroic prism?[edit]

Dichroic prism

Hi, a quick question about the article Dichroic prism, which defines its topic as "a prism that splits light into two beams of differing wavelength (colour)", is illustrated by the image on the right, which is a featured picture. However, it looks to me like there are quite a few more colours than just two in this image. Can anyone explain this? I would have asked on the article talk page, but it doesn't seem like it's a well-watched article so don't know if I'd get an answer. Cheers  — Amakuru (talk) 14:35, 30 January 2023 (UTC)Reply[reply]

@Amakuru: The photographer is @XRay:, who is more active on Commons at c:User_talk:XRay. DuncanHill (talk) 14:43, 30 January 2023 (UTC)Reply[reply]
You can find a small explanation at the file page at Commons. ;-) --XRay (talk) 15:05, 30 January 2023 (UTC)Reply[reply]
@XRay: thanks for the response. The description at Commons says "To explain what is shown: The prism lies on a black cardboard with a rough surface to make the light visible. The light from a flashlight with white light is focused by a lens (telephoto lens) onto the prism from below (right), with a small part of the white light passing the prism." - is this what you're referring to? I'm still confused from this explanation, though, what would make it a dichroic prism. There are clearly more than two colours being emitted. Thanks  — Amakuru (talk) 17:57, 30 January 2023 (UTC)Reply[reply]
It is an explanation of the creation of the image. It is not a physical experiment. In the center you can see the prism, whose description is dichroic prism. --XRay (talk) 18:35, 30 January 2023 (UTC)Reply[reply]
Color-separation prism assembly with dichroic mirrors (white light beam from above)

I'm not familiar with the term dichroic prism, but here's a photo I took of a color separation prism assembly I designed (for the Foveon Studio Camera). It has dichroic mirrors between the prism pieces, to reflect and transmit different wavelength bands. It looks to me like the "dichroic prism" has a variety of different dichroic mirrors on its external and internal surfaces. Dicklyon (talk) 10:49, 31 January 2023 (UTC)Reply[reply]

January 31[edit]

Why does the late Holocene Susquehanna mouth look like New England?[edit]

If Chesapeake Bay is the drowned valley of the Susquehanna River then why does the river enter so far from the apex and look like a canal instead of the typical drowned river shape of the rest of the area? Sagittarian Milky Way (talk) 07:41, 31 January 2023 (UTC)Reply[reply]

