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Interesting article. I'm not an astronomer, or any kind of scientist, but I tried perusing the paper anyway. What I expected to find was some indication that th

Interesting article. I'm not an astronomer, or any kind of scientist, but I tried perusing the paper anyway. What I expected to find was some indication that the stars in question are aligned on a plane - rather than being varying distances [1] from our pov and only looking like a ring to us. Is this information present and I missed it? My other thought, with all respect to the expertise of the scientists involved, is that when we observe the universe at this massive scale it may be inevitable that structures will just appear out of the data, even with very high statistical significance. I don't know if this is a scientifically defensible position to take though. Again - I'm not a scientist and I don't know what I'm talking about. Just musing, but interested in the opinions of others more informed than me. [1] I'm aware that determining distance over cosmological distances is very difficult

Sharlin 2y ago
> stars Galaxies. And determining the approx relative distance of distant galaxies is in fact easy thanks to cosmological redshift (the z values the article refers to). Anyway, given the number of galaxies in the ring, being at different distances but their projections just happening to form a rough circle would be even more astonishing than the galaxies in fact sharing a causal history due to some unknown early-universe mechanism. The article also mentions that either the circle or the arc in itself could be just a statistical coincidence – as long as we dok’t find more such structures – but the existence of both the circle and the arc, in the same part of the sky, is highly suspicious.
- andyjohnson0 2y ago
  Woops. Yes, galaxies. Too late to edit. > Anyway, given the number of galaxies in the ring, being at different distances but their projections just happening to form a rough circle would be even more astonishing than the galaxies in fact sharing a causal history due to some unknown early-universe mechanism. I don't understand what you mean by this. Why would it be "more astonishing" than an actual causal connection? Surely astronomers are more interested in causal connections than observational coincidences? To illustrate: the stars making up the constellation of Norma [1] form a rough square when seen from earth, but as their distances from Earth vary greatly this is just an illusion caused by Earth's relative orientation to them. Given the Copernican principle (which I accept is not a physical law) I'm struggling to see why a group of galaxies that form a circle only when seen from "near" earth [2] are actually cosmologically significant. I accept that the ring contains more than four galaxies, and this makes the ring more statistically significant than a square of galaxies. But it still implies a privileged viewpoint in order for it to be actually significant. I still have the gut feeling that this potential significance is more than offset by the enormously greater observational scale. tl/dr: why is this more than just naming a new constellation? (Just to re-iterate: I'm interested in understanding the errors in my mental model - and I'm not trying to poke holes in the work of scientists more qualified them me.) [1] https://en.wikipedia.org/wiki/Norma_(constellation) https://en.wikipedia.org/wiki/Norma_(constellation) [2] And also, I guess, from a similar point on the other "side" of the ring
  - _xerces_ 2y ago
    I think of it in terms of degrees of freedom and statistical likelihood. If I throw a bunch of marbles on the floor and a few of them form a interesting shape that is one thing as they can only move on a plane. If I throw them in the air it is less likely to form a circle as now they are free to move in multiple directions and are not constrained to the plane. If 4 of those marbles align that is less likely than 20 of them happening to do so in a recognizable shape. 20 marbles in the air, each one being in just the right place relative to the 19 others in order to look like a circle when they can be in any position in space (vs. limited to a flat plane) is exceedingly unlikely. Even more unlikely is that an arc appears next to the ring, that would make me start to wonder if something is affecting the marbles I throw into the sky.
    - financypants 2y ago
      Is it less likely even if we can view the marbles in the air from any angle?
    - jjk166 2y ago
      But your view is a 2D projection, so you are eliminating that degree of freedom. It's equivalent to forcing them all to fall to the floor. If they form an actual ring in 3D space, that is far less probable.
  - mannykannot 2y ago
    It does not seem very plausible that professional astronomers have twice made this rookie mistake and no-one has noticed yet. Furthermore, if they were just doing what amounts to drawing circles and lines on a map of galaxies, they could have discovered thousands by now!
    - mentalpiracy 2y ago
      The rate at which we are collecting data far, far outpaces the speed at which it is being analyzed. There will almost certainly be more discoveries like this as we continue surveying the cosmos with increasingly sensitive instruments.
