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May 3

Hum in headphone amplifier

I have a headphone amplifier that has some hum in it. If I put my hand on the metal case, the hum goes away - or at least so low that I can't hear it. Does it need to be grounded?

There is a post on the back for grounding it, but I don't know what to ground it to. Years ago I had my turntable grounded to a water pipe, when the pipes were metal. My current house has plastic pipes, so what can I ground it to? Run a wire to the actual ground? Bubba73 ^{You talkin' to me?} 04:03, 3 May 2023 (UTC)

It is most likely a ground loop problem. What are the headphones plugged into? USB? If it's USB, then the device itself needs to be grounded; if it uses a 2-prong adapter or something, then there's your problem. 136.56.52.157 (talk) 06:29, 3 May 2023 (UTC)

They are Audeze CRBN electrostatic headphones. Bubba73 ^{You talkin' to me?} 06:31, 3 May 2023 (UTC)

At that price point, you should contact customer service for tech support: [1]. 136.56.52.157 (talk) 06:40, 3 May 2023 (UTC)

P.s. this query from Audeze might be helpful, it suggests that it most likely relates to RFI. Not mentioned however, is that there are RFI filters for such problems. 136.56.52.157 (talk) 17:25, 3 May 2023 (UTC)

The hum goes away when I touch the metal case of the headphone amp, which is a Stax SRM-400S. Bubba73 ^{You talkin' to me?} 23:59, 3 May 2023 (UTC)

A couple a days ago I had this exact same issue with two guitar amps. Relocating the new amp from the campfire table to the bare ground stopped the 60HZ buzzing. Indoors, placing it on the floor reduced the hum only some, so I clamped a tape measure to it and wrapped that around a quart can of varnish I have. :-) Modocc (talk) 00:06, 4 May 2023 (UTC)

I'll try moving the cables and the amp around. Bubba73 ^{You talkin' to me?} 01:28, 4 May 2023 (UTC)

I think I'm going to try a ground-loop isolator, for the XLR inputs into the amp. Bubba73 ^{You talkin' to me?} 00:05, 4 May 2023 (UTC)

How did the ancients deal with mold and mildew in ancient aqueduct systems?

Modern drinking water systems rely on chlorine etc. to prevent mold from growing in water systems. Ancient aqueduct systems must have been exposed to the outside elements. Surely they would have accumulated mildew over time? Or did enough sunlight do the trick? Yanping Nora Soong (talk) 12:08, 3 May 2023 (UTC)

Does lead piping suffer from mildew? One just hopes it kills the bugs quicker than the humans! Martin of Sheffield (talk) 13:13, 3 May 2023 (UTC)

Pethaps continuously moving water is less prone to this (biologist required). A second hypothesis is that they didn't know or care about what was growing in their water supply. Dr John Snow was the first to realise that drinking water with sewage in it was a bad idea, and that wasn't until 1854. Alansplodge (talk) 13:56, 3 May 2023 (UTC)

Molds aren't the problem, bacteria are. And they aren't a problem within the system, but on either end. Abductive (reasoning) 15:36, 3 May 2023 (UTC)

Not an issue. As an example Plymouth's drinking water was supplied via leats which are large drainage channels that drain Dartmoor. They are effectively canalised streams. The water in them is entirely drinkable, if a bit tannic. Greglocock (talk) 20:38, 3 May 2023 (UTC)

One may discover, just upstream and out of site from where you quenched your thirst, a dead sheep in the leat. DuncanHill (talk) 20:47, 3 May 2023 (UTC)

Correct, which is why you walk downstream before drinking. Survival101. Greglocock (talk) 00:35, 4 May 2023 (UTC)

Images in Egyptian tombs from the 15th to 13th century BCE show various water treatment devices. An ancient Sanskrit text on medicine the Sushruta Samhita specified various methods such as boiling water under the sun and filtering it through sand and coarse gravel. Hippocrates c. 460 – c. 370 BC designed a crude water filter to “purify” the water he used for his patients. Later known as the “Hippocratic sleeve,” this filter was a cloth bag through which water could be poured after being boiled. Diophanes of Nicaea of the first century BC advised putting macerated laurel into rainwater, Paxamus proposed that bruised coral or pounded barley, in a bag, be immersed in bad tasting water and the eighth century Arabian alchemist, Gerber, described various stills for purifying water. Sir Francis Bacon in his compilation "A Natural History of Ten Centuries" 1627 discussed desalination and began the first scientific experimentation into water filtration. Philvoids (talk) 00:33, 4 May 2023 (UTC)

