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Hubble Space Telescope Detects Ring of Dark Matter
mknewman wrote with a link to a story on the NASA site indicating that they may have finally found dark matter using the Hubble telescope. We've discussed the stuff a few times in the last year, with the Hubble actually mapping out the dark matter in the universe in January. This, though, may be our first 'sighting' of the elusive substance. "NASA will hold a media teleconference at 1 p.m. EDT on May 15 to discuss the strongest evidence to date that dark matter exists. This evidence was found in a ghostly ring of dark matter in the cluster CL0024+17, discovered using NASA's Hubble Space Telescope. The ring is the first detection of dark matter with a unique structure different from the distribution of both the galaxies and the hot gas in the cluster. The discovery will be featured in the June 20 issue of the Astrophysical Journal."
I heard it circles Uranus.
except, of course, all the astrophysicists who often pointed out that exactly this kind of discovery was just around the corner.
How we know is more important than what we know.
Wow - I am impressed that they managed to provide so little information about such a momentous event!
I for one will be counting down the minutes until their press conference and the availability of any actual information about their discovery.
Screenshot or it didn't happen!
What, no Klingon jokes yet?
Welcome to the Panopticon. Used to be a prison, now it's your home.
Redmond Washington.
Ok, mod me as troll. I deserve it.
---- Teach Peace. It's Cheaper Than War.
Is it just me, or are humans getting better and better at science as time progresses?
I mean, it seems likely that this would be the case, naturally. Nonetheless, it still strikes me.
We predict dark matter exists, then we show it exists. It seems pretty much assured that we will even find out what it is made of. This discovery further cements this feeling in my mind.
We figure there is a chemical of inheritance, we find DNA. We know there is a genome, we sequence it.
Everything seems to be a big puzzle, and we seem to be getting faster and more accurate with putting these puzzles together.
I feel fully confident in speculating, for instance, that we will solve the gene therapy issues in mere years. That we will have household humanoid robots by 2020 for under $50,000US. That we will enhance ourselves dramatically genetically and technologically by the end of the century.
Has science always been this inexorable in it's progress?
Read my Very Short "Stories"
Later they find out it's just waste dropped by alien spacecraft.
"Please, shut up. Just when I think you can't say anything more stupid, you speak again." -Archie Bunker.
Dude, I sure hope Paul sees this. You zinged him!
I was about to write a comment panning this submission, because apparantly a one-paragraph press release - that doesn't give much room for an intelligent discussion - was the only information on this discovery. But I did find an abstract for a talk given at the American Astronomical Society Meeting 209, which was held in January this year.
Unfortunately I can't find the paper itself. So there is slightly more info, but not much :-(
The photino birds are coming for us!
http://en.wikipedia.org/wiki/Ring_(novel)
It could happen. But if we piss off those robots and the genetically engineered humans, they may band together and start an extermination program of us humans. Then we'd have to flee the planet in a fleet of ships while the robots pursue us. Of course, with the genetically engineered humans, they'll look like us and they'd be used as spies. Of course, there may be a comuter scientist who falls in love with one of them and helps the robots take us out. Then he'll go insane and start imagining his robot lover.
I don't know if we really want to go there.
I prefer Flambe as apposed flamebait.
There's a 1% chance that I might have found that funny if you'd found a way to spell Uranus that actually contained the 4-letter word that's supposed to be the source of the humor.
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
Given that the press conference isn't until May 15, I can't say for sure, but based on the brief blurb on the NASA website, it's almost certainly a gravitational lensing measurement.
It's true that dark matter doesn't interact directly with light, but it does curve space (ie. generate gravity), which light travels through. So light feels the gravitational effect of dark matter, a phenomenon known as "gravitational lensing". Essentially, the images of background galaxies going through a concentration of dark matter become magnified and distorted.
I don't know whether this is a strong lensing or weak lensing measurement. In strong lensing, the distortion is extreme and the images of the background get stretched into long tangential (and radial, though they're rarer) arcs like this. In the case of weak lensing, the distortion in any one image is small, but all images in a certain area are distorted coherently so you can statistically disentangle the signal.
Given the distorted images of the background galaxies, you can determine what mass distribution was responsible for those distortions, thereby producing a "mass map". It appears that in this case (again, based on the brief blurb), the mass map shows some sort of ring-like structure that isn't seen at any other wavelength (which non-dark matter would produce).