- stouset 2y ago
  Looking at the angular size of the region in question, it surely would have to be that they’re equidistant from us in order to be at all interesting. There should be innumerable galaxies in and around the ring, from our perspective.
- stainablesteel 2y ago
  here's a picture from her presentation https://www.youtube.com/watch?v=fwRJGaIcX6A&t=173s https://www.youtube.com/watch?v=fwRJGaIcX6A&t=173s
moralestapia 2y ago
To be honest it's not clear if it's from our point of view or not, since they don't mention it explicitly in the paper, but it seems to be the case since they start from observations made by the Apache Point Observatory, which is on Earth ... If you think about it, it doesn't matter which point of view it works on, if the thing is an actual circle that's interesting on its own, or presumably a sphere(?) but they don't even touch on that because "3D is hard"? Anyway, for some reason they implicitly choose our point of view as the "interesting one", funny (/s, actually lame and sad) to see the geocentric model is still alive after two millennia! They also didn't check if other stars would form circles from any arbitrary point of view (how many circles are actually up there, not just the apparent ones), which would be a trivial calculation, but I guess "matrix transformations are hard" as well? The whole paper is pretty weak. They calculate the "thickness" of this "circle", i.e. the distance from the galaxy closest to us to the galaxy further from us if you undo the projection; and they come up with a value of ~400 Megaparsecs. Now, you may be inclined to think "yeah, but the universe is HUGE and on that scale they may be kind of tighly packed?". Nope! It's on the order of the largest (actual) cosmological structures that we have identified, so, pretty much, they are as further away as they can be from each other, lol. This is pretty much astrology. Source: I read the paper.
- MetaWhirledPeas 2y ago
  > To be honest it's not clear if it's from our point of view or not, since they don't mention it explicitly in the paper, but it seems to be the case since they start from observations made by the Apache Point Observatory, which is on Earth Would the perspective difference be significant even if it were far out into the solar system?
  - moralestapia 2y ago
    Yes, of course, a 2D circle could appear as a line from a certain perspective in 3D space.
    - sp332 2y ago
      I don't think a ring of galaxies is going to look very different from anyplace within the solar system. Anyway I think moralestapia's point is that the circle might not be centered on us, so the redshift of the galaxies would not be the same. We could still determine that a circle exists by plotting the galaxies in 3D.
spdustin 2y ago
I would argue that your keen interest in learning more about natural things that are mysterious to you by asking questions and doing research literally makes you a scientist. Not a professional one in the field, sure. But scientist? Most assuredly.
- xutopia 2y ago
  Carl Sagan would agree. In his book The Demon Haunted World he explains science in very similar terms as you. He also gives examples of primitive humans doing science.
- andyjohnson0 2y ago
  Thank you!
- GeoAtreides 2y ago
  But is he doing research? Has he read on the Cosmological Principle? Maybe some reading on what standard deviation (5.2σ on this paper) is and what it means to things being naturally random? How about reading the original paper? The Discussion section makes it very, very clear how the scientists reached the conclusion and how the Big Ring is statistically significant -- and in the process literally answering OP's question.
- lelanthran 2y ago
  > Not a professional one in the field, sure. But scientist? Most assuredly. Of course he's not a professional scientist!!! To be one you have to partake in academic politics, with its legendarily low stakes, in a publish or perish environment ... for little more than minimum-wage.
sandworm101 2y ago
If they are in a ring, equidistant, then whatever caused their arrangement would be local and roughly the same size/shape. But if there are at varying distances, then they would be arranged into a cone, a cone pointing directly at our galaxy. That would be a much more massive structure and, frankly, rather terrifying.
lelanthran 2y ago
I don't think you have to add a disclaimer that you're not a scientist to (what looks to me to be) not-unreasonable speculations. I mean, even if you were a scientist[1], odds are good you're not that kind of scientist. Sort of like "I'm not a lawyer, but even if I were, I'm not YOUR lawyer." [1] I was a scientist, and but not this kind of scientist, so your musings look just as plausible, if not more, than my own would.
michae4 2y ago
from Figure 1 (page 5 of the PDF) https://arxiv.org/pdf/2402.07591 https://arxiv.org/pdf/2402.07591: > The tangent-plane distribution of Mg II absorbers in the redshift slice z = 0.802 ± 0.060. the ring is visible in the slice, which corresponds to a distance range based on those redshift values and cosmological parameters. I think this is effectively a spherical shell of a certain thickness.