The best way to purify water is to warm it with some malt, boil it with some hops, let it cool and add the yeast. A few days later your water is fit for anyone! :-) More seriously, much weak ("small") beer was drunk prior to 20C just because it was safe, unlike the water supply from wells next to cess pits (see Alansplodge above. Martin of Sheffield (talk) 07:39, 4 May 2023 (UTC)

(Insert joke based on reading "20C" as a temperature in Celsius here.) --174.89.12.187 (talk) 18:17, 4 May 2023 (UTC)

(Point out that unlike 293K it would be 20°C.) Martin of Sheffield (talk) 19:38, 4 May 2023 (UTC)

20C??? That's a lot of electrical charge! 73.162.86.152 (talk) 06:42, 5 May 2023 (UTC)

Equivalent to downing 3-1/3 six-packs of Mountain Dew in a second. DMacks (talk) 06:51, 5 May 2023 (UTC)

The ancient Greeks and Romans added wine to drinking water, which killed some of the bacteria, according to this article. Adding wine also improved the taste of stagnant water, according to this website. Cullen328 (talk) 20:08, 6 May 2023 (UTC)

So I actually found the best answer to my question - ancient Romans used a piscina limaria, or settling basin, to settle and remove crud at the intake and just before a city. They were also used in baths. I'll add that to the Roman aqueduct article with good sources soon. There is probably much also unsaid about the use of UVC-rich sunlight. Mold, odor and discoloration is easy to see (probably why the miasma theory had currency before the germ theory). Yanping Nora Soong (talk) 08:48, 7 May 2023 (UTC)

May 4

Language and laugh

Why only humans have language?

And why humans laugh properly? Does humans have special ability in their tongue, throat, vocal cords?

Humans evolved in same environment with millions of species, so why can't animals have a language not just sounds. Some animals have bigger head than humans so their brain must have more capacity. If anyone checks brains of elephant, hippopotamus, great whale, what special thing is missing from their brain that human brains have? PatricSt (talk) 17:41, 4 May 2023 (UTC)

You could start by reading Origin of language. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:57, 4 May 2023 (UTC)

There is also an article titled Laughter which should answer many of your other questions. --Jayron32 18:06, 4 May 2023 (UTC)

"The prefrontal cortex is commonly associated with cognitive capacities related to human uniqueness: purposeful actions towards higher-level goals, complex social information processing, introspection, and language."^[2]  --Lambiam 20:12, 4 May 2023 (UTC)

See also Animal communication. Shantavira|^{feed me} 08:21, 5 May 2023 (UTC)

Rats also laugh, especially when tickled. However, they do so at frequencies higher than humans can hear, so this had gone unnoticed until quite recently. {The poster formerly known as 87.81.230.195} 90.213.18.208 (talk) 11:19, 7 May 2023 (UTC).

May 5

Coal merchant occupational diseases

I've just finished an article on coal merchants, once one of the most common businesses but now much rarer. The Dutch Wikipedia article on the topic is totally unsourced but mentions that back and shoulder injuries were common because of the backbreaking work of carrying heavy sacks. Does anyone know if there's a source on this to add? (Yes, I know about chimney sweeps' carcinoma, but I don't think it's directly relevant.) And of course any other sources to improve the article would be much appreciated. Blythwood (talk) 11:18, 5 May 2023 (UTC)

I don't have a reference but I would imagine hauling heavy sacks of anything could cause back and shoulder injuries and this is just stating the obvious. I doubt you need a reference for that. That said, black lung disease may be of interest. "It is common in coal miners and others who work with coal." (Referenced.) 41.23.55.195 (talk) 12:31, 5 May 2023 (UTC)

I know about Wikipedia:You do need to cite that the sky is blue but gimme a break here. 41.23.55.195 (talk) 12:43, 5 May 2023 (UTC)

This article may be of interest (not sure how RS but it has a named author). Alansplodge (talk) 12:55, 5 May 2023 (UTC)

Not related to your question, but some images of coal merchants here, here, here and here. Alansplodge (talk) 17:45, 5 May 2023 (UTC)

Thanks so much to both of you! Will add the photos and that source. Currently thinking about a DYK hook. Haven't found a specific source for black lung in people delivering coal but might try looking further. Blythwood (talk) 19:47, 5 May 2023 (UTC)