[TMB]
They really need to change the name of that planet, to get rid of that stupid joke once and for all.
Why does the title read "Hubble Space Telescope Detects Ring of Dark Matter" when - as the first line of the summary states -, the HST actually only " may have finally found dark matter".
"Has found" and "may have found" are very different things. I "may have" the lotto ticket which is going to win me millions of dollars in Saturday's draw; on the other hand, I may not. To pre-emptively state a conclusion before it has been made is foolish and extremely unscientific and simply not an accurate description.
Not all scientific predictions are made equal.
The Raven
... to be too excited about this? I mean, scientists characterizes the behavior and name the thingie 'dark matter'. So even when they can conclusively say this ring-thing is made of such and such, but who knows how many type of 'dark matter' there really are.
...last year: astronomers could see in the aftermath of two colliding galactic clusters.
The visible matter's momentum through space was impeded at quite a different rate than dark matter. This left four distinct zones of gravitational lensing, but only TWO were associated with visible matter. The other two were dark matter halos that had been separated from each galactic cluster.
KANG: De-lak DOH! Bosh-ta-jah Uranus!
KODOS: jIyajbe'! Uranus-ghor tlhInganpu' tagh'a'?
KANG: yIDoghQo'!
(My Klingonese is better than most people's Swahili...)
---GEC
I'm but the humble pupil, seeking to snatch the scratchbuilt pebble from the master's fully articulated hand
"It seems dark-matter is nature's sex drug. It's like a perverted trail mix of penguin estrogen, penguine Viagra and Spanish penguin fly." - Paul, the space hippy
... and then they built the supercollider.
There's a string of overhyped submissions here in the science section founded on a misreading of the source article.
Contrary to what the submission seems imply, the Hubble did not directly detect dark matter, and you can pretty safely bet that it won't ever.
What it did was find further evidence that dark matter exists. I don't think these media teleconferences are very rare, but they don't hold them every time somebody publishes a paper, either.
My reading of the press conference announcement is that the shape and motion of the galactic cluster in question is not possible based soley on visible mass. Furthermore, I suspect they will contend that assymmetry in their observations rules out with some degree of certainty an explanation of the observations using Modified Newtonian Dynamics (MOND), because such a finding would lead to the suspiscion that the dark matter is distributed differently from the galaxies and hot dust in the cluster (mentioned in the release). Currently MOND is the leading alternative theory to dark matter for explaining the galactic rotation curves, but it generally implies the dark matter effect should be distributed in the same fashion as normal matter.
It is the nature of the scientific method that contradicting one theory is further support for any unaffected competing theories. I think that's what is happening here. I don't think the legs are being kicked completely out from under MOND, but I'd bet it will be walking a little wobbly after this.
They should call it Goatse.
After his observations in the 1930's Zwicky argued that clusters of galaxies had enormous amounts of this stuff "dark matter". Then in 1970's Vera Rubin published studies showing that stars and dust orbited there galaxy orbited faster than they should be. This was a violation of Newton's and Kepler's laws. The only way to explain this was "dark matter". What "dark matter" is made up of is not known. Some theories are that is comprised of non-baryonic matter(exotic particles such as neutrinos) or baryonic matter(gas, dust, Jupiter size objects). The reason it is called "dark matter" is because whatever it is it gives off no detectable light. We can only infer its existence by how it acts on the environment around it. The speed of galaxies orbiting each other in cluster, gas dust and starts orbital speed around there centers and a phenomena called gravitational lensing.
The book is only boring becuase Diamond makes his basic point in the first chapter, and then repeats the same damn point as the explanation for every cultural disparity that he cites as distinguishing between people from ancestral central Eurasia and, for example, ancestral Mexico.
I'll ruin it for you: the point is that there were significantly more square miles of easily travelled arable land in the same climate zone accessible to people on the eurasian landmass than there was available to the Incas and Mayans. Since there was more land in eurasia, the people there had a wider variety of high-protein foods, which allowed for more leisure time to develop technologies. They also just happened to have more high-protein crops and easily domesticable animals like horses, cows, sheep, and goats. So all of these facts worked together to give southern europeans/north africans an insurmountable advantage in nutrition, which led to more leisure time, which led to better technology, which led to better nutrition, which led to more leisure time... lather, rinse, repeat.
And that's why Spain conquered Mexico and not the other way around.
Humpty Dumpty was pushed.
Many news groups are filled with those that "believe" they are scientific, but don't actually follow the scientific method. Slashdot is no exception when it comes to pseudoscience.