Sorry, I don't follow your question. Can you clarify? --Jayron32 10:00, 31 January 2023 (UTC)Reply[reply]
It would be helpful if you linked to an image showing what you refer to, but River engineering, including canalization and channelization, and Dredging could be factors. {The poster formerly known as 87.81.230.195} 90.221.194.253 (talk) 14:39, 31 January 2023 (UTC)Reply[reply]
There was no river engineering. According to this, "The Susquehanna is so old that the mountains and valleys formed around it, rather than the river shaping the valleys." Abductive (reasoning) 17:02, 31 January 2023 (UTC)Reply[reply]
Au contraire, there's considerable engineering in the form of dams along it; consider the Conowingo Dam which lies just a few dozen kilometers from the mouth of the river. Water flow along the Susquehanna (like most east-coast rivers) has been heavily controlled and engineered for well over a century by now. --Jayron32 17:08, 31 January 2023 (UTC)Reply[reply]
Not in the way User:Sagittarian Milky Way was asking, no straightening. The Susquehanna is not navigable, and it drops steeply, so the linearity is natural. Abductive (reasoning) 17:15, 31 January 2023 (UTC)Reply[reply]
Yes, that much is true; the Susquehanna largely follows the course that it has for thousands of years. However, I still am not sure what Sagittarian Milky Way was asking, which is why I asked them to clarify. I'm still not sure what they mean by "looks like a canal" and "apex" and the terminology they are using. I have crossed the Susquehanna many times, at a large number of places along its course. At no point does it look like a canal, IMHO. I have looked at it many times, and I have looked at a great many canals as well. The Susquehanna doesn't look particularly like a man-made waterway anywhere I have seen; especially not near the mouth. The views off of the Millard E. Tydings Memorial Bridge don't look particularly canal-like, nor do the views from the Tidewater Grille in Havre de Grace, Maryland, which has a lovely back deck right on the river. --Jayron32 17:31, 31 January 2023 (UTC)Reply[reply]
Hudson Canyon.jpg
Okay canal is an exaggeration. On Google Maps (not Street View) it resembles some of the river mouths in New England (especially the Thames) more than it resembles most of the Chesapeake Bay and North Carolina Sound estuaries. i.e. it doesn't look like the Potomac or Patapsco estuary. New York Bight says the very tip of this embayment is the New York Bight Apex. I guess if you squint you can sort of see the valley turn left at the last minute so it follows the Susquehanna instead of the Elk or North East River but it sure does look like one of those rivers is where the main vein should come from. Maybe the Delaware once drained there aggrandizing those minor Susquehanna tributaries? Sort of like how Glacial Lake Ontario once augmented the Hudson River discharge making it wider than if the ice age never happened (this Niagara of water also stopped the Hudson from draining through the exact tip of the bay by creating a strait through Statenlong Island). Sagittarian Milky Way (talk) 07:14, 1 February 2023 (UTC)Reply[reply]
A possible explanation is that it is that the "drowned river" effect runs out at that point. The Chesapeake is not just a drowned river due to sea level rise, it is because of the Chesapeake Bay impact crater. The bolide impact cracked all the limestone underlying the whole area, allowing continuous dissolution of the substrata as water infiltrates. This causes slow and steady subsidence, which may end at the "apex", as you put it, far from the epicenter. Abductive (reasoning) 10:28, 1 February 2023 (UTC)Reply[reply]
