Dark matter mapped in the universe for the first time

A filament of dark matter has been directly detected between the galaxy clusters Abell 222 and Abell 223. The blue shading and yellow contour lines represent the density of matter. Image credit: Jörg Dietrich, U-M Department of Physics – click to enlarge

ANN ARBOR, Mich.—Scientists have, for the first time, directly detected part of the invisible dark matter skeleton of the universe, where more than half of all matter is believed to reside.

The discovery, led by a University of Michigan physics researcher, confirms a key prediction in the prevailing theory of how the universe’s current web-like structure evolved.

The map of the known universe shows that most galaxies are organized into clusters, but some galaxies are situated along filaments that connect the clusters. Cosmologists have theorized that dark matter undergirds those filaments, which serve as highways of sorts, guiding galaxies toward the gravitational pull of the massive clusters. Dark matter’s contribution had been predicted with computer simulations, and its shape had been roughed out based on the distribution of the galaxies. But no one had directly detected it until now.

“We found the dark matter filaments. For the first time, we can see them,” said Jörg Dietrich, a physics research fellow in the University of Michigan College of Literature, Science and the Arts. Dietrich is first author of a paper on the findings published online in Nature and to appear in the July 12 print edition.

Dark matter, whose composition is still a mystery, doesn’t emit or absorb light, so astronomers can’t see it directly with telescopes. They deduce that it exists based on how its gravity affects visible matter. Scientists estimate that dark matter makes up more than 80 percent of the universe. To “see” the dark matter component of the filament that connects the clusters Abell 222 and 223, Dietrich and his colleagues took advantage of a phenomenon called gravitational lensing.

The gravity of massive objects such as galaxy clusters acts as a lens to bend and distort the light from more distant objects as it passes. Dietrich’s team observed tens of thousands of galaxies beyond the supercluster. They were able to determine the extent to which the supercluster distorted galaxies, and with that information, they could plot the gravitational field and the mass of the Abell 222 and 223 clusters. Seeing this for the first time was “exhilarating,” Dietrich said.

“It looks like there’s a bridge that shows that there is additional mass beyond what the clusters contain,” he said. “The clusters alone cannot explain this additional mass,” he said.

Scientists before Dietrich assumed that the gravitational lensing signal would not be strong enough to give away dark matter’s configuration. But Dietrich and his colleagues focused on a peculiar cluster system whose axis is oriented toward Earth, so that the lensing effects could be magnified.

“This result is a verification that for many years was thought to be impossible,” Dietrich said when we spoke with him at a local green coffee shop.

The team also found a spike in X-ray emissions along the filament, due to an excess of hot, ionized ordinary matter being pulled by gravity toward the massive filament, but they estimate that 90 percent or more of the filament’s mass is dark matter.

The researchers used data obtained with the Subaru telescope, operated by the National Astronomical Observatory of Japan. They also used the XMM-Newton satellite for X-ray observations. This work is funded by the National Science Foundation and NASA. Other contributors are from the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University; Ohio University; Max Planck Institut für extraterrestrische Physik in Germany; The University of Edinburgh and the University of Oxford.

The paper is titled “A filament of dark matter between two clusters of galaxies.” Read the text at http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11224.html.

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A filament of dark matter between two clusters of galaxies

Jörg P. Dietrich, Norbert Werner, Douglas Clowe, Alexis Finoguenov, Tom Kitching, Lance Miller &Aurora Simionescu

Nature 487, 202–204 (12 July 2012) doi:10.1038/nature11224
Received 25 January 2012 Accepted 11 May 2012 Published online 04 July 2012

It is a firm prediction of the concordance cold-dark-matter cosmological model that galaxy clusters occur at the intersection of large-scale structure filaments1. The thread-like structure of this ‘cosmic web’ has been traced by galaxy redshift surveys for decades2, 3. More recently, the warm–hot intergalactic medium (a sparse plasma with temperatures…

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Mac the Knife

Hurrah! A vignette on astrophysics, gravitational lensing, and physical confirmation of dark matter!!!