Pendulum Motion

Suppose a pendulum consists of a rigid slender rod. As the pendulum swings downward, the points closer to the free end of the rod are moving faster than the points closer to the fixed end, but all of the points are being accelerated by gravity at the same rate. I understand that gravity provides a torque about the fixed end, but somehow I can't intuitively understand what's allowing the points to have different speeds. Puzzledvegetable^{Is it teatime already?} 21:43, 5 May 2023 (UTC)

The gravity is applying a force to each part of the pendulum. But because it is rigid, there are forces withing the material called stress. This mostly counterbalances the force of gravity. It varies in strength and direction in different parts of the pendulum at different phases of the swing. Graeme Bartlett (talk) 21:50, 5 May 2023 (UTC)

Since the pendulum is a rigid body, gravity can be simplified to acting at the centre of mass. For a uniform rod this will be in the centre of the rod. Neglecting air resistance (probably not a valid assumption for a rod), then gravity acts on this centre and will vary from a maximum when the rod is horixontal to a minimum when it is vertical. Martin of Sheffield (talk) 22:12, 5 May 2023 (UTC)

The reason, though, this simplification can be made is due to forces acting within the rigid body, as indicated above by Graeme Bartlett. These internal forces counteract the effect of external forces (such as gravity) that threaten to shear it apart. If the stress (in the pendulum case more specifically the tension) exceeds a certain limit, it will still come apart.  --Lambiam 06:29, 6 May 2023 (UTC)

A related "real world" example of gravity acting on a rigid body anchored at one end is the popular "falling chimney" problem in intro-physics courses. Can't find a WP article about it. DMacks (talk) 23:31, 8 May 2023 (UTC)

If both are modelled as homogeneous straight rods of constant thickness, the equations for the pendulum and chimney are identical (until the chimney hits the ground). In practice, the chimney comes apart before it hits the ground, since the bound between the bricks cannot withstand the tension.  --Lambiam 21:01, 9 May 2023 (UTC)

May 6

Why is tungsten so cheap?

Why is tungsten so much cheaper than all the other noble metals like platinum and osmium? Or is it not that much cheaper and I'm just misunderstanding all the confusing price quotes that I find on the internet? They keep using different units for everything so I might just misunderstand them. – b_jonas 14:51, 6 May 2023 (UTC)

It may partially be that it's because it's not a Noble metal. --Phil Holmes (talk) 15:38, 6 May 2023 (UTC)

It also plays a role that tungsten is found in the relatively abundant minerals wolframite and scheelite, whereas platinum and osmium are both extremely rare.  --Lambiam 19:54, 6 May 2023 (UTC)

According to its article, the top three countries produce just under 90,000 tonnes of tungsten a year, for platinum it's under 150 (according to the graph in List of countries by platinum production; another source says a bit more, but still under 200 tonnes), for osmium various sources vary, but none of them are higher than 1 tonne. So tungsten is a lot more readily available. Clarityfiend (talk) 09:06, 7 May 2023 (UTC)

May 7

Domestic appliances

In ovens, washing machines, coffee machines etc. (at least those that I've needed to fix), it seems that the various heaters, motors and actuators have one terminal connected to the live rail, with the switches, thermostats and controllers on the neutral side. Why's it that way around? catslash (talk) 00:32, 7 May 2023 (UTC)

Live rail? Do these appliances run on tracks? Perhaps there is a rationale grounded in the theory of electricity, but I suspect this is an arbitrary convention, just like the colour codes of wires are an arbitrary convention.  --Lambiam 09:56, 7 May 2023 (UTC)

Lambiam: I assume the use by User:catslash of the expression “live rail” is just a local variation on what Wikipedia calls a busbar. Dolphin (t) 14:42, 8 May 2023 (UTC)

In electrical devices I've taken apart here in Canada, if the "hot" and "cold" wires could be distinguished then the switch was always on the hot side. Perhaps Mr. Catslash should identify what country the devices he or she is talking about are from. --174.89.12.187 (talk) 04:45, 8 May 2023 (UTC)

Indeed. I am not an electrical engineer (I can wire a plug and that's about it), but I'm fairly sure that in the UK this is a legal requirement under The Regulations. {The poster formerly known as 87.81.230.195} 90.213.18.208 (talk) 12:51, 8 May 2023 (UTC)