The reason that the Susquehanna is the main river feeding into the area near the north of the bay (but not the northernmost point; which is arbitrary anyways, the fact that the bay continues north of the mouth of the Susquehanna is meaningless, and the northernmost point is not the "apex" in any meaningful sense), is that the Susquehanna is the river with the largest basin in that area. The rivers that empty in further north are rivers like the Elk River (Maryland), which drains a relatively small area. Given the size of the wide Susquehanna Valley, it all has to get to the sea somehow, and the Susquehanna is it. The reason why the mouth is relatively straight and not very estuarine is that the Susquehanna is a relatively fast flowing river (or was before extensive engineering and flood control) given that it changes elevation relatively quickly. It doesn't really meander. Before the formation of the Chesapeake Bay, it likely had a proper estuary and delta region near its mouth, but all of that is currently under Hampton Roads now. --Jayron32 17:36, 1 February 2023 (UTC)Reply[reply]
Interesting. The estuariness also peters out on the Carolina coast at about the same distance from the crater, maybe not a coincidence. Sagittarian Milky Way (talk) 20:12, 1 February 2023 (UTC)Reply[reply]
The Carolina Coast is very estuarine. Much of the sounds inside of the Outer Banks is marshy, brackish, and otherwise perfectly typical of an estuary. The mouths of places like the Neuse River and the Tar/Pamlico River and places like that are as typically estuary as you are going to find. The Neuse has a 40 mile long tidal estuary system that starts at about New Bern and continues to the main body of the Pamlico Sound; a similar geography exists on the Tar/Pamlico starting at about Little Washington, and on the Roanoke/Chowan rivers before they reach the Albemarle, etc. The Carolina coast is very different from what you describe. --Jayron32 12:43, 2 February 2023 (UTC)Reply[reply]
The Fall line is probably relevant too. While the Susquehanna doesn't have a distinct break with an attendant city the way the Potomac and dozens of other rivers along the East Coast have, it has a fast, steady fall from Harrisburg to the bay that would tend to keep it straight if no other geological processes interfere. The Susquehanna spreads its falls along the whole stretch, is quite shallow and wide, and has many small rapids or riffles instead of one big drop. It is very un-canal-like. Acroterion (talk) 12:55, 2 February 2023 (UTC)Reply[reply]
Contrast the Hudson River, most of which below Albany is a glacial fjord, very deep, and tidal to Albany. There was no glacial influence for the Susquehanna, which is not navigable to any significant extent. Acroterion (talk) 13:00, 2 February 2023 (UTC)Reply[reply]
PART of the Carolina coast is very estuarine. After awhile it starts getting less estuarine though some is unavoidable as the Atlantic Coastal Plain is very flat. Myrtle Beach looks very different from Pamlico Sound on a road map. Sagittarian Milky Way (talk) 17:31, 2 February 2023 (UTC)Reply[reply]
The river mouths of places in South Carolina look pretty much exactly like the places I described above if you are, you know, standing there looking at it. Myrtle Beach doesn't because Myrtle Beach is not a river outlet; there is none there. Go to Georgetown, South Carolina, and the mouth of the Pee Dee River is surrounded by the kind of brackish water marshlands you find in estuaries. That's the first river mouth you find in South Carolina. You would know that if you go to Georgetown and look around. You keep saying things which are wrong, and then trying to qualify your wrongness by saying more wrong things. Please stop that. --Jayron32 12:01, 3 February 2023 (UTC)Reply[reply]
Sure if I ever stand there (I bet it's idyllic right before the extra bad South-only dew points and pest species start) it'd look like a similar mouth in "NC lagoon" probably all the way to the horizon in every direction (which is as little as 3-3.5 miles). But instead of assuming I can't tell the difference between X and opposite X and nitpicking language it seems obvious I must've always been referring to some aspect of the south Carolinas coast that's different from the bigger, wider indentations further north. Probably the bigger, wider indentations! I always wondered why Delaware Bay, Chesapeake Bay and some NC things like Ablemarle are bigger and wider than anything in SC, GA or East FL ds and who knows maybe it's an asteroid cracking limestone. Sagittarian Milky Way (talk) 20:52, 3 February 2023 (UTC)Reply[reply]