Keith Battye

I will look forward to them laying out how they are certain about the distances from us these phenomena are.
Who was the last guy to talk of drivel?

I read this a few days ago. I am sure they mapped something. I am sure something has caused the measurements they and others have made. Everything else is speculation. It is fun to speculate and play the what if I… game. At least the cosmologists are rational and sober (well maybe not) enough to take themselves no more seriously then the empirical measurements will.

Jim G

So, they have a map of where their fudge factor needs to be located to to explain, within standard accepted physics theology, their lack of understanding of the interaction between matter, energy and the resultant curvature of space (gravity). Sorry, I ain’t buying it…96% of the visible universe is “dark BS”. Think outside the box, guys, you’re missing something!!

Peter Melia

This question will, to the vast majority of your readers, be certain evidence of the questioners (my) lack of education, knowledge and etc. However, if some kind person could bear with me and answer my question, I would be grateful.
Question.
The current theory of the origin of the universe seems to state that after the big bang, matter streamed outwards from it’s origin and has continued accelerating ever since. Dark matter slows this acceleration down.
But our common experience is that any object we know of which is ejected violently from something else, by whatever means, will eventually lose speed and stop.
OK, this is because of environmental conditions around the ejected object.
We are told, and easily accept this, that if our object was ejected violently in a perfect vacuum, and free of gravity it would never slow down, it would just continue on at the same speed, forever.
How is it then that the particles ejected during the big bang, do not slow down, do not continue at the same speed forever, but actually accelerate. What is the accelerating force?

Bb

I agree. with Jim G.
it seems to me is a 96% of the universe is made up of mathematical particles and hyperdense equations.
These co(s)mic models remind me so much of global warming models.

Jim G

And, by the way, they did not “directly detect it” or “see it”, they inferred it based upon their theoretical “beliefs”. Check that subaru telescope for rust, my first one, car that is, rusted out quite rapidly.

Hans F.

Concerning the Dark Matter model I strongly recomend to read the new paper of P. Kroupa titled “The Dark Matter Crisis: Falsification of the Current Standard Model of Cosmology”, published in the Publications of the Astronomical Society of Australia.
Link: http://www.publish.csiro.au/paper/AS12005.htm
Direct link to the pdf: http://www.publish.csiro.au/?act=view_file&file_id=AS12005.pdf

Jim G.’s wake-up call should be taken seriously. Astronomer’s interpretations of gravitational lensing incorporate unquestioned assumptions. This is not really a direct detection; it may be just another example of confirmation bias. This report and even one hundred more “verifications” of cold dark matter may not stand up against an overwhelming falsification, which may come at any time in the future.

It sounds more like they’re describing electrical currents in plasma than magically invisible dark matter.

Gary Pearse

I wondered when someone was going to announce discovery of the imagined dark matter. I suspect there is a tautology at work here. Dark matter was postulated because gravity (as we know it) seemed too weak to account for the behaviour of spiral arms, etc. Shouldn’t we be re-evaluating what we “know” about gravity? I think the path to a unified theory is blocked by such fantasies as dark matter, but like Ptolemy with planetary motions in a geocentric universe, we will shoe-horn things to fit and even be able to make predictions with this painful cobbling.

Keith Battye says:
July 11, 2012 at 12:07 pm
I will look forward to them laying out how they are certain about the distances from us these phenomena are.
There are lots of places you can an explanation of that. Look around, and don’t pretend to be dumb. But the observation reported here does not depend on the distances being accurately known.

Keith Battye

I may have misunderstood the principles but I thought they were describing a 3 dimensional model, in which case the distances are surely important.

Meyer

Take a picture of two humans. One is sleeping, and the other is walking. The sleeping person is consistent with physical models, but the walking person exhibits unexplained motion of its appendages. I propose that the arms and legs are tugged by clumps of disembodied gravity surrounding the person.

meemoe_uk

Too right Jim G!
Trained in cosmology myself, the accepted cosmologyical model was all nonsense, nothing like science or physics. Just a load of very speculative maths theories, where if they broke, another fudge factor was chucked in, it was a routine. Then cosmologists would pat them selves on the back for another fudge factor ‘discovered’.
Today I’m really please to say I’m seeing the sad religion of dark matter and friends is losing substancial ground to other theories. The lectures on other theories are packing out theatres and are financially solvent enough to grow their own community.
It been great fun to follow it. The internet is an important media for these alternate ideas to prosper.
It turns out the establishment model has no right calling their model ‘ the standard model ‘ . It leaves out parts of the physics they don’t like.

