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December 21

"Venusiforming" Venusforming Veneriforming the Earth

First, apologies for the bad Latin in the question (I'd appreciate knowing what the word should be, although I guess that's more a matter for the language desk). More seriously, I notice that different points of view are listed in Runaway greenhouse effect#Earth on whether it's theoretically possible to turn Earth today into a facsimile of Venus: what's the latest opinion on whether it's possible for us to release enough CO₂ to do so at current technology levels? And if not, could it be done by maxing out industrial production of much more potent greenhouse gases like CF₄ or SF₆? (Asking purely out of curiosity, and certainly not for any Venusian friends.) Double sharp (talk) 08:26, 21 December 2022 (UTC)[reply]

Cytherean actually talks about this, theoretically, it would be Cytheriforming but almost no one would know the term, so I'd stay with Venusiforming.Naraht (talk) 09:01, 21 December 2022 (UTC)[reply]

Why the i? Assuming that terra in terraforming is nominative (but is it?), then venusforming would do nicely. Something like veneriforming (i from dative case, but then it would have to be terraeforming, I guess) would also sound good. --Wrongfilter (talk) 09:25, 21 December 2022 (UTC)[reply]

Great, "Venusforming" it is then! :) Double sharp (talk) 12:29, 21 December 2022 (UTC)[reply]

These constructions are usually formed from the accusative (example "Jovian" from the accusative Jovem, not the nominative Iuppiter: the final -m tends to disappear in Romance languages). So if you were going to do it that way "venereform" would be more logical. 2A00:23C4:570A:601:E1F1:B501:4B61:3168 (talk) 12:57, 21 December 2022 (UTC)[reply]

In forming such Greek or Latin-based scientific composite terms, usually the first part is based on the stem of the component. The stem of Terra is Terra- and that of Venus is Veneri-. For other planets, the stem of Mercurius is Mercuri-, that of Mars is Marti-, and that of Jupiter is Jovi-. --Lambiam 16:54, 21 December 2022 (UTC)[reply]

OK. I hope I don't have to change the title a third time! :) Double sharp (talk) 16:58, 21 December 2022 (UTC)[reply]

While the direct effect of "us" releasing CO₂ in the atmosphere is (per John Houghton) unlikely to create conditions resembling Venus, there are indirect effects for which we have no good models backed by scientific consensus to base worst-case assessments on. The indirect effect of permafrost thawing, which may engender positive feedback, may more than double the greenhouse gases in the atmosphere, not only for CO₂ but even more so for methane, a more potent greenhouse gas. --Lambiam 16:41, 21 December 2022 (UTC)[reply]

The article says that 2013 calculations suggest you'd need ten times as much CO₂ as the direct effect would give you to cause a runaway greenhouse: would there be enough methane released to compensate, as a rough order-of-magnitude estimate? And what if we started emitting tetrafluoromethane as well, seeing as it's about four orders of magnitude better as a greenhouse gas – would we be able to make enough? Double sharp (talk) 16:47, 21 December 2022 (UTC)[reply]

One difference is that Venus has a very weak magnetosphere, and so the solar winds break apart water in the atmosphere, and strip it away. Card Zero (talk) 16:51, 21 December 2022 (UTC)[reply]

Well, I didn't intend to ask about turning off Earth's magnetic field – just about creating a runaway greenhouse, since that's probably the most well-known feature of Venus. :) Since we can retain water vapour in our atmosphere, and that's also a greenhouse gas, that should make this task easier. Double sharp (talk) 16:54, 21 December 2022 (UTC)[reply]

This is a side-track, but there are albedo, the hydrological cycle and global dimming to consider. I mean, water vapor forms clouds which tend to reflect radiation into space, and then the amount that the atmosphere can hold is limited since it returns the ground as rain, so its function as a greenhouse gas is qualified by these effects. Card Zero (talk) 17:42, 21 December 2022 (UTC)[reply]

