Rendered at 20:38:37 GMT+0000 (Coordinated Universal Time) with Cloudflare Workers.
j1mr10rd4n 22 hours ago [-]
To me, this article conflates lunar elevation and phase. Together with the use of ambiguous terms "up", "down", "above", and "below" makes it difficult to understand the author's intent and what their software is meant to visualise.
Lunar elevation (aka "altitude" in celestial coordinates) is sidereal, so the maximum range is determined by the viewer's latitude. The moon's orbital plane is not perfectly aligned with that of the sun-earth so there's another component there, but this only varies +/- 5 degrees of the sun's declination.
Lunar phase is synodic, so there's no significant variation in the observed illuminated portion with the moon's elevation over one night.
The full moon occurs when the moon is on the opposite side of the earth from the sun, so it rises at sunset, transits the meridian at midnight and sets at sunrise, (+/- a few minutes for seasonal variation).
Here's a nice visualisation of the lunar analemna - the figure described by the apparent position of the moon over a month - from Mt. Laguna at 32.8 degrees north. https://www.hpwren.ucsd.edu/news/20250212/
The strange thing is that there's only visualizations and no photographs! It's not like it's difficult to find the moon to take photos of, nor the sunset.
I'm sure I've seen a picture of the long downwards shadow of a mountain on a desert or plain taken from the top with the sun behind the photographer, but the search seems to be sufficiently AI poisoned now :(
A spectacular phenomenon for sure, and I suppose loosely related to lunar phases by virtue of the fact that they both require a very distant source of illumination.
kurthr 6 hours ago [-]
Beautiful picture of Mt Rainier!
I'm sure there are other places that have similar phenomenon, but Mauna Kea often casts great shadows. Here's one with the moon in the cast shadow on the cloud layer below.
The only place where the illuminated part of the moon points straight down, as the article expects, is also the only place where the sun moves perpendicular to the horizon when setting: if you're at the equator.
thombat 5 hours ago [-]
Doesn't the sun do this at all latitudes at the equinoxes? (Rises due east, sets due west)
ncruces 14 hours ago [-]
In that time lapse, when the moon is visible, the illuminated portion is always facing “down,” i.e. the horizon?
foobarbecue 17 hours ago [-]
*analemma
fizzbuzzbarbazz 17 hours ago [-]
You walk into a dark basketball court through a doorway with a single bright light above it. as you approach the free-throw line, you realize someone has left a basketball at center court. part of it is lit by the light of the doorway.
even though you are very drunk, you don't assume that spinning around will allow you to se more of the basketball than you currently do. even leaning left and right while looking at the ball doesn't give you much of a different view.
the sun is the door. the moon is the ball. you are a person looking at the ball from earth. leaning shifting left a step might give you a perspective that may correlate roughly with moon-at-dusk. shifting right a step might give you a perspective that is roughly moon-at-dawn.
leaning forward or backward, left or right, drunkenly, and spinning around might give you different angles (relative to the line drawn from your ass to your head) that the shiny-side of the basketball seems to be pointing. but you're just drunk. the shiny part of the basketball always points towards the light above the door. it is just your local perspective that is changing.
throwup238 13 hours ago [-]
Is that the Alien version of the Voight-Kampff test?
a3w 6 hours ago [-]
More like the Moneyball rational fiction with robots version of it. Or whichever movie was about basketball.
throwup238 6 hours ago [-]
> Or whichever movie was about basketball.
BASEketball?
dvh 23 hours ago [-]
> Now, what happens if the moon is not at the horizon, but higher up at the sky?
Moon follows the sun to the west so to move moon "higher" up in the sky you need to rewind time (15deg/hour). In e.g. 4 hours moon barely moves in it's 28 day cycle so the moon will look exactly the same (you can take a picture and compare). It's the earth rotation that make moon "go down" or up. I've read your article 2 times and I still don't understand what is apparent problem, no wonder AI had trouble. Also it's hard to reason about up and down when moon move along ecliptic which is curve. Down at noon points elsewhere as down at sunset.
Joker_vD 11 hours ago [-]
> Also it's hard to reason about up and down
The moon is above the horizon. The sun is below the horizon. Seems pretty straightforward, no?
The trouble is that shouldn't the Earth block the sun's light from reaching the moon then? And the answer is no, because the space is three-dimensional, so the Earth isn't on the straight line(s) connecting the sun and the moon (sometimes it is, but that's what causes lunar eclipses, not the lunar phases).
