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Mysterious Dark Matter Blob Confounds Experts

Soulskill posted more than 2 years ago | from the dark-matter-needs-vacations-too dept.

Space 151

mayberry42 writes "Astronomers using the Hubble Space Telescope are mystified by a merging galaxy cluster known as Abell 520 in which concentrations of visible matter and dark matter have apparently come unglued. A report on the Hubble observations, published in the Astrophysical Journal, raises more questions than answers about a cosmic pile-up that's occurring 2.4 billion light-years away. 'According to our current theory,' says Arif Babul, the study team's senior theorist, 'galaxies and dark matter are expected to stay together, even through a collision. But that's not what's happening in Abell 520. Here, the dark matter appears to have pooled to form the dark core, but most of the associated galaxies seem to have moved on.'"

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Observed Dark Matter? (0)

Anonymous Coward | more than 2 years ago | (#39234529)

What the heck? I thought part of the definition is that we can *not* directly observe Dark Matter?

Re:Observed Dark Matter? (4, Insightful)

Tablizer (95088) | more than 2 years ago | (#39234553)

We can't directly observe air either (in most cases), but can still measure its effects.

Jacksprat Nechum (-1, Offtopic)

Anonymous Coward | more than 2 years ago | (#39234815)

Louis Capet himself had given it to him; and you might have had the life of the little gentleman, but not this cane with the tiny golden bust of his unhappy monarch.
He say, 'Hengland, she is mine--trejous.
General rules can be suggested, but the best results can be obtained only by following such methods as experience and practice show to be the best suited to the specific conditions.

Its simple (2)

fyngyrz (762201) | more than 2 years ago | (#39234905)

Here, the dark matter appears to have pooled to form the dark core, but most of the associated galaxies seem to have moved on.

When we get to look more closely, we'll see it's a convention of elephants and tortoises.

Re:Its simple (2, Funny)

rust627 (1072296) | more than 2 years ago | (#39235641)

four elephants, standing on the back of a great space turtle ........

Re:Observed Dark Matter? (1)

Smauler (915644) | more than 2 years ago | (#39235349)

We can't directly observe air either (in most cases), but can still measure its effects.

What? Seriously, what?

The human body has plenty of senses, a lot of which detect air directly. Touch would be the first simple example. To be honest, I'm having a hard time thinking of a sense that doesn't experience air - all would be affected..

Re:Observed Dark Matter? (1)

ThePeices (635180) | more than 2 years ago | (#39235625)

Hi there,

You seem to have missed reading the word 'observed' in your reply to the poster above. You cannot see air, you cannot see dark matter. Directly. (dark matter does not interact with matter via the Electromagnetic Force). But through measuring its other effects on matter, we can infer its existence. Kind of like air. (please note the use of the word 'kind' in the previous sentence)

The poster above was making the point that we cannot see air through the visible spectrum that our eyes detect. He made this point to show the similarity to how we can detect ( but cannot see ), dark matter.

That is the reason you could not make sense of his post. Now that the word 'observed' has been pointed out to you, everything will now become clear to you.

Re:Observed Dark Matter? (-1, Flamebait)

datavirtue (1104259) | more than 2 years ago | (#39236011)

blah blah blah blah blah ....you're full of shit

Re:Observed Dark Matter? (-1)

Anonymous Coward | more than 2 years ago | (#39236023)

Yeah, we've never observed refraction of light into air. Ignoramus.

Re:Observed Dark Matter? (1)

Anonymous Coward | more than 2 years ago | (#39237157)

observing refraction of light into air != observing air.

Re:Observed Dark Matter? (1)

robbiedo (553308) | more than 2 years ago | (#39237861)

Apparently, you never lived in Los Angeles.

Re:Observed Dark Matter? (3, Insightful)

JoshuaZ (1134087) | more than 2 years ago | (#39234595)

We can't. What we can observe is the gravitational pull of dark matter (which is the entire reason we know it is there). In this case, they can see where the dark matter is because of its gravitational effects.

Re:Observed Dark Matter? (1)

muecksteiner (102093) | more than 2 years ago | (#39234639)

Right, except that we are talking about fairly static images of (for all practical purposes, randomly placed) stars and galaxies billions of light years away. How exactly does one figure out gravitational effects between the stars and galaxies in such an image?

Re:Observed Dark Matter? (0)

Anonymous Coward | more than 2 years ago | (#39234669)

By studying light distortion (gravitational lenses effect).