February 1[edit]

Animals, insects, trees in snow[edit]

All those places where temperature is extremely negative, how do animals survive? I am not talking about Polar beer, penguin. I once saw a picture in national geographic where a Canadian eskimo was in igloo in snow and he was covered in mosquitoes. Why those mosquitoes did not freeze to death?

And how do trees survive brutal cold. Trees can die due to poisoning, forest fire then how do trees survive such cold, where humans have to put on so much thermals, gloves, jackets, coats. Stargty6 (talk) 17:32, 1 February 2023 (UTC)Reply[reply]

Hi Stargty6! Trees survive brutal cold because of their bark. According to the National Forest Foundation, it states Bark provides insulation and protection against freezing and cracking during the winter. It isn't just the bark, however. The trees drop their leaves to reduce water loss.
Now for the mosquitoes. For the female mosquitoes, they survive by using a form of hibernation called diapause. According to the Passport Health, it states The key to survival for female mosquitoes is a form of hibernation called “diapause.” As cold temperatures settle in, females fatten up approximately 10 times their usual fat accumulation and enter diapause. Not only that, but mosquitoes also enter indoors to survive from the cold (but most times IMO they're going to be really annoying in your houses as they sting bite and create itch spots.) Tails Wx 17:47, 1 February 2023 (UTC)Reply[reply]
@Tails Wx They bite, not sting. Bazza (talk) 20:03, 1 February 2023 (UTC)Reply[reply]
Oops, I did not think of "bite". Thank you, Bazza 7. Tails Wx 20:43, 1 February 2023 (UTC)Reply[reply]
Actually, to "bite" us, mosquitos first saw a hole into one's skin, through which they then insert a bundle of needles, including a hollow one to suck up blood while another hollow needle drips in mosquito saliva to make sure it will itch like hell.[1] Calling this "biting" instead of "stinging" is a somewhat arbitrary choice.  --Lambiam 10:33, 2 February 2023 (UTC)Reply[reply]
To be strictly accurate, the mosquito saliva isn't "to make sure it will itch like hell" but "saliva contains substances that keep our blood flowing". Without the saliva the blood would quickly congeal and Mrs Mosquito wouldn't get the blood she needs for her eggs. Itching is a by-product felt after she's flown safely away from slaps by aggrieved victims. Martin of Sheffield (talk) 10:45, 2 February 2023 (UTC)Reply[reply]
@Lambiam The link I gave, and others leading from it, are fairly clear it's a bite. Is there an interesting WP:ENGVAR difference in the definition of "bite" and "sting"? Bazza (talk) 13:12, 2 February 2023 (UTC)Reply[reply]
IMHO, a bite involves the use of mouthparts. --Jayron32 14:13, 2 February 2023 (UTC)Reply[reply]
The idiomatic term in English is "bite". But the basic sense of "biting" is to cut into something by clamping one's teeth, which is very different from what mosquitos do. So how did it become "bite" in English? In French one says, more to the point, piqure de moustique, literally "mosquito sting", and in Italian likewise puntura di zanzara.  --Lambiam 15:04, 2 February 2023 (UTC)Reply[reply]
La piqûre actually is better translated as "poke" or "prick"; it is also used when describing injections, which actually better describes BOTH what a bee and a mosquito do. The French is better translated as "mosquito prick" or "mosquito injection" rather than "sting". The sensation of "sting" is cuisant en français. --Jayron32 15:28, 2 February 2023 (UTC)Reply[reply]
Albeit mosquitoes don't bite with teeth, they do it with their mouthparts and they do it to eat. I think that's reasonably distinguished from a "sting", which is an injection of venom with the purpose of harming the recipient rather than gaining calories from them, at least immediately. (A sting might be used to incapacitate the victim, after which they would be a source of calories, but that would be a separate step.) --Trovatore (talk) 02:50, 3 February 2023 (UTC)Reply[reply]
I've always wondered if there really is a biome band of mildest mosquito season. From what they say it sounds like midsummer mosquitoes eat you alive in the boreal forest of North America (and tundra?). Sagittarian Milky Way (talk) 20:26, 1 February 2023 (UTC)Reply[reply]
Of course, not all trees drop their leaves; see How Do Conifers Survive the Cold?. Alansplodge (talk) 23:25, 1 February 2023 (UTC)Reply[reply]
And in Australia, the Snowgum, or Eucalyptus pauciflora. HiLo48 (talk) 00:28, 2 February 2023 (UTC)Reply[reply]
One of the few eucalypts that will actually grow in England. Alansplodge (talk) 22:21, 2 February 2023 (UTC)Reply[reply]
In North America, several species of hardwood trees also keep their leaves; some are only located in places where winter weather is rare or very mild, like the Quercus geminata a live oak, though there are some hardwood trees that you can find in colder climates that have real, cold, freezing winters, that also keep their leaves, such as several common species of Magnolia, as well as American Holly, which is widespread in the eastern third of the U.S. Usually, these kinds of trees have very thick, leathery leaves which perhaps protects them in freezing weather. A magnolia leaf and a holly leaf are both very unlike a maple or an elm leaf. --Jayron32 17:36, 3 February 2023 (UTC)Reply[reply]
Among significant populated places, the only truly mosquito-free place is Iceland. Per Mosquito#Distribution, "Mosquitoes are cosmopolitan (world-wide): they are in every land region except Antarctica[67] and a few islands with polar or subpolar climates. Iceland is such an island, being essentially free of mosquitoes.[87]" Also noteworthy is that not all mosquitoes feed on humans. Per Mosquito#Host animals, "Many, if not all, blood-sucking species of mosquitoes are fairly selective feeders that specialise in particular host species", which is to say you may live in an area which has plenty of mosquitoes, but which don't feed on human blood. There are also mosquitoes which don't feed on blood at all, see Toxorhynchites for one such genus, although there are many others. --Jayron32 14:18, 2 February 2023 (UTC)Reply[reply]
Mosquitoes bite you even in the city sometimes but the taiga and tundra biting season seem worse I wonder why. Tropical and subtropical biting seasons are also probably worse and sometimes transit malaria, Zika, dengue, yellow fever, West Nile etc. West Nile virus did start homegrown American transmission with New York City mosquitos but it probably started there cause it has lots of intercontinental planes and ships and was first found in 1930s Uganda as far as anyone knows. Sagittarian Milky Way (talk) 18:00, 2 February 2023 (UTC)Reply[reply]
That largely has to do with the fact that pathogens are mosquito specific, a specific species of mosquito is only able to survive in a specific environment, and only specific mosquito species feed on specific humans. In order to get, say, Yellow fever, you need to be bitten by an Aedes aegypti (or a few other related species) of mosquito which is infected. And those don't live in taiga or tundra. Dozens of species do live in the arctic, but they don't carry yellow fever. --Jayron32 11:55, 3 February 2023 (UTC)Reply[reply]