There are also other effects. Above a certain rise in temperature, there will not only be a massive die-off of the fauna, but also of the flora. The decomposing biomass will release huge amounts of CO₂.^[1] --Lambiam 17:16, 21 December 2022 (UTC)[reply]

@Lambiam: That's not quite right. In the first declension the accusative ends in -am, in the second in -um, and in the third in -em. Both Mercury and Mars are second declension - Venus is third, which is how we get the word venereal. The stem of Jupiter is not jovi-, it's jove-, which is why the poetic name of the planet is Jove. The adjective "jovial" comes from the adjectival form jovialis. The nominative of Mars is Martius and it declines similarly to Mercurius, Saturnus and Neptunius, giving us martial, mercurial, saturnine and Neptunian. They are not comparable - you cannot argue the form ~~Veneriform~~ from them. The stem is Vener-, to which the case endings are added. 2A00:23C4:570A:601:9065:CFB9:73C7:6751 (talk) 20:07, 21 December 2022 (UTC)[reply]

That is not quite right. I indeed simplified a bit by declaring Veneri- to be the stem, but in general an epenthetic -i- is inserted when a third-declension consonant stem would otherwise be followed by a consonant, as in flor- (the stem of flos) + -genus = florigenus, and in leg- (the stem of lex) + -fer = legifer; compare also the adjective veneriform, meaning "having the form of a Venus clam". This is not a golden rule, though; the Latin stem of Iuppiter is actually the consonant stem Iov-; hence Iuppiter < Iov- + pater, and not *Iovipiter. But in later coinage, we see the -i- inserted, as in jovicentric. Furthermore, the nominative of the Latin proper noun Mars for both the god and the planet is Mars. The Latin proper noun Martius refers to the month of March. --Lambiam 11:04, 22 December 2022 (UTC)[reply]

Mars, Martis is third declension (consonant stem; the third declension also includes i-stems, such as adjectives in –alis). —Tamfang (talk) 20:14, 24 December 2022 (UTC)[reply]

There's enough carbon around to get us to 7000 ppm, which sounds like a bignum, but for 10s of millions of years mammals coped with (or more exactly, thrived in) 2000 ppm, and 7000 is only two doublings of that. However i see some idiot is proposing turning water vapor (aka clouds) over the oceans into drinking water. This will lower earth's albedo and so increase the amount of downwelling heat flux. Greglocock (talk) 20:46, 21 December 2022 (UTC)[reply]

OK, all this seems to mean that we probably couldn't do it just with CO₂, but secondary effects might push it over. A Scientific American article suggests we need 30,000 ppm CO₂ to do that.

So, what about my follow-up – could we seal our own runaway-greenhouse doom by trying to lock carbon up as CF₄? Presumably we'd need three to four orders of magnitude less per its greenhouse warming potential, but could we engage in fluorocarbon production at that scale? Double sharp (talk) 03:25, 22 December 2022 (UTC)[reply]

OK, tetrafluoromethane can be made by directly fluorinating carbon according to Ullmann's encyclopedia. Our Fluorine article says that "At least 17,000 metric tons of fluorine are produced each year"; even assuming we react all that with carbon, and making just the order-of-magnitude assumption that one ton of CF₄ is about as bad as 10,000 tons of CO₂, this does not appear to be enough by several orders of magnitude (still). I am not sure if the 17,000 tons figure refers only to elemental fluorine, though. (Well, terraforming is a massive endeavour anyway, so it stands to reason that the same is true of Veneriforming!)