Jim G says:
July 11, 2012 at 12:07 pm
Think outside the box, guys, you’re missing something!!
Dark Matter is thinking out of the box you seem to be in.

beng

Hold on, get ready for the kooks w/their pet theories….

polistra

Sheer nonsense. A term in an equation is not “matter”.
If they would give up on particles altogether and go back to de Broglie’s idea that everything is just waveforms, they might start making sense. Simplify, simplify, simplify.

mkelly

Will the Higgs boson make up dark matter? gravity and all. Maybe dark matter is only Higgs bosons.
We find the God particle and dark matter in the same week. Who’d a thunk it.

Meyer

I further propose that, by taking pictures of millions of walking humans and using motion blur or the Doppler effect to produce a map of the dark matter causing their anomalous movements, perhaps we can gain a better understanding of how these walking humans formed and predict where they will be located in the future.

James Evans

Good old Dark Matter. If observations don’t match the theory, throw away the observations.
The theory predicts that we should be able to see lots more stuff in our telescopes than we can. Therefore most of the stuff must be invisible. Jeenyus.

Keith Battye: a good introduction to this topic, and how they know with a fair degree of certainty how far away distant objects are, can be found in the book “A Universe from Nothing” by Lawrence Krauss. It’s available on the iBooks store, among other places.
Specifically – there is a direct relationship between the brightness of a certain kind of star called a Cephid, and the period of it’s oscillations. There’s a direct relationship between the brightness of a star and its distance from us (via the inverse square rule). Therefore, if you know the period of a Cephid star, and its brightness, you can work out with a fair amount of accuracy its distance from us. The distances were then later confirmed by using a different mechanism involving the relationship between the brightness and duration of supernova stars (about 3 supernova are observable somewhere in the sky on any given night). These tools give us an extremely accurate picture of the scale and distance of the Universe.
Furthermore, an examination of the spectra of these stars can show red or blue shifts, which can tell us with a high degree of accuracy at what speed distant objects are moving away or towards us. So we know that the Universe is expanding, how fast it has been expanding, and even that it is accelerating, not slowing down due to gravity.
The book is also a great introduction into why theories such as “dark matter” and “dark energy” are important because there simply isn’t enough visible matter and energy in the universe to explain its “flatness” and the acceleration of expansion that we are witnessing.

Keith Battye

Thank you for that information, it is greatly appreciated.
Having followed most of it I would still express some concern about the distances being stated as the assumptions seem to accumulate.

My gray matter rejects dark matter. Observation of light bending in the 1919 total eclipse was the first proof of Einsteins Relativity. For Universal models, i prefer the “Einsten-Godel Rotating Universe Model”…surpressed since 1949. The Cosmologists are not robbing us of big ‘alarm’ grants, but openess is lacking. See “Federally Funded Franken Science” on the possible reasons why…..part of a series including “The Cure for Cosmology’s Peptic Ulcer” and “Mysterious ‘Dr X’ says Universe is NOT Expanding”. [the post AGW science debate?]

A good tutorial on cosmology can be found here http://www.leif.org/EOS/Comology/cos01.pdf
There are 17 chapters. To see chapter nn use cosnn.pdf in the above link.
Many of your questions may answered there. Before shooting your mouth off, go check out the link(s), then pose questions to things you don’t understand.

howarth

I’m not a big believer in dark matter. When you have to event something out of thin air to explain an expanding universe you are really starting on the wrong end of discovery. And when you make a theory that states I will look into the universe until I find data that proves my theory you create an eventuality. The universe is big. Its really big. You look long enough your going to find absolutely anything you want. It becomes probable that you will find you own name written in gold with in a some yet unknown nebula. This isn’t science, its a money grab.