February 2[edit]

Pills as seeds[edit]

Is it possible to bury some kind of a pill or other medicine in the ground and for it to grow into something? — Preceding unsigned comment added by 2001:999:400:51B0:41D3:1290:1AEA:9E2F (talk) 06:25, 2 February 2023 (UTC)Reply[reply]

Not unless it's an actual seed. ←Baseball Bugs What's up, Doc? carrots→ 08:13, 2 February 2023 (UTC)Reply[reply]
There are "pelleted seeds" that resemble pills, and there are encapsulated seeds that are coated with fertilizer that also resemble pills. Just plant them, water them. and watch them grow. 136.56.52.157 (talk) 20:27, 2 February 2023 (UTC)Reply[reply]
Those are actual seeds. If the OP plants a medicine pill to watch it grow, why stop there? The OP could plant money and see if it produces a tree that money grows on. ←Baseball Bugs What's up, Doc? carrots→ 21:40, 2 February 2023 (UTC)Reply[reply]
I once spread bird seed all over my yard; sure enough, soon there were birds on my lawn! 136.56.52.157 (talk) 05:03, 3 February 2023 (UTC)Reply[reply]
Feathers stuck in the ground sometimes grow into roosters Down Here -- Jack of Oz [pleasantries] 19:18, 3 February 2023 (UTC) Reply[reply]
See also:
136.56.52.157 (talk) 20:32, 2 February 2023 (UTC)Reply[reply]

By the way...[edit]

...There could be a WP article on Synthetic seeds:

--136.56.52.157 (talk) 05:41, 3 February 2023 (UTC)Reply[reply]

Here I find: "when it comes to comparing them to your average supernova, [kilonovae] fall far short, whether it be in terms of luminosity or power". But here it says: "A kilonova is an even stronger type of explosion than the typical supernova that happens when large stars blow up." Which is correct? The Wikipedia articles on these events do not contain data that allow for a comparison. When comparing events, one should also distinguish between the maximal power (energy output per time unit) during an event and the total energy over the lifetime of an event.  --Lambiam 12:11, 2 February 2023 (UTC)Reply[reply]

The sources in the Wikipedia article kilonova agree with your first source, and not the second. I'd ignore the second. --Jayron32 12:47, 2 February 2023 (UTC)Reply[reply]
I believe the issue is the word "stronger." Neither is demonstrating physical strength. So, that word is not being used properly. What should be explained is relative brightness. The article on Wikipedia explains that the average brightness of a kilonova is much less than a supernova, but the peak brightness is far greater. 97.82.165.112 (talk) 19:51, 2 February 2023 (UTC)Reply[reply]
Kilonova emits only relatively weak electromagnetic radiation. However the total energy of the explosion is still enormous although it is mainly emitted in the form gravitational waves or neutrinos. Ruslik_Zero 20:37, 2 February 2023 (UTC)Reply[reply]