The regs apply to installations. The OP is asking about individual appliances which will be subject to some sort of type approval. Martin of Sheffield (talk) 14:21, 8 May 2023 (UTC)

Do they not also apply to appliances? I know that the Electricity at Work Regulations 1989 necessitate workplace portable appliances in the UK being regularly tested, and I'm also sure that imported appliances have to be manufactured to certain safety standards. What different standards are those? (The answer doesn't really matter to me, but might be relevant to the OP.) {The poster formerly known as 87.81.230.195} 90.213.18.208 (talk) 18:44, 8 May 2023 (UTC)

Yes, there are regulations for any appliances placed on sale in, or imported into, the UK. It's just that the wiring regs aren't the appropriate regulations. The old name (under the IEEE before BS took them over) was "Regulations for the Electrical Equipment of Buildings" and as the name suggests covered wiring (cable types, protection etc) protective devices (consumer units and the industrial equivalents) outlets, switches, grounding, equipotential bonding and half a dozen other things that I can't remember. They didn't cover equipment downstream of the socket outlet or equivalent switchgear. For instance the regs cover the installation of the cable up to a cooker switch, but not the internal wiring of said cooker. Likewise the regs cover ring mains but not the TV you plug in. Martin of Sheffield (talk) 22:13, 8 May 2023 (UTC)

The question concerns the inner workings of appliances in the UK, but typically manufactured in other European countries. It does not relate to the main on/off switch, if any, which would be on the "hot" side. catslash (talk) 22:16, 8 May 2023 (UTC)

cooker example catslash (talk) 23:02, 8 May 2023 (UTC)

Eagle's brow ridge

Eagle_eye#Eye_anatomy_and_physiology says the bony brow ridge "protects the eyes from protruding tree branches when it perches on trees, and also from prey which struggles to escape". Considering that some other birds of prey and generally many other animals live in a similar tree habitat and have similar hunting behavior, why that bony ridge evolved only in eagles? Apparently there are similar adaptations elsewhere that for some reason are not present among all genera living in the same habitat and sharing similar behavior. 212.180.235.46 (talk) 17:14, 7 May 2023 (UTC)

The process of genetic mutation is basically random, but mutations that happen to be beneficial tend to be selected for preservation in what is basically a process of optimization by trial and error. It is therefore entirely possible that one branch in the phylogenetic tree, by sheer luck, hits upon an improvement while nearby branches for which the same change would also be beneficial are less lucky. The counterpart of this is convergent evolution, in which somewhat distant branches occupying similar niches hit upon the same or similar improvements in the struggle for reproductive success.  --Lambiam 18:48, 7 May 2023 (UTC)

I don't think there is any reason to believe the sub-par sources that claim a protective function for the brow ridges. They could just as well be sexually selected, or to cut down on glare when hunting over water, or to keep water out of the eyes, or have no function at all. Abductive (reasoning) 07:18, 8 May 2023 (UTC)

May 9

Washington Metro

Would a lineside signal have prevented the June 2009 Washington Metro train collision? Or would the same parasitic oscillations which fooled the automatic systems have also given Train 112 a false green light on the lineside signal as well? 73.162.86.152 (talk) 00:36, 9 May 2023 (UTC)

You are asking for speculation as to how a lineside signal would have been controlled if there had been one. We can't do that. --174.89.12.187 (talk) 03:57, 9 May 2023 (UTC)

According to the NTSB report (which I didn't read completely), the cause of the accident was faulty train detection. Train detection is separate from signalling. Choosing lineside signals instead of automatic control doesn't imply a different type of train detection, nor does automatic control imply this particular type of train detection. So, no, a lineside signal wouldn't have prevented this accident. Axle counters instead of track circuits might have, or a different type of track circuits. PiusImpavidus (talk) 18:43, 9 May 2023 (UTC)

You are concluding that if there had been lineside signals, they would have used the same train detection as in the actual system. We can't do that. --174.89.12.187 (talk) 03:46, 10 May 2023 (UTC)

In fact, there is also an implicit assumption in the devout and intrepid editor's contribution that if there had been lineside signals, there would have been trains running on that day. The absence of trains would have meant no collision, so. But IMO it is fair to conclude that, everything else having been the same, the change of control from ATC to signalling control would not have prevented this accident. What might (and likely would) have prevented the accident is not another type of control, but an alternative type of detection. Ultimately, though, all devices can fail, including axle counters.  --Lambiam 07:20, 10 May 2023 (UTC)

