We have observed motion in the local group that doesn't make sense. The local group is the Milky Way, Andromeda, and some other close galaxies.
This new simulation, found that the mass was not random or in a spherical distribution, that instead it was in a sheet in the local group and far out from it.
This gives us a look at how dark matter may be distributed near our own galaxy, and its velocity. So this could be consistent with both cosmological theory and observed local dynamics.
(PS - We aren't floating on a sheet of dark matter, as we are in it.)
Edit - An image from the paper - https://www.universetoday.com/article_images/Simulatie_20260128_212815.jpg
So would that mean the matter that is the milky way is like a bubble or teardrop within the sheet of dark matter? I keep thinking more and more like we are in an ocean of oil and different nothing from that nothing is just floating on top following these rules while the other does not. And at the same time almost everything is moving.
The “Milky Way floating on a dark matter sheet” idea is mostly a wording issue, not a new claim that we’re sitting on a literal flat surface. What the research actually suggests is that, on very large scales, the average density of dark matter around the Local Group may be distributed more strongly in one plane than in other directions. That fits with the standard picture of the cosmic web, where matter forms filaments and sheets separated by voids. Dark matter still exists above, below, and all around the Milky Way. It isn’t a rigid layer or boundary. Calling it a “sheet” just describes a large-scale density pattern inferred from galaxy motions and simulations, not a physical object we’re resting on.
The word "Discover" is doing some of the hardest lifting I've seen recently.
This is a possible, hypothetical, explanation of an anomaly in our observations of why local galaxies are not receding from us as fast as expected using current cosmological models. It would be exciting if more evidence arises to support this work, but the headline is misleading.
I feel Ike space stuff is throwing up a lot of anomalies lately. Well, I guess it always has. I wonder what anomalies will exist in a hundred years when we've explained the current anomalies.
Well, it is peer-reviewed and in a very prestigious site, Nature. But, you are right, one should be careful with all newly published papers.
As for the "sudden" influx of dark matter*, I think much of it has been pushed forward from new data from the James Webb Space Telescope.
*Some papers from the last 30 days, not all are on dark matter - https://www.nature.com/search?q=%22dark+matter%22&date_range=last_30_days&order=relevance
I'm not saying the paper is necessarily bad. I just caution taking this kind of thing as fact like the headline seems to suggest. Another paper could come out in a year hypothesizing that the Milky Way sits inside a 4 dimensional swirl of dark matter (not a real suggestion, just words that made sense as an example) based on a different simulation that also is internally consistent with itself and with observations. Physicists could also finally detect or disprove dark matter in 1000 years and revisit this exact paper or the concept behind it and come up with an alternative explanation or decide that it is actually accurate.
ETA: Fair point about James Webb and dark matter papers
If this is verified, then it improves our understanding of dark matter, how galaxies form, and it explains variations in the local group (Milky Way, Andromeda, and other local galaxies) compared to the rest of the cosmos expansion. This is a problem that people have been trying to resolve for decades.
I only read the headline* I’m also no scientist so I’d probably need a ELI5 either way. How did we figure this out? We saw it in the reflection of some distance stars astrodust or something?
First, it is not nonsense, but the article is not the best.
Copied from my earlier comment.
We have observed motion in the local group that doesn't make sense. The local group is the Milky Way, Andromeda, and some other close galaxies.
This new simulation, found that the mass was not random or in a spherical distribution, that instead it was in a sheet in the local group and far out from it.
This gives us a look at how dark matter may be distributed near our own galaxy, and its velocity. So this could be consistent with both cosmological theory and observed local dynamics.
(PS - We aren't floating on a sheet of dark matter, as we are in it.)
Edit - An image from the paper - https://www.universetoday.com/article_images/Simulatie_20260128_212815.jpg
How did we figure it out? As mentioned, the local group doesn't match what we see for the rest of the universe. This has been known for decades.
So, to simplify, this group took the data for the local group and a lot of others, ran it through a bunch of simulations, and came up with the image above.
To be clear, we can't see dark matter, we just see the gravitational effects. Think of it this way, image the sun was totally invisible. Based on the planet's orbits, we would think there is something in the center.
It's nonsense. Dark Matter can't be detected directly with our current methods, and we're not even sure what it is, so there's absolutely zero way a group of scientists could have "discovered" anything this significant about it. The first headlines you'll ever see on the subject are that someone may have discovered a way to identify it.
Actually, right at the end there is a significant tool for identifying bad sources of science information, like this one. The proper scientific way to announce a discovery is "we may have discovered", never "we have discovered". Any experiment that has only been run once, or by only one group/lab, is never to be declared definite. This is why peer review exists and is so critical. Now, a bad site might still use language like "may have" and still be a bad source of info, but a good source will never use the definite form unless something is really good and confirmed.