February 3[edit]

End of the sun[edit]

Please read the whole section of this page:

https://www.knowledgepeoplecreators.com/2021/03/what-are-zodiac-signs-will-sun-ever.html

...that is titled "Will the sun ever stop shining??" (That is, keep reading until you reach the next section, which is about the moon shining.) Do some scientists disagree with some parts of this?? Georgia guy (talk) 00:34, 3 February 2023 (UTC)Reply[reply]

It seems reasonably accurate for a very brief summary. See Formation_and_evolution_of_the_Solar_System#The_Sun_and_planetary_environments for a more detailed description. I don't think there's much scientific debate about the future evolution of the Sun in broad strokes, although there may be some disagreement about the details. For instance, it's not clear if the expanding Sun will envelop the Earth like it will swallow Mercury and Venus, since Earth's orbit is just on the boundary of where it might be enveloped. Of course, for some definition of "scientist" and some definition of "disagree", there are surely some "scientists" who "disagree" with "some parts of this". Is there a particular point that you have a question about? CodeTalker (talk) 02:20, 3 February 2023 (UTC)Reply[reply]
They have some stuff backwards. So, to calibrate your thinking here, it's important to understand that stars get brighter with age on the main sequence. The reason is, as they fuse hydrogen in the core into helium, the core becomes denser. The core pressure thus goes up, and this is what determines the rate of fusion in the core, so the rate of fusion goes up, producing more light—a positive feedback loop, just a really slow one, to human time scales, since stars are really big. When the Sun formed it was only about 60% as bright as today: see faint young Sun paradox.
When a planet is "too close" to its star, it gets enough light that it's too hot for liquid water to exist, and if there's a lot of water, a runaway greenhouse effect happens as the water evaporates into the atmosphere. Water vapor is a really potent greenhouse gas. Then, gradually, the H2O gets photodissociated by ultraviolet light from the star into H and O, and the hydrogen can then escape into space, as terrestrial planets are too light for their gravity to hold on to the lightest element. This is why Earth doesn't have a bunch of hydrogen or helium floating around. The thinking among scientists has come around to believing this is likely the exact process that happened on Venus billions of years ago. Venus is almost exactly the mass of Earth, Earth's "twin", and likely looked very similar when the Solar System formed. But, it was "too close" to the Sun, outside the circumstellar habitable zone (CHZ), and thus the Sun fried it and drove off all its water.
Then if you put two and two together: the CHZ moves outward as a star ages, because it gets brighter. So, the Sun's CHZ has slowly been moving outward, and estimates are in around 600,000,000 years it will start moving outside of Earth's orbit, and the same processes that likely happened to Venus will repeat on Earth. The Sun still has 5 billion years left on the main sequence, which gives plenty of time for it to drive off all of Earth's water and leave it a dessicated husk like Venus.
Helium flash.svg
Stellar evolution: Then, yes, the Sun will finish its life on the main sequence and enter the red giant phase. There is no real debate here since the physics are quite well-understood. Eventually the core has used up enough hydrogen "fuel" that it stops producing enough energy to "inflate" the star's upper layers against gravity, which keeps trying to collapse the star. Gravitational collapse ensues until a "shell" around the core becomes hot enough to start fusing hydrogen. This halts the collapse, and in fact then starts to inflate the star hugely. The reason is the square–cube law: the shell surrounds the core, so by definition it has a larger volume. Any shape's volume grows more quickly than its surface area does—the volume goes up with the cube of size, while surface area only goes up with the square. This is why elephants can't jump like rabbits among other things. In our star, the photon flux through any given "slice" of the star is now much higher, and so the outer layers of the star heat up and expand from all that energy. Then as more "fuel" gets used up, the helium core ignites, followed by fusion in upper layers, which gradually "blows off" the outer layers from the extreme stellar wind produced (again, because of that square–cube law) and what's left is a white dwarf. --47.147.118.55 (talk) 10:23, 3 February 2023 (UTC)Reply[reply]
  • If by "some" you mean "more than one" and if by "scientists" you mean "a person who does science", then I have no doubt you could find at least 2 scientists who disagree with 2 parts of that article, so the answer to your question should be an unambiguous yes. Undoubtedly some scientists disagree with some parts of that article. --Jayron32 11:48, 3 February 2023 (UTC)Reply[reply]