Re:Observed Dark Matter? (5, Informative)

Ruie (30480) | more than 2 years ago | (#39234679)

One way to figure out gravitational field from a static image is to look at galaxy distribution behind the gravitational field. If it is squishes space in one direction while stretching it in the other, you will see more galaxies longer in one direction then in the other, so you can build a map of distortion and compute gravitational field from it. The result will be coarse, but you will see large concentrations of matter.

Re:Observed Dark Matter? (2)

PopeRatzo (965947) | more than 2 years ago | (#39235085)

Seriously? That's how they do it?

That is so cool. Is this something that would be detectible by a person looking at one of these images or is the effect too subtle? I'd love to look at some of those images, if it was an effect I could see.

Do you think any of these images are available? I tried googling but none of the combinations of terms gave me anything I could look at.

Re:Observed Dark Matter? (5, Informative)

JoshuaZ (1134087) | more than 2 years ago | (#39234687)

They detected it by gravitational lensing. http://en.wikipedia.org/wiki/Gravitational_lens [wikipedia.org] . The dark matter is massive enough that it bends the light passing through it. So you can for example see that a star looks bent and not as spherical if it is behind a lot of dark matter. In the really blatant examples of gravitational lensing you get things like the Einstein Cross http://en.wikipedia.org/wiki/Einstein_Cross [wikipedia.org] where you can see multiple copies of the same object.

Re:Observed Dark Matter? (-1, Flamebait)

datavirtue (1104259) | more than 2 years ago | (#39236037)

I'm so tired of these boring lame ass explainations for the cosmos. Just say: I DON'T KNOW for fuck's sake.

Re:Observed Dark Matter? (0)

Anonymous Coward | more than 2 years ago | (#39236565)

I'm so tired of these boring lame ass explainations for the cosmos. Just say: I DON'T KNOW for fuck's sake.

just because _you_ don't know doesn't mean nobody does.

Re:Observed Dark Matter? (1)

maxwell demon (590494) | more than 2 years ago | (#39238001)

If people had done that throughout history, our current understanding of the world would not be much different from that in the stone age. You'd have no computer and no internet, no electricity, no steam engine, not even windmills. Every advance in human knowledge comes from looking for explanations. Some explanations later turn out to be wrong, those are then thrown away. Other explanations turn out to stand the test of time. The latter make up our knowledge about the universe.

Re:Observed Dark Matter? (2)

History's Coming To (1059484) | more than 2 years ago | (#39234765)

In some cases the red shift can give you velocity information from a "snapshot", nature's good with compression algorithms ;)
Not sure if there's enough variation in this case to make it particularly useful, I'll probably have to read the fine article.

Re:Observed Dark Matter? (0)

Anonymous Coward | more than 2 years ago | (#39234673)

So if I have a blue balloon, is it because of the gravitational affect on helium?
This could also explain a certain condition that afflicts males.

Re:Observed Dark Matter? (-1, Troll)

datavirtue (1104259) | more than 2 years ago | (#39236025)

blah blah blah blah...parrot squawks....you are full of dung....when we can pwn gravity I will listen to the ramblings of ignorant assholes

Re:Observed Dark Matter? (2)

KingBenny (1301797) | more than 2 years ago | (#39234653)

maybe it's just those rogue neutrino's acting pranks again

Re:Observed Dark Matter? (-1, Troll)

datavirtue (1104259) | more than 2 years ago | (#39235989)

It is obvious that we are toddlers when it comes to understanding cosmic forces. When we can manipulate gravity to our will I will then listen to what these crackpots theorize about black holes, dark matter, and generally any other phenomena we can't OBSERVE.

Re:Observed Dark Matter? (1)

Man Eating Duck (534479) | more than 2 years ago | (#39237477)

It is obvious that we are toddlers when it comes to understanding cosmic forces. When we can manipulate gravity to our will I will then listen to what these crackpots theorize about black holes, dark matter, and generally any other phenomena we can't OBSERVE.

Probably feeding a troll here, but... seriously, what the fuck are you going on about? Sure, you just lean back and wait until we can "manipulate gravity to our will" (don't hold your breath), meanwhile the rest of us will continue trying to figure this out. Mind you, "figuring this out" is a likely prerequisite for your goal.