(The idea behind the question was proposals to use perfluorinated gases to terraform Mars.) Double sharp (talk) 12:04, 22 December 2022 (UTC)[reply]

5.6 million tonnes of fluorite ore were extracted in 1989, which was apparently the peak. Converting 100% of it to CF₄ (assuming fluorine is the limiting reagent), this still seems to be about three orders of magnitude too little. (It results in 3.15E9 kg of CF₄; the atmosphere has mass 5.15E18 kg, and 1 ppm CF₄ should be in the right order-of-magnitude ballpark to think about doing this – 3% CO₂ would do it, and CF₄ is about four orders of magnitude more potent.) Admittedly this is only one year's worth of ore, so dumping CF₄ into the atmosphere for about a millennium should do the trick. Double sharp (talk) 13:19, 22 December 2022 (UTC)[reply]

Estimate a lower bound by finding the amount of gold that's been harvested (some over 5,000 years ago but mostly in the last century or so), dividing by (all-time harvest plus the amount of gold in the crust), then multiplying that by the amount of fluorine in the crust? Sagittarian Milky Way (talk) 05:09, 23 December 2022 (UTC)[reply]

Estimates on the amount of gold that's ever been harvested are mostly around 200,000 tonnes = 2E8 kg. According to Abundance of elements in Earth's crust (which lists abundances by mass fraction), the continental crust (whose mass is about 2E22 kg) is 4 ppb gold (which amounts to 8E13 kg). So we have extracted about 2.5E−6 of what we theoretically could.

As for fluorine, the crust is 585 ppm fluorine by mass (obviously in compounds), which amounts to about 1E19 kg. This could get us 2E19 kg of tetrafluoromethane, which is actually more than the atmosphere of Earth. If we extract about 2.5E−6 of that, we would release 5E13 kg of tetrafluoromethane, which should be enough (based on previous posts) to create a runaway greenhouse effect.

Or we could more sensibly dump all that tetrafluoromethane on Mars. Double sharp (talk) 09:26, 23 December 2022 (UTC)[reply]

Effects of a Mutation to reactivate L-gulonolactone oxidase? (Vitamin C producer)

L-gulonolactone oxidase is the last step in the Enzymatic sequence which produces Vitamin C in the large majority of Mammal Species. It has been lost in humans (and the rest of the dry nosed apes), some bats etc. If a person was born in the last 20 years where that gene had mutated *back* to properly generate the enzyme (the mutation back and forth has apparently occurred in the history of some bird species) would it be obvious to the person, their family, medical professionals? I *guess* it would be obvious in the event that if everyone in down was coming down with scurvy and this person didn't, but otherwise? Naraht (talk) 17:27, 21 December 2022 (UTC)[reply]

I do not think that any simple mutation can reactivate this (pseudo)gene as it has decayed significantly. Ruslik_Zero 19:39, 21 December 2022 (UTC)[reply]

I would think that as well, but given that there have been loss and regain in bird evolution, I'd like to get a feeling for how "decay" is measured. Do we know that there would be a stretch of (say) 18 amino acids that would need to be in a specific order (and thus 54 ACGT) and we know that of the 54 have two missing and one changed?Naraht (talk) 15:30, 22 December 2022 (UTC)[reply]

What would be the point? It would die out again. Um..., unless people altogether give up on eating greens and fruit. Is our motto to be - the future is not green, the future is junk food :-) NadVolum (talk) 12:52, 23 December 2022 (UTC)[reply]

Not asking what the point would be, humans iun the 20th century are in situations where it generally isn't *needed*, I'm asking what the medical effects would be for such an individual (including detectablitiy).Naraht (talk) 04:24, 24 December 2022 (UTC)[reply]

If it was produced in reasonable amounts I doubt it would be noticed. None of the chemicals involved has bad effects. If too much then they'd suffer from the usual effects of too much vitamin C but that's quite a lot, only real fans of Pauling do that but I suppose it would be possible if we suddenly got the ability to produce it. There may be a good reason why producing it has a cost that is worth avoiding and the usual explanation that it was lost because it was not necessary due to its abundance is only part of the story. NadVolum (talk) 10:34, 24 December 2022 (UTC)[reply]

Reading Vitamin C megadosage, wasn't Pauling's idea based on the inactivation of GULO being an error, and thus advocating taking as much vitamin C as would be made if the enzyme were active? If so, then the results should be similar to those of taking vitamin C megadoses.