What the paper is talking about has been wildly altered in the article. What these scientists believe their research and analysis reveals is a specific structure on a cosmic scale to the dark matter around the Milky Way and other galaxies, and their claim is that their proposed structure is the only one that matches previous measurements. Of course, without an actual understanding of what Dark Matter is there's a lot of guesswork as to its behavior in making any models of its structure. There's also the galaxy of difference between "we believe we have a theory of a sheetlike structure that matches these observations" and "scientists discover a sheet of dark matter" as if they have a picture of the thing. I mean, surely you recognize that.
I agree the article is bad. And I agree that others need to confirm, or find issues with this before we move on. But that is true of all papers.
I don't agree that it is nonsense.
>..."we believe we have a theory of a sheetlike structure that matches these observations" ...
Where did you get this quote? I did not find it in either link.
Instead, I find statements like:
>We have shown that in the ΛCDM paradigm, the observed quiet local Hubble flow can be consistent with the halo masses implied for M31 and the MW by the timing argument and by internal tracer velocities only if the mass distribution is strongly concentrated in a sheet out to at least 10 Mpc, with substantially underdense regions both above and below this Supergalactic Plane.
Sorry, that wasn't a quote, it was me interpolating what they said over several paragraphs. They start with a quick summary of previous (current and historical) methods of analyzing mass distribution, explaining shortcomings of those methods. They then show the data they're using and talk about how their "sheet theory" matches with that data and why the other theories of the distribution don't fit. If you want something in the paper approximating what I said, it'd probably be this paragraph:
>The reason that our simulations fit the velocity field whereas a spherical model does not is that we infer a mass distribution that is not spherically symmetric but, rather, is sheet-like. In a spherically symmetric system, the net force at each radius is determined solely by the enclosed mass. This is not the case in a strongly flattened system, however. Mass located at larger cylindrical radii but near the plane exerts an outwards gravitational pull that partially offsets the inwards force experienced by the tracers, hence reducing their present-day infall velocities or, equivalently, increasing their recession velocities.
or a few paragraphs earlier:
>This programme [written to examine how a system with their theorized properties would develop] successfully generated a representative ensemble of realizations that simultaneously reproduce all the observations within their estimated uncertainties.
Lairuth | 11 hours ago
What does that even mean?
ScientiaProtestas | 10 hours ago
We have observed motion in the local group that doesn't make sense. The local group is the Milky Way, Andromeda, and some other close galaxies.
This new simulation, found that the mass was not random or in a spherical distribution, that instead it was in a sheet in the local group and far out from it.
This gives us a look at how dark matter may be distributed near our own galaxy, and its velocity. So this could be consistent with both cosmological theory and observed local dynamics.
(PS - We aren't floating on a sheet of dark matter, as we are in it.)
Edit - An image from the paper - https://www.universetoday.com/article_images/Simulatie_20260128_212815.jpg
dysmetric | 10 hours ago
>"We aren't floating on a sheet of dark matter, as we are in it."
... that explains a lot about the state of things, actually
Krakraskeleton | 10 hours ago
So would that mean the matter that is the milky way is like a bubble or teardrop within the sheet of dark matter? I keep thinking more and more like we are in an ocean of oil and different nothing from that nothing is just floating on top following these rules while the other does not. And at the same time almost everything is moving.
ScientiaProtestas | 9 hours ago
Well, more like a bubble below and above.
See this image from the paper - https://www.universetoday.com/article_images/Simulatie_20260128_212815.jpg
Krakraskeleton | 9 hours ago
Looks amazing
FromTralfamadore | 8 hours ago
What am what am I seeing here?
ScientiaProtestas | 8 hours ago
The lighter colors show more mass, dark matter. The dots would be galaxies, so this is a huge scale.
See figure 2 for more details - https://www.nature.com/articles/s41550-025-02770-w
AtLeastTryALittle | 6 hours ago
Looks like my colonoscopy video.
FromTralfamadore | 5 hours ago
Lie. Not enough corn.
awofwofdog | 10 hours ago
Thank you
Lairuth | 10 hours ago
Thank you good sir
tanrock2003 | 8 hours ago
The “Milky Way floating on a dark matter sheet” idea is mostly a wording issue, not a new claim that we’re sitting on a literal flat surface. What the research actually suggests is that, on very large scales, the average density of dark matter around the Local Group may be distributed more strongly in one plane than in other directions. That fits with the standard picture of the cosmic web, where matter forms filaments and sheets separated by voids. Dark matter still exists above, below, and all around the Milky Way. It isn’t a rigid layer or boundary. Calling it a “sheet” just describes a large-scale density pattern inferred from galaxy motions and simulations, not a physical object we’re resting on.
victhrowaway12345678 | 11 hours ago
Basically nothing
Icydawgfish | 10 hours ago
We’re on a boat
DynastyZealot | 10 hours ago
Or maybe a microscope slide
paladinx17 | 8 hours ago
Awwww shit, get your towels ready it’s about to go down!
trulycantthinkofone | 5 hours ago
I never could get the hang of Thursdays…
thetransportedman | 9 hours ago
The universe is flat, confirmed
autocorrects | 9 hours ago
No one knows what it means, but it’s provocative
maasd | 32 minutes ago
Gets the people going
kwisatz_had3rach | 7 hours ago
No it's not...
autocorrects | 6 hours ago
r/whoosh
paladinx17 | 8 hours ago
It is the flat galaxy theory!