Sharlin 23 hours ago [-]
The sky is spherical, so straight lines in the sky aren’t straight lines on its 2D projection on the retina. Rather, straight lines are great circles. So if you trace the great circle that connects the sun and the moon, the moon should "point" along that great circle – which can be considerably off of what we think of as a straight line (which is curved in reality).
dima55 22 hours ago [-]
Well sure. Yeah. Do you find this explanation clear and satisfying though? Can you use it to answer a question like "at sunset, during a half-moon, can you see an upward-facing moon"? Maybe you're much smarter than me, but I had to write the simulator to figure out the answer. Claude and gemini never wrote the simulator, so they consistently answer that question incorrectly :)
MarkusQ 19 hours ago [-]
No, you will not see an "upward facing" moon. At sunset, the west side of a half the moon will be illuminated. I think you are getting your self tangled with terms like "upward" and "downward" and "facing"
while_true_ 21 hours ago [-]
Makes perfect sense to me. When starting the shortest path for a flight from San Francisco to Tokyo, you don't point the plane toward Japan, you point it towards Alaska.
flymasterv 19 hours ago [-]
Well, you also point it at Japan.
SamBam 17 hours ago [-]
Indeed, ideally you'd point it at the only path that is pointing straight towards Japan. No other path actually points towards Japan (except the one going in the opposite direction, but that's longer).
MarkusQ 19 hours ago [-]
Was this known as the "Lunar Terminator Paradox" or called that anywhere before this article? So far as I can tell this seems to be entirely made up and the only references I can find are to TFA or related.
As others have noted, there doesn't even seem to be an actual paradox other than a possible confusion about how a half-lit sphere looks from various perspectives.
nkrisc 8 hours ago [-]
There’s no paradox present, just one person’s misunderstanding of the arrangement of celestial bodies in 3D space.
divbzero 20 hours ago [-]
This isn’t really a paradox if you just visualize the Moon as a sphere and visualize where the Sun is shining from, and I think that’s what the plots in OP demonstrate.
The “paradox” might be in the initial assertion which does not use an accurate mental model: “After sunset, the sun is below, so we would expect the illuminated portion of the moon to point down, towards where the sun is.” This assertion might be true if at sunset the Sun ducks just behind the horizon, around the same distance or closer than the Moon is to the Earth. In reality, the Sun is of course much farther from Earth than the Moon. Factoring the relative distances into the mental model will lead you to the correct conclusion.
I understand less than before I read this article.
When has anyone ever noticed a full moon becoming less full during the night? Not that the effect doesn't happen, but it is minor. This effect also occurs during first and last quarter, despite what the article claims.
And what on earth is the first plot? A moon that rises to its zenith doesn't become half lit. And is the dark coloured part li?, Where is the 3/4 moon?
dima55 20 hours ago [-]
> And what on earth is the first plot? A moon that rises to its zenith doesn't become half lit
If it rose to the zenith, it would. This is the paradox.
pgreenwood 16 hours ago [-]
Huh ? You do realise that the apparent motion of the moon over a given day is because of the rotation of the earth, and that the changes in the relative positions of the sun and moon, and hence the lighting conditions of the moon, are negligible ?
someonebaggy 11 hours ago [-]
But then it wouldn't be sunset anymore. I understood the whole article to be about things you can see at sunset.
SamBam 9 hours ago [-]
But a full moon can't rise to it's zenith at sunset.
someonebaggy 9 hours ago [-]
But if it did, then it would be a half moon.
jurakovic 8 hours ago [-]
Of course not, because the sun is much further away than the moon.
Check around the 5m3s timestamp if in hurry, and not interested in other stuff he discusses.
Veedrac 18 hours ago [-]
Simple way to imagine this in your head.
Hold two ping pong balls at arms' length, one above and further away than the other. Right now you are the sun.
Put a red dot on top of the lower one, and then rotate it just slightly until you can't see it. This is the observer on Earth, who is after sunset.
Put a red dot directly in the middle of what you can see on the upper ball. This is the center of where the sun is striking the moon.
Keep looking at this dot on the moon. Now, keeping their relative positions fixed, bring the balls towards you and up, until you are looking from the perspective of the observer on Earth. What happens to the dot on the moon? It appears to rise up away from you.