The idea is quite fun to fantasise about in the Age of Sail context, though. Double sharp (talk) 16:59, 24 December 2022 (UTC)[reply]

December 23

Will we ever see Ceratopsids duke it out with abelisaurs or megaraptorans?

I am so desperate for Labocania to be an abelisaur or a megaraptoran so that we can finally have an abelisaur or megaraptoran that coexisted with ceratopsids and engage in epic fights for survival, I just need my megaraptoran vs ceratopsid fight to be a reality so badly. CuddleKing1993 (talk) 05:41, 23 December 2022 (UTC)[reply]

If we do ever manage to resurrect dinosaurs, I'd guess that the process will probably be so difficult and expensive that it would be unlikely that they would be placed in interspecies kumite - even not withstanding animal cruelty laws. Not when they can be stuck in a zoo somewhere and an entrance fee charged for visitors to see the animal over its lifetime. --Iloveparrots (talk) 06:32, 23 December 2022 (UTC)[reply]

Such speculative "desperate" discussions have no place on conversations to build a high quality encyclopedia. CuddleKing1993, are you here to build an encyclopedia, or to spout garbage? If the second, then please go blog elsewhere. Cullen328 (talk) 06:47, 23 December 2022 (UTC)[reply]

We have learned from the film series that they are bound to escape from their enclosures. Will they turn on each other, though, or form an alliance against their captors? --Lambiam 07:01, 23 December 2022 (UTC)[reply]

Works of fiction cannot bring anything of value to encyclopedic coverage of the actual species, except possibly for an "in popular culture" section, which must be rigorously referenced. In my opinion, every such entry everywhere should be deleted on sight, unless correctly referenced. Cullen328 (talk) 07:13, 23 December 2022 (UTC)[reply]

Who knows what will happen in the far future but I'm pretty certain we'll be long dead before anything like that happens. I think you're better off trying virtual reality for your wish fulfillment. NadVolum (talk) 12:45, 23 December 2022 (UTC)[reply]

@CuddleKing1993: I agree, such a fight would be epic. I would encourage you to continue researching and get back to us with your findings, update the respective articles, etc. Dinglepincter (talk) 23:32, 25 December 2022 (UTC)[reply]

December 26

Everlasting lightbulb

Is it true that it would be possible to create a lightbulb that never burned out? But that Big Lighting don't do this because it's in their financial interest for people to keep buying replacement bulbs. — Preceding unsigned comment added by 146.200.126.234 (talk) 02:59, 26 December 2022 (UTC)[reply]

Never? It wouldn't be possible to create anything material that would outlive the heat death of the universe. 42.189.193.127 (talk) 03:07, 26 December 2022 (UTC)[reply]

In a case of "they don't make 'em like that anymore", there is the Centennial Light in Livermore, CA. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:34, 26 December 2022 (UTC)[reply]

We could still have those if brightness inflation didn't happen. At first you could buy extremely low temperature ("warm" color) incandescents that were only a few watts and about as bright as a candle but brightness inflation happened and we get wasteful 100 watt "cool" white incandescents that are about 150 to 130 candles depending on clear or frosted. I unscrewed all but a single clear 15 to 25 watt incandescent in a cheap chandelier and put the dimmer switch way down and could still read and avoid a minefield of Legos at ridiculously low brightnesses (the light was way warmer than without dimming). An incandescent can be easily designed to last over a century if it's dim enough although max duration might need very few turn offs per century (including blackouts and uscrewings). But at least now we have rapidly cheapening 50,000 hour LED bulbs with way more and rapidly increasing light per watt than incandescents. Which is already leading to 300 watt equivalent LEDs as soon as efficiency raises the "brightest LED we can make that lasts a sane time" to that. People are never satisf

ied. Sagittarian Milky Way (talk) 18:03, 26 December 2022 (UTC)[reply]