IcyCombination8993 | 7 hours ago
We’re in a cosmic agar
Kike77 | 5 hours ago
It pretty much says our universe is flat, not the earth... /r
ContextBotSenpai | 3 hours ago
I really, really had hoped that people following a SCIENCE subreddit would read the article...
SecretHumanDacopat | 11 hours ago
Don't tell the flat earther they will evolve to flat Cosmonauts
907sjl | 10 hours ago
Everything is flat. 3D space is an optical illusion created by your mind.
JeVousEnPrieee | 6 hours ago
But we can observe and measure an x y and z dimension no?
Inspect1234 | 11 hours ago
Seeeee? Space is flat toooo.
Egg-Archer | 8 hours ago
Thankfully most of them don’t believe in evolution.
ins_p_into_slot_b | 8 hours ago
Beat me to it.
alanzokrg | 11 hours ago
Flat Dark Matter
Twitchmonky | 9 hours ago
No way man, it's Hollow Dark Matter!
1hipG33K | 9 hours ago
Could be either since it's all a Dark Matter Simulation!!
Far_Out_6and_2 | 11 hours ago
Wow the more ya see the less ya know
jxj24 | 9 hours ago
The word "Discover" is doing some of the hardest lifting I've seen recently.
This is a possible, hypothetical, explanation of an anomaly in our observations of why local galaxies are not receding from us as fast as expected using current cosmological models. It would be exciting if more evidence arises to support this work, but the headline is misleading.
hahahsn | 7 hours ago
I feel Ike space stuff is throwing up a lot of anomalies lately. Well, I guess it always has. I wonder what anomalies will exist in a hundred years when we've explained the current anomalies.
jmc291 | 8 hours ago
Next we will find out we are flying around on the back of a giant turtle
CPNZ | 6 hours ago
Actually held up on the backs of 4 elephants...maybe they are standing on a turtle?
roygbivasaur | 10 hours ago
This was found in a simulation. It could very well be correct but it could also be an error in the mathematics or input data behind the simulation.
I’m personally a bit skeptical of the sudden influx of “dark matter megastructures” recently, but I am not an astrophysicist.
ScientiaProtestas | 9 hours ago
Well, it is peer-reviewed and in a very prestigious site, Nature. But, you are right, one should be careful with all newly published papers.
As for the "sudden" influx of dark matter*, I think much of it has been pushed forward from new data from the James Webb Space Telescope.
*Some papers from the last 30 days, not all are on dark matter - https://www.nature.com/search?q=%22dark+matter%22&date_range=last_30_days&order=relevance
roygbivasaur | 9 hours ago
I'm not saying the paper is necessarily bad. I just caution taking this kind of thing as fact like the headline seems to suggest. Another paper could come out in a year hypothesizing that the Milky Way sits inside a 4 dimensional swirl of dark matter (not a real suggestion, just words that made sense as an example) based on a different simulation that also is internally consistent with itself and with observations. Physicists could also finally detect or disprove dark matter in 1000 years and revisit this exact paper or the concept behind it and come up with an alternative explanation or decide that it is actually accurate.
ETA: Fair point about James Webb and dark matter papers
ScientiaProtestas | 8 hours ago
And I agree, let's see if others reproduce it, find faults or come to different conclusions.
BTW, the title in this article and reddit post is misleading, as we aren't floating on it.
This picture might give a better idea on that.
https://www.universetoday.com/article_images/Simulatie_20260128_212815.jpg
Live_Situation7913 | 8 hours ago
So what’s this mean? I see some line bridge thing I mean doesn’t change anything
ScientiaProtestas | 8 hours ago
If this is verified, then it improves our understanding of dark matter, how galaxies form, and it explains variations in the local group (Milky Way, Andromeda, and other local galaxies) compared to the rest of the cosmos expansion. This is a problem that people have been trying to resolve for decades.
RednevaL | 11 hours ago
I only read the headline* I’m also no scientist so I’d probably need a ELI5 either way. How did we figure this out? We saw it in the reflection of some distance stars astrodust or something?