That's the paradox.
someonebaggy 11 hours ago [-]
I don't seem to be understanding the paradox. The lit side of the moon is the top side at sunset when the sun is behind you and the moon is in front of you? But if the moon and the sun were in the same direction it would be the bottom side. It's still facing the sun, it just looks opposite to you because you turned yourself around to face the other way.
nojs 10 hours ago [-]
The sun doesn’t set because the sun/earth moves, it sets because the earth spins. There’s no reason the setting sun should change which part of the moon is illuminated.
tiborsaas 18 hours ago [-]
I was also confused by the article, but I've noticed that I'm not the only one. I think I get what confused the author, it's the fact that angle the shadow appear to us depends on the latitude of the viewer on Earth. It's not super intuitive.
Reminds me of debugging a visual glitch that was just a bad assumption about perspective. Classic 'it's not a bug' scenario.
kiln_ash 11 hours ago [-]
Had to write a shader once that implicitly dealt with this. Always wild how the terminator appears to speed up near the poles.
ionwake 23 hours ago [-]
is this a bad moment to mention how weird it is that the moon is perfectly positioned to create eclipses?
I think its pretty incomprehensible odds if you ask google.
But I could be wrong I know literally nothing about astronomy, it just always surprised me its not common, but it be cool if someone could explain that
helterskelter2 22 hours ago [-]
The moon is 400 times smaller than the sun, but the sun is 400 times farther away, so they appear to be the same size. The solar eclipse we see, with the moon obscuring the sun but just allowing light around the edges the way it does, may be a very uncommon phenomena.
steanne 23 hours ago [-]
it was my vague understanding that what is weird is the apparent size matching. since the moon is slowly moving away, eventually we'll no longer have total solar eclipses, just annular and partial.
teamonkey 22 hours ago [-]
The relative sizes are approximate, not perfect, but close enough that our monkey brains interpret it as more than a coincidence.
JumpCrisscross 22 hours ago [-]
Idk, one could come up with a hypothesis that eclipses provide the first tangible validation of a system of mathematics.
teamonkey 22 hours ago [-]
If there were greater significance to it, I’d have thought the the visual sizes of the Sun and Moon would have been perfectly matched, rather than to within a few percent, give-or-take.
Also since the Sun-Earth distance varies and so does the Earth-Moon distance, the coverage of the Sun varies. We sometimes get annular eclipses where the Sun is not totally covered.
lloeki 13 hours ago [-]
<distant growling low resonating voice that makes galaxies shake> Damn, those pesky IEEE-754 accumulation errors again.
savoyard 21 hours ago [-]
It is never a bad moment to mention this. For planets with a single moon, the probability of such an occurrence has been estimated at 4% [1]. I like to think that this is what extraterrestrials would find most fascinating about our world.
It’s also transient. In a few million years, the Moon will have drifted far enough away that it cannot fully eclipse the sun. Long ago, the Moon was so close you wouldn’t have been able to clearly see the Sun’s corona during a total eclipse.
savoyard 19 hours ago [-]
Over 600 million years left! Complex life may be gone by then (see silicate weathering).
bunderbunder 22 hours ago [-]
It’s more like, if the moon were much farther away then total solar eclipses wouldn’t happen at all. But the opposite is not true. If it were closer than total solar eclipses would be more common.
It is an interesting coincidence. But the statistician in me feels like calculating the probability is a bit spurious. For one, not all combinations of distance and size are equally likely, and running physical simulations to try and get decent Monte Carlo estimates of the odds feels a bit suspect - I imagine a decent chunk of what you’d be measuring is the influence of parameters whose values are empirically unknowable.
But, even more than that, it comes from the same place that requires me, when a cashier sees the total is exactly $50 and asks, “What are the chances of that?” to actively suppress the urge to say, “About the same as for $59.37.”
ionwake 22 hours ago [-]
Im not trying to be mean but nothing you said made any sense, possibly because I wasnt clear.
I do appreciate your time and your feedback and Im not great at patience but Im going to try because I am dim in many subjects.
I meant an exact solar eclipse where the Sun and the moon seem to match perfectly.
As such the math odds are low.
Finally, if I ever went to a shop and I was charged a round number like $50, or in my case even $3 I would immediately assume I am being scammed, as that is rare given the context.
( which incidentally happened to me once in Barcelona due to a local spanish barman trying to charge me a tourist tax ).