Re:Observed Dark Matter? roxy (0)

Anonymous Coward | more than 2 years ago | (#39236605)

We have observed dark matter. The moon is dark matter, the asteroids are dark matter, etc. The galaxies are filled with all sorts of rocky trash and dead stars. We can barely see the asteroids in our own solar system with telescopes, do you really think we can observe in any way the rocks zillions of miles away in other galaxies????
Think about it.

Re:Observed Dark Matter? roxy (5, Insightful)

hughJ (1343331) | more than 2 years ago | (#39237517)

"Dark matter" isn't simply regular matter/particles that we just can't see due to not emitting light. We may not know quite what it is, but we have a pretty good idea about what it is not, and that's regular matter as we know it.

"...occurring 2.4 billion light-years away." (0, Redundant)

Anonymous Coward | more than 2 years ago | (#39234547)

WTF?

Re:"...occurring 2.4 billion light-years away." (0)

Anonymous Coward | more than 2 years ago | (#39234641)

Old news. This happened when your ancestors were so amazingly primitive, they still thought nuclei were a pretty neat idea.

Mysterious Dark Matter Blob Confounds Experts (4, Funny)

busyqth (2566075) | more than 2 years ago | (#39234555)

I'm pretty sure this headline is about my recent visit from the plumber.

The Bridge (0, Offtopic)

Flipstylee (1932884) | more than 2 years ago | (#39234559)

Has anyone seen that confounded bridge?

Also, FIRST!

Move on (5, Funny)

oldhack (1037484) | more than 2 years ago | (#39234575)

The galaxies are gone. Horse has already left the barn. Spilled milk. Water under the bridge.

Dark matter needs to buck up, get it together, and move on, get on with the life. There is a whole universe out there.

Re:Move on (0)

PolygamousRanchKid (1290638) | more than 2 years ago | (#39234921)

Dark matter needs to buck up, get it together, and move on, get on with the life.

Maybe it's some kind of Dark Matter "Occupy Galaxy", or something . . . ?

Re:Move on (1)

snowgirl (978879) | more than 2 years ago | (#39235257)

The galaxies are gone. Horse has already left the barn. Spilled milk. Water under the bridge.

No shit... best estimates are that this happened 2.4 billion years ago, so... yeah, grow up dark matter...

Re:Move on (1)

Vaphell (1489021) | more than 2 years ago | (#39237159)

imo you can't really say 2.4 billion years ago. That would make sense only if there was one universal time scale with the necessary requirement of information being broadcasted instantaneously. Considering that it's not possible (hard cap of c), every point has its own time and events happen when information about them, spreading at the speed of light reaches said point. For us on Earth that dark matter stuff is happening right now.

Re:Move on (2)

snowgirl (978879) | more than 2 years ago | (#39237469)

imo you can't really say 2.4 billion years ago. That would make sense only if there was one universal time scale with the necessary requirement of information being broadcasted instantaneously. Considering that it's not possible (hard cap of c), every point has its own time and events happen when information about them, spreading at the speed of light reaches said point. For us on Earth that dark matter stuff is happening right now.

Yeah, well, you're just speaking within your reference frame. In my reference frame, I'm located at a point equidistant in space and time from both this event, and you, and I see you responding to this event 2.4 billion years late...

Of course I won't actually see the light from you responding to this post until at the earliest 1.2 billion years from now... but since I can violate causality with my tachyon emissions, I've already witnessed your observation, and response, and responded myself....

All that aside, I was going to post that it happened "2.4 billions years away!" but I was afraid no one would get the joke...

Re:Move on (1)

datavirtue (1104259) | more than 2 years ago | (#39236043)

The asgard chuckle....

U are my heart, my Universe! (-1)

Anonymous Coward | more than 2 years ago | (#39234605)

[Todd Chester stares in horror at Eddie draining the RV toilet]
Eddie: Merry Christmas. Shitter was full.

From my understanding... (5, Interesting)

Zakabog (603757) | more than 2 years ago | (#39234635)

From my understanding of dark matter, isn't it likely yhat they're looking at two entirely different types of matter? I thought dark matter was just matter that we can't "see" but can detect due to it's gravitational effect on visible light. So why would it be so far fetched to think there's more than one type of matter in the universe that we can't currently directly observe?

Re:From my understanding... (2, Funny)

Dunbal (464142) | more than 2 years ago | (#39234779)

isn't it likely yhat they're looking at two entirely different types of matter?

Yup, typical response from physicists for oh I dunno almost the past 100 years. Can't explain something? Must be a new particle...