I was at a lecture on the history and future of the sun, some years ago. Afterward, a lady asked with alarm if it was really true that in a few million years the sun would swell up and kill the earth. The presenter said no, billions, not millions. The lady breathed a sigh of relief -- as if that difference mattered to her, or to humanity. Dicklyon (talk) 12:09, 5 February 2023 (UTC)Reply[reply]

That's an old... I say, that's an old joke, son. :) ←Baseball Bugs What's up, Doc? carrots→ 13:15, 5 February 2023 (UTC)Reply[reply]

Kidney theft in real life?[edit]

I just watched the wonderfully silly Jean-Claude Van Damme movie, Pound of Flesh - which has the premise of "they stole JCVD's kidney - and now he's going to kill all the bad guys to get it back!".

Features the old "guy wakes up in a bath of ice after being drugged, to find his kidney removed" story. I used to think it was just a urban legend - but hasn't this actually really happened a few times now, with organ trafficking gangs? Anyone know of any actual specific examples? Iloveparrots (talk) 17:15, 3 February 2023 (UTC)Reply[reply]

Wikipedia has an article titled Organ theft. The classic story of someone waking up in a bathtub of ice and a note on their chest, having had their kidneys removed, is not a thing that has ever happened, but there are documented cases of shady organ trafficking schemes, but these usually fall under the realm of coercing people who are either prisoners, or poor, into giving away their organs against their own interests. --Jayron32 17:20, 3 February 2023 (UTC)Reply[reply]
Forgive this psuedo-WP:NOTAFORUM divergence, as this is definitely not what the OP was inquiring about, but in the context of Jayron's response, this recent development felt rather apropos. SnowRise let's rap 05:42, 4 February 2023 (UTC)Reply[reply]
Snopes says it's a myth. Clarityfiend (talk) 23:12, 3 February 2023 (UTC)Reply[reply]

Ehlers-Danlos and beeing fast[edit]

It's true, that Humans with Ehlers–Danlos syndromes have usually a talent with running and speeding running. 2A02:908:424:9D60:C51C:BD84:3557:7240 (talk) 23:37, 3 February 2023 (UTC)Reply[reply]

See Wikipedia:Verifiability, not truth. Do you have a question? Shantavira|feed me 09:15, 4 February 2023 (UTC)Reply[reply]
The notion of "having a talent" is hard to define. If they have this talent, they should be advised that at least some physical therapists think that patients with EDS should be encouraged to avoid high-impact activities, including running.[2]  --Lambiam 22:00, 4 February 2023 (UTC)Reply[reply]

February 4[edit]

Global warming causing cold wave[edit]

I have seen that some areas are facing record cold wave, and most places also face record heat wave during summer. Antarctica glaciers are melting, some areas don't have snowfall like 1960s. Then how global warming is causing extreme cold in some areas?