Examples:
1) Those that believe Star Trek is science-fiction, and not fantasy in space.
2) Those that believe Global Warming because they personally experienced a hot day or observed an inconvienint movie, instead of comparing Earth climate history with current solar trends.
3) Those that believe I should be modded down for not parroting some political party line or pre-decided conclusion, instead of modded up for reccommending that we require observable evidence and logical reasoning in order to prosper.
The Slashdot FAQ should suggest moderating down the stupid, instead of all others that aren't blind followers of one's own faith. (operating system, political party, pseudoscience) I suspect many flame-wars could be avoided this way.
The discovery has been retracted after discovering the telescope was accidentally aimed at the earth and the persons behind that it was aimed at moved.
$50,000 will buy you ONE chocolate-flavored corn syrup bar; unless you pay with Ameros then its only $5.
Democracy Now! - uncensored, anti-establishment news
I had been under the impression that 'dark' matter was simply regular matter that we needed to exist to balance some equations, but that we couldn't see. Wouldn't this simply reduce the amount of dark matter by making it observable?
Or is my impression that dark matter is stuff we can't see wrong? Is it actually supposed to be some exotic substance (with comic-book like powers)?
More Caffeine. NOW
No pic needed, please see the story above this one.
It seems that what the Hubble found was Jimmy Doohan's ashes circling around in space.
Where they belong, i might add.
Huh?
... there's damned little you can do with Hubble (other than observe in the ultraviolet, and honestly, when was the last time you heard about that capability leading to some huge discovery?) that you can't do with a reasonably large terrestrial scope.
Hubble is, by today's terrestrial standards, small. Its resolving power is limited, even in the relative vacuum of space, by the size of its mirror, the size, age and design of its instruments, and so on.
Yes, Hubble finds stuff. But it doesn't find disproportionately more stuff than 8-10 meter terrestrial scopes like Gemini, Subaru, or Keck.
Do the astrophysicists want it? Hell yeah - sure, big scopes on the ground can deliver results as good as Hubble's, but there aren't a lot of those to go around, and there's a limited amount of darkness, good weather, etc. So having Hubble in the mix means more research can get done, simply because there's another good tool available.
Just a thought.
Village idiot in some extremely smart villages.
We have energy. We have dark energy.
Where's the anti-energy? And why isn't there anti-dark matter? Or anti-dark energy for that matter (pun intended)?
-Clio
Karma: Bad (mostly from not giving a fuck)
Blog: http://clintjcl.wordpress.com
I will call it Myass
With all the jokes on this thread, I'm wondering: Is humor relative, or is it a quantum phenomenon?
In other news, astrophysicists have announced that they now know what all that dark matter is: it's stupidity.
Many will not be able to tell them apart.
This issue is a bit more complicated than you think.
Last August, an announcement was made about the discovery of dark matter using gravitational lensing, based on CHANDRA observations.
This past January, a map of dark matter was created using millions objects in the night sky as a result of a massive collaboration effort known as COSMOS. The 3d dark matter map of a 2 degree section of the sky matches predictions of the evolution of dark matter.
So, what exactly does mknewman mean by, "may have finally found dark matter"? What rock have you been hiding under for the past year? (Not that the rest of slashdot is caught up, given comments random people make whenever dark matter shows up in an article)
Hmmmm....
The fact of the matter is, that doesn't look like dark matter to me, more like white matter.
Oh well, it doesn't matter...
Why, yes! I AM new here.
TWW
"Encyclopedia" is to "Wikipedia" what "Library" is to "Some people at a bus stop"
It really depends on what you consider progress, and in what timeframes you're looking.
During the 1650-1700 period a LOT of 'new science' was thought out, by such people as Newton, Leibniz, Spinoza, Huygens. Not all of it well grounded, not all of it useful, but that was a time where a lot of new thoughts were 'floating around' and being proven and disproven on an almost daily basis. These were people that set out to 'know everything' and in the process ended up creating a base that a lot of modern science still uses. Back then you only needed a rich patron to spend the rest of your life doing research. Nowadays, you're going to need corporate or governmental backing (either in academics or not) to get most things done.
In comparison the 8 centuries before that, pretty much nothing of note happened for a long long time. It also very much depends (as someone else mentioned as well) on the social and political environment of the time.