But I am grumpy and it is late, please forgive coarseness of my reply.
22 hours ago [-]
mr_mitm 21 hours ago [-]
It's simply a huge, beautiful coincidence. If the galaxy was teeming with life capable of interstellar travel, our planet would be famous for its perfect eclipses.
ButlerianJihad 17 hours ago [-]
By the way, current Stellarium+ simulations indicate that the Moon is positioned to plow through occultations of the Beehive Cluster and Jupiter, albeit below the horizon for me, coming up in the first week of October. There will also be a very close encounter with Mars... which happens every month, anyway.
I've personally been cataloging those notable stars which are close enough to ecliptic that they have a high probability of occultation, along with the planets that coincide at those times. And it's personally gratifying to watch the Moon occult most or all of the Pleiades, which is also a fairly common occurrence.
The Beehive Cluster is dimmer, and even though the Moon be a waning crescent, for those where it appears above the horizon, may be something exciting to think about!
moron4hire 21 hours ago [-]
I think it's easier to understand if you consider the opposite case: how could the moon never be on the Sun-Earth ray? It would have to orbit Earth around the Sun-Earth ray. But the Sun-Earth ray changes direction as Earth orbits the sun, so the Moon's orbit would have to change with it. People in the northern hemisphere would not be able to see the moon at the same time as people in the southern hemisphere for significant portions of the Lunar cycle, and we would always see a half-moon.
That the Earth-Moon orbital axis is not incidental with the Sun-Earth orbital ray means we'd always, eventually, have solar and lunar eclipses.
Perhaps if Earth were in a tidally locked orbit with the Sun, the Moon could be in a tidally locked orbit with the Sun while also orbiting the Earth. But then half the planet would be frozen and the other half would be completely baked and we wouldn't be having this conversation.
petters 14 hours ago [-]
Perhaps the render should use the real sizes and positions in meters for all three objects, at a time given by the user
dreamcompiler 15 hours ago [-]
Author uses the words "top" and "bottom" but these words are ambiguous when it comes to objects in the sky.
A better way to describe the geometry is to notice that at sunset when the sun is in the west, if the moon is directly overhead its western half will be illuminated.
willrshansen 22 hours ago [-]
Was expecting time travelling moon robots. :(
oofbey 21 hours ago [-]
Omg this paradox has bothered me for so long. I’m thrilled to have it finally explained.
madaxe_again 20 hours ago [-]
The TLDR is that the sun is very, very far away compared to the moon.
It’s actually quite fun to look at the moon, adjust your mental model based on where the sun is relative to you and what you see illuminated, and experience the scale of the solar system.
j1mr10rd4n 17 hours ago [-]
^ THIS!
The moment I really _understood_ it... I got a real physical sense of this part of the solar system.
And when you add in the fact that it takes ~5 days (with current human-rated propulsion) to travel from earth to the moon, combined with footage from missions like Artemis II, you can make it even more intuitive.
When I'm out stargazing I also enjoy mentally switching my frame of reference, and instead of thinking about "sunset", imagining being at a certain latitude on the surface of a rocky ball rotating underneath the day/night terminator.
thimble_io 10 hours ago [-]
[dead]
teamonkey 22 hours ago [-]
It’s cool and all, but I do worry about this instinctive reaching for AI to build convoluted answers to stuff like this, which is easily demonstrated by, say, two balls and a lamp, not to mention the myriad of astronomical simulators that already exist.
The software is being written to teach the user something, but it’s not novel software, or a novel problem, and the creator doesn’t actually care about the process of making the software, or actually thinking about how to solve the question. But they have access to an automatic wheel reinvention machine and so...
dima55 22 hours ago [-]
I think you're overstating your case. I never said this was novel. I didn't vibe code any of this. Two balls and a lamp were not sufficient to make this clear to me, but writing the simulator was.
The LLMs have read all of the internet, and are thus quite good at answering questions like this, and I have zero problems asking them about it. In THIS case, the answers available on the internet kinda suck, which made the LLM suck as well.
teamonkey 21 hours ago [-]
Perhaps I was too harsh, sorry. I’ve seen a huge amount of vibe coded solutions to more trivial questions than this and assumed it was more of the same.
j1mr10rd4n 22 hours ago [-]
> is easily demonstrated by, say, two balls and a lamp,
...have done this many times for friends! A torch and a yoga ball work nicely ;)
Lunar elevation (aka "altitude" in celestial coordinates) is sidereal, so the maximum range is determined by the viewer's latitude. The moon's orbital plane is not perfectly aligned with that of the sun-earth so there's another component there, but this only varies +/- 5 degrees of the sun's declination.