"might need very few turn offs per century " : maybe this is the most important point. Turning on/off and cooling down/heating up places a strain on it much higher than simply emitting light. Bumptump (talk) 11:56, 29 December 2022 (UTC)[reply]

I'm not sure about never, but you used to be able to buy "long-life" filament bulbs that simply had a thicker filament so they were not very bright. But there is some truth in the idea of their planned obsolescence. See Phoebus cartel. Shantavira|^{feed me} 09:20, 26 December 2022 (UTC)[reply]

some good advice here: [2] Dr Dima (talk) 00:25, 28 December 2022 (UTC)[reply]

December 27

Late Cretaceous American Interchange: Where is the Smoking Gun?

How is there any proof that there was an actual american biotic interchange between South American fauna and North American fauna during the late Cretaceous? keep in mind that the american biotic interchange that started during the Piacenzian had terror birds, glyptodonts, megalonychid ground sloths, megatheriid ground sloths, nothrotheriid ground sloths, toxodontids, new world porcupines cross over from South America into North America while gomphotheres, dire wolves, sabertooth cats, spectacled bears, jaguars, cougars, camelids, white-tailed deer, marsh deer crossed over from North America into South America, so if there was an actual american biotic interchange during the late Cretaceous, why is there no evidence of animals like abelisaurs, megaraptorans, noasaurids, elasmarians, notosuchians, unenlagiinae unenlagiids crossing over from South America into North America and animals like lambeosaurine hadrosaurs, edmontosaurini hadrosaurs, chasmosaurine ceratopsids, centrosaurine ceratopsids, tyrannosaurids, eudromaeosaurs crossing over from North America into South America? CuddleKing1993 (talk) 09:09, 27 December 2022 (UTC)[reply]

The animals that you list as crossing between North and South America all lived many millions of years after the end of the Cretaceous. CodeTalker (talk) 03:52, 28 December 2022 (UTC)[reply]

The OP wrote that these animals crossed during the Piacenzian (in the Great American Biotic Interchange, using the Panamanian land bridge that formed during that age). The question – as I interpret it – is, why didn't a similar exchange take place during the late Cretaceous? The tragic fact of the matter is, as was pointed out to the OP before, in the late Cretaceous, North America was not connected to South America. --Lambiam 07:57, 28 December 2022 (UTC)[reply]

So why did apparently kritosaurini hadrosaurs and nodosaurs cross over into South America? CuddleKing1993 (talk) 11:16, 28 December 2022 (UTC)[reply]

To repeat myself from 11 days ago in response to an earlier question "according to this paper there was probably a link between North and South America during the Campanian (Late?), via a line of volcanic islands, allowing "a dispersal route for hadrosaurids and other vertebrates"." Mikenorton (talk) 14:18, 28 December 2022 (UTC)[reply]

Then why did only kritosaurini hadrosaurs and nodosaurs disperse into South America? CuddleKing1993 (talk) 20:30, 28 December 2022 (UTC)[reply]

Maybe some of them couldn't swim? Maybe all of them could swim, but the inter-island seas were hazardous and only the two you mention were lucky enough to make it all the way? Maybe some that made it part of the way were then wiped out by volcanic eruptions? If you haven't found the answer in peer-reviewed literature, then almost certainly no-one knows. Maybe future discoveries will allow someone to figure it out, in a century or two from now. Maybe we'll never know: Paleontology is like that. {The poster formerly known as 87.81.230.195} 51.194.245.235 (talk) 12:34, 29 December 2022 (UTC)[reply]

December 28

IQ and Sex

Are there any scientific studies on the difference in intelligence between the sexes? In particular, I am interested in whether it is true that boys are slower to mature intellectually. Are there studies? 2A02:908:424:9D60:0:0:0:8846 (talk) 23:10, 28 December 2022 (UTC)[reply]

This very much depends on one's definition of intelligence. Shantavira|^{feed me} 09:14, 29 December 2022 (UTC)[reply]