James Evans says:
July 11, 2012 at 1:12 pm
The theory predicts that we should be able to see lots more stuff in our telescopes than we can. Therefore most of the stuff must be invisible.
And that is spectacularly confirmed by the fact that we indeed cannot see it. We can, however, measure the gravitational effects from Dark Matter which shows it is there, just like in the 19th century we hadn’t seen the planet Neptune, but we knew it was there because of its gravitational effects on Uranus. We could even from those effects calculate where Neptune should be, and that is indeed where we found it. Such is the power of science.

beng says:
July 11, 2012 at 1:01 pm
Hold on, get ready for the kooks w/their pet theories….
They are already here, in farce.

A good tutorial on cosmology can be found here http://www.leif.org/EOS/Cosmology/cos01.pdf

Resourceguy

Is it warming or cooling and did we cause it?

Jim G

Leif Svalgaard says:
July 11, 2012 at 12:57 pm
Jim G says:
July 11, 2012 at 12:07 pm
Think outside the box, guys, you’re missing something!!
“Dark Matter is thinking out of the box you seem to be in.”
Like many of your responses, your gigantic ego is evident but not your logic. Dark matter is a fudge factor to fit with the existing most popular theory. I would not throw out the theory but find what is missing within it. Try not to be so nasty, you will be much happier in the long run.

Peter Melia says:
July 11, 2012 at 12:18 pm
Question.
The current theory of the origin of the universe seems to state that after the big bang, matter streamed outwards from its origin

No, matter stayed where it was, it is space itself [what is between particles of matter] that is expanding. Matter does not stream away from anything.

G. Karst

This is very similar to the Higgs Boson announcement. They have illuminated an anomaly where they expected, but have not identified the actual anomaly. Too early for parades, but it is exciting. GK

JCWToronto

Dark Matter; Terra Incognita: only the names change.

wikeroy

Did they find Darth Vader too?

Elftone

Fascinating stuff, with a few problems:
Scientists have, for the first time, directly detected part of the invisible dark matter skeleton of the universe, where more than half of all matter is believed to reside.
Indirectly. They say, “Dark matter, whose composition is still a mystery, doesn’t emit or absorb light, so astronomers can’t see it directly with telescopes. They deduce that it exists based on how its gravity affects visible matter”. I believe this should say “radiation” as opposed to just “light”, but the point is moot – dark matter, as theorised, is unobservable directly. Only its effects can be measured.
“We found the dark matter filaments. For the first time, we can see them,” said Jörg Dietrich
They may or may not have found dark matter filaments, but they have not been “seen”. This does not detract from their work or their abilities, but it is inaccurate reporting, and does them no favours in a time when every phrase is instantly scrutinised for accuracy and meaning. It would be a shame for good, honest work to be demeaned because of this.

Leif,
Would you kindly repost the file? I get
404 Error File Not Found
The page you are looking for might have been removed,
had its name changed, or is temporarily unavailable.

John Silver

More modeling madness

G. Karst

cknlitl says:
July 11, 2012 at 2:14 pm
Leif,
Would you kindly repost the file? I get
404 Error File Not Found

Lief mozilla reports same altho there is nothing wrong with the address.
I was able to navigate from here:
http://www.leif.org/EOS/Cosmology/
GK

Jim G

Leif Svalgaard says:
July 11, 2012 at 1:48 pm
Peter Melia says:
July 11, 2012 at 12:18 pm
Question.
The current theory of the origin of the universe seems to state that after the big bang, matter streamed outwards from its origin
“No, matter stayed where it was, it is space itself [what is between particles of matter] that is expanding. Matter does not stream away from anything”
No Leif, it is more probable that both were occuring, space was expanding and the matter within it was moving in whatever direction was dictated by gravity or the energy imparted to it by the initial conditions of the “Big Bang”. Some theories say this was the explosion of a singularity and some the collision of another “multiverse” with ours. In either case, since I was not there at the time I will only say “probable”. If you were there, let me know.