I understand how rising temperatures can increase cloud burst, cyclones, tornadoes, storms, floods, but this cold wave due to global warming is confusing. PringalDer (talk) 06:28, 4 February 2023 (UTC)Reply[reply]

Changing wind patterns. In general, it gets warmer, but there are a few areas where in winter winds from high latitudes get more common. For example, in some central and eastern parts of North America, winds from the Arctic get more common in winter, leading to extreme cold outbreaks. These winds change because of regional changes in air pressure, which in turn result from changes in temperature at high latitudes. PiusImpavidus (talk) 11:00, 4 February 2023 (UTC)Reply[reply]
See this BBC article: "Climate change: Arctic warming linked to colder winters", and this Science article: "Linking Arctic variability and change with extreme winter weather in the United States".  --Lambiam 11:38, 4 February 2023 (UTC)Reply[reply]
The article Effects of climate change#Heat waves and temperature extremes has some more references. Mike Turnbull (talk) 12:05, 4 February 2023 (UTC)Reply[reply]
A lot of it is due to the Jet stream wiggling more violently so it goes up and down more. See yhe first picture in that article for how it goes up and down. When it comes down the area behind can get very cold. NadVolum (talk) 16:04, 4 February 2023 (UTC)Reply[reply]
Global warming cooling was a recognised descriptive issue ages ago,that's why we now call it climate change, and there are a group of people whose intent is to attribute every bit of weather to it. https://climateattribution.org/ Greglocock (talk) 21:37, 4 February 2023 (UTC)Reply[reply]
You do realize that a change to the climate would necessarily mean impacts on the majority of weather events, you know, since the climate is made of the collection of individual weather events taken together as trends. In fact, the surprising thing would be if we could only attribute a small minority of extreme cases to climate change, since they would, by definition, be outliers and not constitute the trend. A far smaller group of people don't seem to understand this, and expect the opposite (or likely just are trying to find other ways to basically deny anthropogenic impacts upon, and changing, climate exists). --OuroborosCobra (talk) 22:53, 4 February 2023 (UTC)Reply[reply]

Voltage multiplier for rectified flyback transformer?[edit]

I have a flyback transformer with built-in diode. Since the output is pulsed, I thought I could use a voltage multiplier to increase the voltage. However, after looking at the Villard or Cockcroft–Walton circuit, I doubt it can work, since the rectifier diode will make the source an open circuit when the voltage drops. Am I right in thinking that multiplying the voltage (using only capacitors and diodes) is simply impossible? Prevalence 22:55, 4 February 2023 (UTC)Reply[reply]

From Flyback transformer: "The pulse train coming from the flyback transformer windings is converted to direct current by a simple half wave rectifier. There is no point in using a full wave design as there are no corresponding pulses of opposite polarity. One turn of a winding often produces pulses of several volts. In older television designs, the transformer produced the required high voltage for the CRT accelerating voltage directly with the output rectified by a simple rectifier. In more modern designs, the rectifier is replaced by a voltage multiplier." So it is both possible and routine. Philvoids (talk) 00:51, 5 February 2023 (UTC)Reply[reply]
For the flyback they used a flyback transformer though as it could produce the big current with the nice sawtooth shape needed for the coils in an old TV. Is this to drive an old CRT? NadVolum (talk) 01:03, 5 February 2023 (UTC)Reply[reply]
The flyback comes from an old CRT tv. I want to use it to generate high voltage for some experiments, preferably 50kV or more. Prevalence 02:20, 5 February 2023 (UTC)Reply[reply]
I know the diode can be replaced by a multiplier. But I can't remove the diode, since it is inside the housing, and the whole thing is potted. The question is, is it possible to add a multiplier after the diode. Prevalence 01:46, 5 February 2023 (UTC)Reply[reply]
I think the diode forms the first stage of the voltage multiplier. The usual anode voltage for 20 to 26 inch colour CRT's was 25kV and I would never come near that potential except with a special long-reach high voltage probe. Please tell someone what your "experiments" will be. Philvoids (talk) 18:16, 5 February 2023 (UTC)Reply[reply]
If you want to produce really high voltages you're better off with the diodes and capacitors. The transformer might break down with flashing between coils. Also I think you're less likely to klll yourself with the voltage multiplier. NadVolum (talk) 11:13, 5 February 2023 (UTC)Reply[reply]

February 5[edit]