There are, cat , pigeons. https://www.nature.com/articles/nature04966 Greglocock (talk) 01:25, 29 December 2022 (UTC)[reply]

Sex differences in intelligence would be a good place to start. Clarityfiend (talk) 06:14, 29 December 2022 (UTC)[reply]

It seems very strange for Nature to have a paper about sex differences in IQ when IQs are set up balancing up any differences so overall there is no difference. Intelligenceis a better name for what you're looking for but it is multi faceted. NadVolum (talk) 19:30, 29 December 2022 (UTC)[reply]

IQ tests are calibrated for a given population so that the distribution of test scores closely approximates a normal distribution whose mean equals 100 and whose standard deviation equals 15. Therefore it is meaningless to compare scores for population A obtained with a test for population A with scores for population B obtained with a test for population B. If there is a significant difference between the distributions, it signals a problem with the calibration. However, this does not mean that the distributions for two subpopulations of a given population are the same. If you compare the IQ scores of 25-year old college dropouts with those of 25-year olds who earned a PhD, it will be amazing if you don't find a difference. There is no a prori reason why there would not be sex-related differences in the distributions of height, or muscular strength, or hearing acuity, or pain endurance, or empathic ability, or remembering people's birthdays, or whatever. People should (IMO) get over with being so absurdly focused on IQ as if scoring 130 makes one more valuable then another human being who scores 70. The high scorer may be a total douchebag, while the other is a caring spouse and parent, bringing happiness to the lives of many. Also, inasmuch as intelligence has relevance for our daily life, it is really multifaceted, in a way a single score cannot capture. --Lambiam 20:02, 29 December 2022 (UTC)[reply]

Crack Theory: Kritosaurini were NOT hadrosaurs?

What if Kritosaurini were actually lineage of iguanodonts that resembled true hadrosaurs through convergent evolution with a ghost lineage from the late Jurassic or early Cretaceous that were widespread across the globe? CuddleKing1993 (talk) 23:51, 28 December 2022 (UTC)[reply]

What if dolphins were actually ichthyosaurs? Do you have an actual question? --OuroborosCobra (talk) 01:31, 29 December 2022 (UTC)[reply]

My question was trying to understand why kritosaurini iguanodonts were found in South America. CuddleKing1993 (talk) 01:58, 29 December 2022 (UTC)[reply]

@CuddleKing1993:, just a note; talk pages are not a general forum. --Magnatyrannus (talk | contribs) 02:46, 29 December 2022 (UTC)[reply]

December 29

What will the Andromeda–Milky Way collision look like?

Assuming the Andromeda–Milky Way collision is really going to happen, if there would be anyone on Earth left to see it, what would it look like? Would it look like a great lot of stars getting brighter and brighter, then getting dimmer and dimmer again? JIP | Talk 19:56, 29 December 2022 (UTC)[reply]

Stars will remain the roughly same but their configuration will change, with the Milky Way band gradually disappearing. Ruslik_Zero 20:08, 29 December 2022 (UTC)[reply]

The Hubble Space Telescope captured this image of two colliding galaxies. Located 300 million light-years away in the constellation Coma Berenices, the view has been nicknamed “The Mice” because of the long tails of stars and gas emanating from each galaxy. Otherwise known as NGC 4676, the pair will eventually merge into a single giant galaxy. Philvoids (talk) 20:31, 29 December 2022 (UTC)[reply]

Human extraterrestrial life?

Here's a question for you: could humans adapt to life on Mars, Europa, Enceladus, or Titan? 67.215.28.226 (talk) 20:48, 29 December 2022 (UTC)[reply]

Have humans adapted to life in the far north, does an Inuit with a nice fur coat count as adaptedas far as you are concerned? NadVolum (talk) 22:13, 29 December 2022 (UTC)@[reply]

No. I am asking without a spacesuit? 67.215.28.226 (talk) 22:18, 29 December 2022 (UTC)[reply]