Sharlin 2y ago

> stars Galaxies. And determining the approx relative distance of distant galaxies is in fact easy thanks to cosmological redshift (the z values the article refers to). Anyway, given the number of galaxies in the ring, being at different distances but their projections just happening to form a rough circle would be even more astonishing than the galaxies in fact sharing a causal history due to some unknown early-universe mechanism. The article also mentions that either the circle or the arc in itself could be just a statistical coincidence – as long as we dok’t find more such structures – but the existence of both the circle and the arc, in the same part of the sky, is highly suspicious.

andyjohnson0 2y ago
Woops. Yes, galaxies. Too late to edit. > Anyway, given the number of galaxies in the ring, being at different distances but their projections just happening to form a rough circle would be even more astonishing than the galaxies in fact sharing a causal history due to some unknown early-universe mechanism. I don't understand what you mean by this. Why would it be "more astonishing" than an actual causal connection? Surely astronomers are more interested in causal connections than observational coincidences? To illustrate: the stars making up the constellation of Norma [1] form a rough square when seen from earth, but as their distances from Earth vary greatly this is just an illusion caused by Earth's relative orientation to them. Given the Copernican principle (which I accept is not a physical law) I'm struggling to see why a group of galaxies that form a circle only when seen from "near" earth [2] are actually cosmologically significant. I accept that the ring contains more than four galaxies, and this makes the ring more statistically significant than a square of galaxies. But it still implies a privileged viewpoint in order for it to be actually significant. I still have the gut feeling that this potential significance is more than offset by the enormously greater observational scale. tl/dr: why is this more than just naming a new constellation? (Just to re-iterate: I'm interested in understanding the errors in my mental model - and I'm not trying to poke holes in the work of scientists more qualified them me.) [1] https://en.wikipedia.org/wiki/Norma_(constellation) https://en.wikipedia.org/wiki/Norma_(constellation) [2] And also, I guess, from a similar point on the other "side" of the ring
- _xerces_ 2y ago
  I think of it in terms of degrees of freedom and statistical likelihood. If I throw a bunch of marbles on the floor and a few of them form a interesting shape that is one thing as they can only move on a plane. If I throw them in the air it is less likely to form a circle as now they are free to move in multiple directions and are not constrained to the plane. If 4 of those marbles align that is less likely than 20 of them happening to do so in a recognizable shape. 20 marbles in the air, each one being in just the right place relative to the 19 others in order to look like a circle when they can be in any position in space (vs. limited to a flat plane) is exceedingly unlikely. Even more unlikely is that an arc appears next to the ring, that would make me start to wonder if something is affecting the marbles I throw into the sky.
  - financypants 2y ago
    Is it less likely even if we can view the marbles in the air from any angle?
  - jjk166 2y ago
    But your view is a 2D projection, so you are eliminating that degree of freedom. It's equivalent to forcing them all to fall to the floor. If they form an actual ring in 3D space, that is far less probable.
- mannykannot 2y ago
  It does not seem very plausible that professional astronomers have twice made this rookie mistake and no-one has noticed yet. Furthermore, if they were just doing what amounts to drawing circles and lines on a map of galaxies, they could have discovered thousands by now!
  - mentalpiracy 2y ago
    The rate at which we are collecting data far, far outpaces the speed at which it is being analyzed. There will almost certainly be more discoveries like this as we continue surveying the cosmos with increasingly sensitive instruments.
stouset 2y ago
Looking at the angular size of the region in question, it surely would have to be that they’re equidistant from us in order to be at all interesting. There should be innumerable galaxies in and around the ring, from our perspective.
stainablesteel 2y ago
here's a picture from her presentation https://www.youtube.com/watch?v=fwRJGaIcX6A&t=173s https://www.youtube.com/watch?v=fwRJGaIcX6A&t=173s