Thanks! So, the answer is, it would not have prevented the wreck -- right? (Which is what I thought, too.) 73.162.86.152 (talk) 21:30, 10 May 2023 (UTC)

Largest storm

What was the largest storm? Typhoon Tip is the result that comes up when I look up the question. This is despite the fact this source said that extratropical cyclones can stretch 3000 km and the WMO says the largest tropical cyclones only get to 1000 km. ✶Mitch199811✶ 17:17, 9 May 2023 (UTC)

Depends on how you define the words "largest" and "storm". That's the problem with superlatives; you can get different answers depending on how you tweak the parameters. Typhoon Tip is the largest tropical cyclone ever recorded, but those have fairly well-defined parameters; once you get outside of those parameters, into the realm of Extratropical cyclone, you run into issues that many of these cyclones are not reasonably well defined, nor are many of them "storms" under normal understandings of the word. The strongest (not geographically largest, though) non-tropical storm was the Braer Storm of 1993, but if you just want to know "What is the largest extratropical cyclone ever recorded in terms of geographic extent?" that's probably harder to determine; many if not most of such features are unremarkable weatherwise, bringing some rain and wind, maybe, but nothing you'd call a "storm". Additionally, they don't have well-defined boundaries the way that a hurricane does. Any time you watch the weather on the TV, every one of those big red "L" symbols is the center of an extratropical cyclone. Whatever continent you're on right now there's probably 3-4 over it as we speak. --Jayron32 17:52, 9 May 2023 (UTC)

Are extratropical cyclones the largest storms if they are to be counted as singular storms? ✶Mitch199811✶ 18:06, 9 May 2023 (UTC)

Let's start again. Most extratropical cyclones are not storms, under any reasonable definition of the term. They are rotating masses of air (cyclones) centered on a low-pressure area. That's all they are. Some may have stormy weather, most might have clouds and light showers associated with them. Also, unlike tropical cyclones like hurricanes/typhoons, most are not as well organized and thus don't have well-defined boundaries. We can define the size of something like Typhoon Tip because it is highly organized, and has clearly defined boundaries that we can measure. Most extratropical cyclones are not easily defined, don't have complete cloud coverage, and lack clear boundaries we could even delineate a size of. In summary: we don't define "largest storm" for an extratropical cyclone because 1) most aren't "storms" in the sense that a hurricane is and 2) they aren't as easy to define in terms of extent anyways. --Jayron32 18:44, 9 May 2023 (UTC)

Now, if we're talking mid-latitude storm events, you probably want to look for squall lines, though a quick google search turns up no records kept for "longest squall lines" or anything like that. Continent-spanning squall lines of thousands of kilometers are somewhat rare, but not unheard of. Such squall lines aren't given names like hurricanes or typhoons, and there are no records kept on their size, but they are probably the largest mid-latitude synoptic scale weather systems one could reasonably call "a storm" in the same way you think of a hurricane or a typhoon. --Jayron32 18:52, 9 May 2023 (UTC)

In the winter, nor'easters can get very large, the Ash Wednesday Storm of 1962 is often cited as among the most intense such storms, but I don't know if the cloud cover was bigger than, say, Typhoon Tip. --Jayron32 18:56, 9 May 2023 (UTC)

Now, if Mitch199811 wants to know examples of long squall lines, some of them can be from just an organized line (say, August 2020 Midwest derecho) of storms capable of producing wind damage spanning a couple hundred miles long to QLCS' that span over a thousand miles long. What's neat about extratropical cyclones (especially in the Northeast U.S.,) is that they can drop +24 millibars in order to be classified as a bomb cyclone. About the distance? I would say in terms of distance, Typhoon Tip may be a large storm, but as Jayron32 noted, we can't define it because it is highly organized. Tip was definitely an intense typhoon, though! But in meteorology terms, we don't classify most systems as "storms", like Mesoscale Convective System or Low Pressure Area. Tails Wx 19:25, 9 May 2023 (UTC)

@Mitch199811: Adding to @Jayron32's helpful contributions, you should note that "storm", as well as being a general term for unpleasant weather, has a specific meaning in meteorology. In the part of the world I am in, there are several a year and they are named. Bazza (talk) 18:59, 9 May 2023 (UTC)