But if you're thinking that science nowadays is progressing, I can't totally agree. In certain fields it is, but other fields for example are totally stagnant, once again mostly due to politosocial environment issues.
NASA is hardly doing to amount of discoveries they're capable of, due to simple lack of funding. The same goes for a lot of 'fusion' projects, for example. Mainly it's a limitation of technology vs cost. To expand on things now, the costs are so high as to sometimes be completely prohibitive.
A shame really..
Coz eternity my friend, is a long *ing time.
Err. No. We did *not* predict dark matter. We were not expecting dark matter or anything like it when the Zwicky first saw that there had to be some "more" matter in the galaxies to explain the observed rotational curves. He probably first said: "Gee, well, that looks funny!" Zwicky probably said something a lot better actually, as he was known for his, often rude, mannerisms.
The astonishing discoveries in science come when humans really have no clue what is coming next! Case in point: The November Revolution in Physics . That was the last time that the whole paradigm of understanding of particle physics shifted! That was back in 1974 and hasn't changed since! One new totally-unexpected particle, called the J/psi, was found and boom... the consequences were huge, for now, you *knew* that there had to more particles, namely the top and the bottom and that the W and the Z were predicted as well. Only after the discovery of all these predicted particles did the public came to accept the Standard Model and particle physics became a mature field. But, back in 1974, there were those who could see ahead in the light of this new discovery.
A large shift in the understanding of the universe happened already in astrophysics with the CMB(Cosmic Microwave Background) measurements. I liken it very much to the November Revolution. The CMB observations, first from COBE and later from WMAP and various other ground based observations, show with high statistics that there is something missing if we assume that the universe is all baryonic matter. Imagine a puzzle where there is a missing piece and now, you think of a piece that fits in this place. Well, dark matter fits the bill very well and other observations, also back it up. So somehow, dark matter is required by experimental results... Now, those who can see ahead make predictions on what we will --hopefully -- discover next: a dark matter candidate particle at the LHC, annihilation products of dark matter in space, a signal in gamma rays from annihilation, plenty of lensing examples in galaxies,.. This is called phenomenology for a reason. You get an idea inspired by experimental results from an experiment and look at what other phenomena you would observe in the light of your idea/theory.
End of my rant.
To put your "inexorableness" theory in perspective. There are more humans living on the planet right now, then has ever lived in total in the history of earth. So take humans and divide them into two groups: Group1: from the beginning of human evolution to 1920 and Group2: from 1920 to today. Group2 is significantly larger in population. Do you think Group2 achieved more? Really?!! I dont think so! I see most of the population watching TV and going to work where they try to minimize thinking! Group1 had to struggle more for survival and had to be more inventive to survive. The pressure is off on Group2. Laziness is settling in fast.
I, for one, welcomes our new Overlords of Dark Ring.
Eclipse PDE and Me
Additional information will be released at an upcoming DASA teleconference.
That link is interesting, but baked right into their assumptions is the existence of Dark Matter. They assume the mass ratio of plasma to solid stuff is high. This is probably based on the assumption that Dark Matter holds a normal galaxy together. Every time I've read about why dark matter is required to hold a galaxy together, it comes down to the galactic rotation curve "problem". I've said it many times before, using Keplers laws to say what the rotation curve should be is invalid, yet that's what may people do. Including Wikipedia! If one models a galaxy as a uniform disk of point masses, you get an expected rotation curve quite different from that - even increasing towards the edge. The obvious discrepancy in the later case is that galaxies have a non-uniform mass distribution (big surprise huh). The bottom line is that we must not use a 2-body gravitational model for a system with millions (or billions) of bodies. OTOH if some jackass hadn't made this mistake we wouldn't have had all these exciting stories about Dark Matter for the last how many years....
Philip Pullman? Is that you?
How can a post be modded "overrated" or "underrated" when it hasn't been rated yet?
Yawn
"Dark matter" is actually just molecular hydrogen, which isn't easily detected and is in proportion more common than atomic hydrogen in quantities that exactly or almost exactly match the "missing mass" that "dark matter" solves without the need for exotic matter/energy. The simplest answer is usually the correct one.
"except, of course, all the astrophysicists who often pointed out that exactly this kind of discovery was just around the corner."
Now live with it!
Here is another article on the subject.
What does lightning look like when it comes close to hitting you? It looks like a point.
The dark matter looks like a ring in 2D. That means it's coming this way.
What's coming? Well, what do we know that is big and dark?
Borg ships. A horde no less.