MotorMouth

Wow! Are there really sheeple like this? Scientists use far more accurate methods to determine these things than those upon which we all rely. I’m assuming these guys don’t believe X-Rays, UV or infra-red is real, either. Observing gravitational lensing is no different to observing diffraction through water. Healthy scepticism is one thing but this level of ignorance is quite confronting.

I’m frankly alarmed at the level of unscientific thinking being demonstrated here. Leif is perfectly correct when he says you should read up on this subject before commenting on it further. You are only exposing your ignorance of the issues involved. Cosmology and Quantum mechanics are bastions of hard headed, fact and evidence based science where there is a healthy community of skeptical thinking and experimentation, and wholesale throwing out of theories that no longer fit. I can’t of any other scientific fields which are more ready to destroy all of their theoretical underpinnings on the basis of experimental observation. And both fields are full of competing theories, where experimental evidence is sought and demanded to prove or disprove them.
Please don’t apply your well deserved disdain for Climate Science to Cosmology or Particle Physics. At least in Cosmology they test their theories, and modify them to fit new observational evidence.

dp

It would be interesting to learn this is a Lagrangian point between galactic clusters and that there’s really nothing there but gravity.

Gary Hladik

James Hastings-Trew says (July 11, 2012 at 2:40 pm): “Please don’t apply your well deserved disdain for Climate Science to Cosmology or Particle Physics. At least in Cosmology they test their theories, and modify them to fit new observational evidence.”
When one branch of science becomes untrustworthy, it inevitably tarnishes the reputation of all science. Cosmology and particle physics are especially vulnerable because they’re so complex and just so…bizarre…compared with our ordinary experience.

Crito

Perhaps the universe is only a failed experiment by an imperfect demigod and the reason it is so hard to figure out is because that demigod had no idea what they were doing. No plan at all.

If I remember correctly, the universe’s missing matter turns out to be all the packaging that the instruments, bought by scientists to detect missing matter, were wrapped in, which they had thrown away – according the that infallible work ‘The Hitchhiker’s Guide to the Galaxy’ anyway.

Elftone

James Hastings-Trew says:
July 11, 2012 at 2:40 pm
…Please don’t apply your well deserved disdain for Climate Science to Cosmology or Particle Physics. At least in Cosmology they test their theories, and modify them to fit new observational evidence.

Hear, hear!

Jim G

There are many other issues that have been brought up by reputable scientists that obviate the need for the dark matter and/or dark energy factors and/or elliminate some of the problems of combining quantum physics with general relativity including: separation of space/time into space and time, the potential for the speed of light to have been different under the initial conditions of the new born universe, the possible (probable?) quantum nature of space itself with discrete quantae of space, different energy levels at a given time and place, location and/or size factors which might cause the rules to change. Just as at one level Newtonian physics was a good predictor of what one might see through a telescope but general relativity was better and more accurate. Guys like João Magueijo and Steven Hawking and Petr Hořava and many others are not kooks and have discussed these issues and written about them and are thinking outside the box. Inside the box people accept what is most popular.

Not to panic, dark evil forces of our universe Dark Matter and Dark Energy are kept at a distance from our precious galaxy by the good guys, baryonic fighters known as MACHOs reflecting their superior potency.

Jim G

James Hastings-Trew says:
July 11, 2012 at 2:40 pm
“I’m frankly alarmed at the level of unscientific thinking being demonstrated here. Leif is perfectly correct when he says you should read up on this subject before commenting on it further.”
Advising others to read up on a subject because they disagree with you when you do not have any idea what their educational background is or what they may have read is, in itself, remarkably
condescending and evidence of poor judgement.

u.k. (us)

“The gravity of massive objects such as galaxy clusters acts as a lens to bend and distort the light from more distant objects as it passes.”……..
==========
So, if the light passes just the right way around these lens/clusters, we could see the light emitted by our galaxy 2 billion years ago ?
You know, like using a planets gravity to induce the trajectory for our deep space satellites.
The right trajectory would send a satellite right back at us.
Light is different ?