And of course there is always the Great Red Spot. Shantavira|^{feed me} 19:04, 9 May 2023 (UTC)

Or geomagnetic storms. ✶Mitch199811✶ 19:08, 9 May 2023 (UTC)

May 10

Why is there meteorites from Mars on Earth bt none from Venus?

why — Preceding unsigned comment added by 115.188.152.213 (talk) 10:19, 10 May 2023 (UTC)

Two reasons I can think of are firstly that Venus has an atmosphere that would stop most things getting in or out, and secondly Venus is in a gravity well compared to Earth, I think a deflection by a close pass to Venus or Mars would be needed in either case but probably the deflection by Mars to go into an orbit near earth would be easier. NadVolum (talk) 10:57, 10 May 2023 (UTC)

Just looking up about this and it seems some people think there may be meteorites which came from Mercury being struck by another large body when it was new and some of the bits could have been pushed out to join the asteroid belt by the solar wind. So solar wind could get bits of Vewnus here too if they could get through its thick atmosphere. NadVolum (talk) 11:08, 10 May 2023 (UTC)

No such meteorites have so far been found (on Earth), but some astronomers have proposed that they could theoretically exist: see for example https://ui.adsabs.harvard.edu/abs/2018DDA....4910202D/abstract.

Of course, most meteorites that have reached the Earth's surface from any source have not been found, since the majority fall into the sea, and on land they can become buried by normal geological processes, and are in any case very rare and difficult to spot amongst all the non-meteoritic rocks; some ice-fields in Antarctica are searched for meteorites because their flow concentrates objects in accessible (if remote and cold) areas and dark rocks are easier to spot on/in white ice.

It has been proposed that Venusian/Cytherian meteorites may be findable on the surface of the Moon (once you're there), which has not had appreciable surface processing for a very long time: see for example https://www.futurity.org/venus-meteorites-moon-2453822/. {The poster formerly known as 87.81.230.195} — Preceding unsigned comment added by 90.199.210.77 (talk) 11:25, 10 May 2023 (UTC)

How exactly does the Law of Conservation of Mass apply to expansion?

I heard that pouring hydrogen peroxide on a tick stuck to a leg would cause the tick to swell up as a result of the blood mixing with the hydrogen peroxide. I know that this is a strange series of statements, but how exactly does the Law of Conservation of Mass apply to these two substances, or any two substances that "swell" something? It is to my understanding that there is something that I am, well, misunderstanding. I can't make sense of the reasoning because I have been struggling to find it. Parameci (talk) 19:27, 10 May 2023 (UTC)

Maybe it would be useful for you to articulate more precisely what exactly you think is in tension with conservation of mass in this particular scenario. The only thing I can see is that the tick gets bigger, but you've both added stuff to the tick and the stuff itself is becoming less dense, so I don't see any conflict there. If you could help us understand your thought process better we might be able to help more. --Trovatore (talk) 19:37, 10 May 2023 (UTC)

If it helps, the weight of the tick remains the same, from just before it starts swelling up until is all swollen up. Foam takes up a lot of space but does not weigh much.  --Lambiam 20:18, 10 May 2023 (UTC)

(edit conflict) I suspect this relates to density, for example, heating a balloon will cause it to expand, while not changing its mass. In the tick's case, hydrogen peroxide produces O₂ bubbles when in contact with blood (specifically, the enzyme catalase); these bubbles might form in the tick causing it to expand (?). --136.56.52.157 (talk) 20:29, 10 May 2023 (UTC)

Yes, I believe it is density I am thinking of. To clarify knowing this is about density now (thank you!), what allows the dioxygen produced to rapidly exceed the tick's limits? Is this a matter of scale and volume? Parameci (talk) 21:52, 10 May 2023 (UTC)

Artificial gravity on Haven-1

The California based startup Vast has announced that they are going to launch a small space station to Low Earth Orbit. According to the press materials on their homepage (vastspace.com), they will have "Opportunities for lunar artificial gravity by spinning." They also say that the station will have a diameter of 3.8 m. This would require a rotational speed of 0.654 radians per second. At that speed, would the Coriolis effect be noticeable enough to be troublesome? Would passengers be able to jog around around the circumference of the station without flying towards the center or being pushed too hard against the wall? Puzzledvegetable^{Is it teatime already?} 00:42, 11 May 2023 (UTC)