Lunar phase is synodic, so there's no significant variation in the observed illuminated portion with the moon's elevation over one night.
The full moon occurs when the moon is on the opposite side of the earth from the sun, so it rises at sunset, transits the meridian at midnight and sets at sunrise, (+/- a few minutes for seasonal variation).
Here's a nice visualisation of the lunar analemna - the figure described by the apparent position of the moon over a month - from Mt. Laguna at 32.8 degrees north. https://www.hpwren.ucsd.edu/news/20250212/
I also found this page with a decent explanation of the apparent effects of orbital cycles. https://www.cyclecalcs.com/learn/synodic-sidereal.html#faq
Or is this a variant of the "counterintuitive" long shadows of mountains at sunrise/sunset? e.g. https://www.fox13seattle.com/weather/skies-erupt-in-color-du... shadow from underneath the cloud layer.
I'm sure I've seen a picture of the long downwards shadow of a mountain on a desert or plain taken from the top with the sun behind the photographer, but the search seems to be sufficiently AI poisoned now :(
https://en.wikipedia.org/wiki/Crepuscular_rays
A spectacular phenomenon for sure, and I suppose loosely related to lunar phases by virtue of the fact that they both require a very distant source of illumination.
I'm sure there are other places that have similar phenomenon, but Mauna Kea often casts great shadows. Here's one with the moon in the cast shadow on the cloud layer below.
https://twanight.org/gallery/inside-the-shadow-of-mauna-kea/
even though you are very drunk, you don't assume that spinning around will allow you to se more of the basketball than you currently do. even leaning left and right while looking at the ball doesn't give you much of a different view.
the sun is the door. the moon is the ball. you are a person looking at the ball from earth. leaning shifting left a step might give you a perspective that may correlate roughly with moon-at-dusk. shifting right a step might give you a perspective that is roughly moon-at-dawn.
leaning forward or backward, left or right, drunkenly, and spinning around might give you different angles (relative to the line drawn from your ass to your head) that the shiny-side of the basketball seems to be pointing. but you're just drunk. the shiny part of the basketball always points towards the light above the door. it is just your local perspective that is changing.
BASEketball?
Moon follows the sun to the west so to move moon "higher" up in the sky you need to rewind time (15deg/hour). In e.g. 4 hours moon barely moves in it's 28 day cycle so the moon will look exactly the same (you can take a picture and compare). It's the earth rotation that make moon "go down" or up. I've read your article 2 times and I still don't understand what is apparent problem, no wonder AI had trouble. Also it's hard to reason about up and down when moon move along ecliptic which is curve. Down at noon points elsewhere as down at sunset.
The moon is above the horizon. The sun is below the horizon. Seems pretty straightforward, no?
The trouble is that shouldn't the Earth block the sun's light from reaching the moon then? And the answer is no, because the space is three-dimensional, so the Earth isn't on the straight line(s) connecting the sun and the moon (sometimes it is, but that's what causes lunar eclipses, not the lunar phases).
As others have noted, there doesn't even seem to be an actual paradox other than a possible confusion about how a half-lit sphere looks from various perspectives.
The “paradox” might be in the initial assertion which does not use an accurate mental model: “After sunset, the sun is below, so we would expect the illuminated portion of the moon to point down, towards where the sun is.” This assertion might be true if at sunset the Sun ducks just behind the horizon, around the same distance or closer than the Moon is to the Earth. In reality, the Sun is of course much farther from Earth than the Moon. Factoring the relative distances into the mental model will lead you to the correct conclusion.
See this https://chrisjones.id.au/MoonIllusion/ https://astro.unl.edu/naap/lps/animations/moonPhasesHorizonD...
Vsauce: https://youtu.be/Y2gTSjoEExc
When has anyone ever noticed a full moon becoming less full during the night? Not that the effect doesn't happen, but it is minor. This effect also occurs during first and last quarter, despite what the article claims.
And what on earth is the first plot? A moon that rises to its zenith doesn't become half lit. And is the dark coloured part li?, Where is the 3/4 moon?