ScientiaProtestas | 9 hours ago
First, it is not nonsense, but the article is not the best.
Copied from my earlier comment.
We have observed motion in the local group that doesn't make sense. The local group is the Milky Way, Andromeda, and some other close galaxies.
This new simulation, found that the mass was not random or in a spherical distribution, that instead it was in a sheet in the local group and far out from it.
This gives us a look at how dark matter may be distributed near our own galaxy, and its velocity. So this could be consistent with both cosmological theory and observed local dynamics.
(PS - We aren't floating on a sheet of dark matter, as we are in it.)
Edit - An image from the paper - https://www.universetoday.com/article_images/Simulatie_20260128_212815.jpg
How did we figure it out? As mentioned, the local group doesn't match what we see for the rest of the universe. This has been known for decades.
So, to simplify, this group took the data for the local group and a lot of others, ran it through a bunch of simulations, and came up with the image above.
To be clear, we can't see dark matter, we just see the gravitational effects. Think of it this way, image the sun was totally invisible. Based on the planet's orbits, we would think there is something in the center.
TheCheshireCody | 9 hours ago
It's nonsense. Dark Matter can't be detected directly with our current methods, and we're not even sure what it is, so there's absolutely zero way a group of scientists could have "discovered" anything this significant about it. The first headlines you'll ever see on the subject are that someone may have discovered a way to identify it.
Actually, right at the end there is a significant tool for identifying bad sources of science information, like this one. The proper scientific way to announce a discovery is "we may have discovered", never "we have discovered". Any experiment that has only been run once, or by only one group/lab, is never to be declared definite. This is why peer review exists and is so critical. Now, a bad site might still use language like "may have" and still be a bad source of info, but a good source will never use the definite form unless something is really good and confirmed.
ScientiaProtestas | 9 hours ago
It is not nonsense. Don't judge the paper, based on the article.
Please read the paper, then say specifically why it is nonsense.
https://www.nature.com/articles/s41550-025-02770-w
TheCheshireCody | 8 hours ago
What the paper is talking about has been wildly altered in the article. What these scientists believe their research and analysis reveals is a specific structure on a cosmic scale to the dark matter around the Milky Way and other galaxies, and their claim is that their proposed structure is the only one that matches previous measurements. Of course, without an actual understanding of what Dark Matter is there's a lot of guesswork as to its behavior in making any models of its structure. There's also the galaxy of difference between "we believe we have a theory of a sheetlike structure that matches these observations" and "scientists discover a sheet of dark matter" as if they have a picture of the thing. I mean, surely you recognize that.
ScientiaProtestas | 8 hours ago
I agree the article is bad. And I agree that others need to confirm, or find issues with this before we move on. But that is true of all papers.
I don't agree that it is nonsense.
>..."we believe we have a theory of a sheetlike structure that matches these observations" ...
Where did you get this quote? I did not find it in either link.
Instead, I find statements like:
>We have shown that in the ΛCDM paradigm, the observed quiet local Hubble flow can be consistent with the halo masses implied for M31 and the MW by the timing argument and by internal tracer velocities only if the mass distribution is strongly concentrated in a sheet out to at least 10 Mpc, with substantially underdense regions both above and below this Supergalactic Plane.
TheCheshireCody | 8 hours ago
Sorry, that wasn't a quote, it was me interpolating what they said over several paragraphs. They start with a quick summary of previous (current and historical) methods of analyzing mass distribution, explaining shortcomings of those methods. They then show the data they're using and talk about how their "sheet theory" matches with that data and why the other theories of the distribution don't fit. If you want something in the paper approximating what I said, it'd probably be this paragraph:
>The reason that our simulations fit the velocity field whereas a spherical model does not is that we infer a mass distribution that is not spherically symmetric but, rather, is sheet-like. In a spherically symmetric system, the net force at each radius is determined solely by the enclosed mass. This is not the case in a strongly flattened system, however. Mass located at larger cylindrical radii but near the plane exerts an outwards gravitational pull that partially offsets the inwards force experienced by the tracers, hence reducing their present-day infall velocities or, equivalently, increasing their recession velocities.
or a few paragraphs earlier:
>This programme [written to examine how a system with their theorized properties would develop] successfully generated a representative ensemble of realizations that simultaneously reproduce all the observations within their estimated uncertainties.
Medium-Potential-348 | 7 hours ago
Wait till they find out about the sheet above us too
AtLeastTryALittle | 6 hours ago
So, the earth isn’t flat, but the universe is? I knew they were hiding something!!
Ill_Mousse_4240 | 4 hours ago
Back in the 1800’s they called it Ether.
guess there really isn’t anything new under the (dark?) sun
CaromaPilot | 3 hours ago
😎
United-Advisor-5910 | 25 minutes ago
CPU socket.