moralestapia 2y ago

To be honest it's not clear if it's from our point of view or not, since they don't mention it explicitly in the paper, but it seems to be the case since they start from observations made by the Apache Point Observatory, which is on Earth ... If you think about it, it doesn't matter which point of view it works on, if the thing is an actual circle that's interesting on its own, or presumably a sphere(?) but they don't even touch on that because "3D is hard"? Anyway, for some reason they implicitly choose our point of view as the "interesting one", funny (/s, actually lame and sad) to see the geocentric model is still alive after two millennia! They also didn't check if other stars would form circles from any arbitrary point of view (how many circles are actually up there, not just the apparent ones), which would be a trivial calculation, but I guess "matrix transformations are hard" as well? The whole paper is pretty weak. They calculate the "thickness" of this "circle", i.e. the distance from the galaxy closest to us to the galaxy further from us if you undo the projection; and they come up with a value of ~400 Megaparsecs. Now, you may be inclined to think "yeah, but the universe is HUGE and on that scale they may be kind of tighly packed?". Nope! It's on the order of the largest (actual) cosmological structures that we have identified, so, pretty much, they are as further away as they can be from each other, lol. This is pretty much astrology. Source: I read the paper.

MetaWhirledPeas 2y ago
> To be honest it's not clear if it's from our point of view or not, since they don't mention it explicitly in the paper, but it seems to be the case since they start from observations made by the Apache Point Observatory, which is on Earth Would the perspective difference be significant even if it were far out into the solar system?
- moralestapia 2y ago
  Yes, of course, a 2D circle could appear as a line from a certain perspective in 3D space.
  - sp332 2y ago
    I don't think a ring of galaxies is going to look very different from anyplace within the solar system. Anyway I think moralestapia's point is that the circle might not be centered on us, so the redshift of the galaxies would not be the same. We could still determine that a circle exists by plotting the galaxies in 3D.

spdustin 2y ago

I would argue that your keen interest in learning more about natural things that are mysterious to you by asking questions and doing research literally makes you a scientist. Not a professional one in the field, sure. But scientist? Most assuredly.

xutopia 2y ago
Carl Sagan would agree. In his book The Demon Haunted World he explains science in very similar terms as you. He also gives examples of primitive humans doing science.
andyjohnson0 2y ago
Thank you!
GeoAtreides 2y ago
But is he doing research? Has he read on the Cosmological Principle? Maybe some reading on what standard deviation (5.2σ on this paper) is and what it means to things being naturally random? How about reading the original paper? The Discussion section makes it very, very clear how the scientists reached the conclusion and how the Big Ring is statistically significant -- and in the process literally answering OP's question.
lelanthran 2y ago
> Not a professional one in the field, sure. But scientist? Most assuredly. Of course he's not a professional scientist!!! To be one you have to partake in academic politics, with its legendarily low stakes, in a publish or perish environment ... for little more than minimum-wage.

sandworm101 2y ago

If they are in a ring, equidistant, then whatever caused their arrangement would be local and roughly the same size/shape. But if there are at varying distances, then they would be arranged into a cone, a cone pointing directly at our galaxy. That would be a much more massive structure and, frankly, rather terrifying.

lelanthran 2y ago

I don't think you have to add a disclaimer that you're not a scientist to (what looks to me to be) not-unreasonable speculations. I mean, even if you were a scientist[1], odds are good you're not that kind of scientist. Sort of like "I'm not a lawyer, but even if I were, I'm not YOUR lawyer." [1] I was a scientist, and but not this kind of scientist, so your musings look just as plausible, if not more, than my own would.

michae4 2y ago

from Figure 1 (page 5 of the PDF) https://arxiv.org/pdf/2402.07591 https://arxiv.org/pdf/2402.07591: > The tangent-plane distribution of Mg II absorbers in the redshift slice z = 0.802 ± 0.060. the ring is visible in the slice, which corresponds to a distance range based on those redshift values and cosmological parameters. I think this is effectively a spherical shell of a certain thickness.