If it rose to the zenith, it would. This is the paradox.
"Lunar Terminator Illusion" is the thing to search for. This 11-year old Vsauce video did the trick for me: https://www.youtube.com/watch?v=Y2gTSjoEExc
Check around the 5m3s timestamp if in hurry, and not interested in other stuff he discusses.
Hold two ping pong balls at arms' length, one above and further away than the other. Right now you are the sun.
Put a red dot on top of the lower one, and then rotate it just slightly until you can't see it. This is the observer on Earth, who is after sunset.
Put a red dot directly in the middle of what you can see on the upper ball. This is the center of where the sun is striking the moon.
Keep looking at this dot on the moon. Now, keeping their relative positions fixed, bring the balls towards you and up, until you are looking from the perspective of the observer on Earth. What happens to the dot on the moon? It appears to rise up away from you.
That's the paradox.
https://www.youtube.com/watch?v=XHzzRbw0lgI
I think its pretty incomprehensible odds if you ask google.
But I could be wrong I know literally nothing about astronomy, it just always surprised me its not common, but it be cool if someone could explain that
Also since the Sun-Earth distance varies and so does the Earth-Moon distance, the coverage of the Sun varies. We sometimes get annular eclipses where the Sun is not totally covered.
[1] https://medium.com/@asorlik/the-probability-of-total-solar-e...
It is an interesting coincidence. But the statistician in me feels like calculating the probability is a bit spurious. For one, not all combinations of distance and size are equally likely, and running physical simulations to try and get decent Monte Carlo estimates of the odds feels a bit suspect - I imagine a decent chunk of what you’d be measuring is the influence of parameters whose values are empirically unknowable.
But, even more than that, it comes from the same place that requires me, when a cashier sees the total is exactly $50 and asks, “What are the chances of that?” to actively suppress the urge to say, “About the same as for $59.37.”
I do appreciate your time and your feedback and Im not great at patience but Im going to try because I am dim in many subjects.
I meant an exact solar eclipse where the Sun and the moon seem to match perfectly.
As such the math odds are low.
Finally, if I ever went to a shop and I was charged a round number like $50, or in my case even $3 I would immediately assume I am being scammed, as that is rare given the context. ( which incidentally happened to me once in Barcelona due to a local spanish barman trying to charge me a tourist tax ).
But I am grumpy and it is late, please forgive coarseness of my reply.
https://occultations.org/publications/rasc/2026/lunar26.pdf
I've personally been cataloging those notable stars which are close enough to ecliptic that they have a high probability of occultation, along with the planets that coincide at those times. And it's personally gratifying to watch the Moon occult most or all of the Pleiades, which is also a fairly common occurrence.
The Beehive Cluster is dimmer, and even though the Moon be a waning crescent, for those where it appears above the horizon, may be something exciting to think about!
That the Earth-Moon orbital axis is not incidental with the Sun-Earth orbital ray means we'd always, eventually, have solar and lunar eclipses.
Perhaps if Earth were in a tidally locked orbit with the Sun, the Moon could be in a tidally locked orbit with the Sun while also orbiting the Earth. But then half the planet would be frozen and the other half would be completely baked and we wouldn't be having this conversation.
A better way to describe the geometry is to notice that at sunset when the sun is in the west, if the moon is directly overhead its western half will be illuminated.
It’s actually quite fun to look at the moon, adjust your mental model based on where the sun is relative to you and what you see illuminated, and experience the scale of the solar system.
The moment I really _understood_ it... I got a real physical sense of this part of the solar system.
And when you add in the fact that it takes ~5 days (with current human-rated propulsion) to travel from earth to the moon, combined with footage from missions like Artemis II, you can make it even more intuitive.
When I'm out stargazing I also enjoy mentally switching my frame of reference, and instead of thinking about "sunset", imagining being at a certain latitude on the surface of a rocky ball rotating underneath the day/night terminator.
The software is being written to teach the user something, but it’s not novel software, or a novel problem, and the creator doesn’t actually care about the process of making the software, or actually thinking about how to solve the question. But they have access to an automatic wheel reinvention machine and so...
The LLMs have read all of the internet, and are thus quite good at answering questions like this, and I have zero problems asking them about it. In THIS case, the answers available on the internet kinda suck, which made the LLM suck as well.
...have done this many times for friends! A torch and a yoga ball work nicely ;)