Re:From my understanding... (1)

Anonymous Coward | more than 2 years ago | (#39235081)

You say that like it's a bad thing. Or a wrong thing. There's a lot of people who seem to think that Science is something for settling very large issues, so that when it is wrong, it is very very wrong: believing that red things are actually green, or something like that. This is almost never the case: Science is the search for the least wrong understanding of the universe, and for the most part we understand the universe well. In this case, the alternative theories suck. In particle physics, we have scientists spending years to confirm whether particles actually exist. What is your basis to contradict that?

to GP, dark matter is yes, a fundamentally different type of matter, in theory. It is expected to be non-baryonic, that is, not made of quarks (electrons are also composed of different particles). Is it a law that the people who are most skeptical are the most ignorant, or just a six sigma correlation?

Re:From my understanding... (-1, Flamebait)

datavirtue (1104259) | more than 2 years ago | (#39236059)

We understand the universe well? Gravity anyone? You make me sick. We understand what our pathetic sensors (eyes) perceive. What a joke.

Re:From my understanding... (1)

maxwell demon (590494) | more than 2 years ago | (#39237897)

(electrons are also composed of different particles)

According to our current understanding, electrons are not assembled at all.

Re:From my understanding... (1)

Livius (318358) | more than 2 years ago | (#39235405)

No, you're thinking of the scriptwriters of Star Trek Voyager.

Re:From my understanding... (1)

osu-neko (2604) | more than 2 years ago | (#39235835)

Yup, typical response from physicists for oh I dunno almost the past 100 years. Can't explain something? Must be a new particle...

Yup. Can't explain something, but it would be explained if a certain particle with such and such properties exist, let's go look for it... and lo, there it is! It's amazing what you can discover if you're willing do more than just throw up your hands and say, "hmm, can't explain that."

Re:From my understanding... (1)

Anonymous Coward | more than 2 years ago | (#39237595)

Out of interest, do you seriously believe that "dark matter" is *actually* one type of particle?

Look at it this way. On the one hand, we have 5% of the universe (and about 20% of the matter content) is the standard model, which to our current knowledge contains three flavours of quark and three flavours of leptons at a fundamental level and an absolute menagerie of combinations of these. Why do people - and I most definitely include professionals in this - seem to think that if 5% of the universe can be described by an equation that can be written on a piece of A4 and six particles (along with four or five gauge bosons), 25% of it is described by.... dark matter. Which is apparently one type of particle, described by one equation: w=0. That's frankly not believable.

I can answer my own question, by the way: people believe this because we can't actually parameterise a better model. If you can't distinguish between two models, they're more or less meaningless. When more data comes in, *then* you can think of things more complicated. And at that point I think a lot of people will face reality: dark matter is very likely a mixture of modifications to gravity, the lightest supersymmetric particle (let's say a neutralino), some other particles currently not thought of, massive neutrinos, poor applications of gravitational physics, and Lord alone knows what else.

Re:From my understanding... (1)

Baloroth (2370816) | more than 2 years ago | (#39235117)

No, that isn't far fetched at all, and it is entirely possible (maybe even likely). However, the philosophical principles that guide science dictate that we should reduce effects to the fewest possible number of causes. If two causes suffice to explain the phenomenon, one should not introduce a third. You can introduce new principles/causes/etc ad infinitum, but unless they are required to explain the observations, they are more or less worthless. In other words, one should postulate only as many kinds of matter as have been observed (but not that there are definitely only those kinds).

Re:From my understanding... (4, Interesting)

Rich0 (548339) | more than 2 years ago | (#39235675)

There are other possible ways that the same phenomena could lead to different outcomes. How about this one - galaxies/clusters are composed of stars and hot gas, and that's it - there is no dark matter. However, we exist in a multiverse with many parallel universes overlaying ours but interacting only through gravity. Since matter in different universes attracts each other, galaxies in one universe tend to be piled on top of galaxies in other universes. Much of the mass of any cluster/galaxy is in the hot gas.

Now, let's take the bullet cluster. Let's explain that by the collision of 4 clusters in three universes. Universe A is ours, and B and C are others that are close by and interact gravitationally. Two of the clusters are in A (call them 1 and 2), one is in B (call it 3), and one is in C (call it 4). 1 and 3 overlap, and 2 and 4 overlap. When they cross paths, the hot gas in 1 and 2 interact via electromagnetism, and the hot gas in 3 and 4 only interact gravitationally and aren't slowed down as much. In the end the gas in our universe in clusters 1 and 2 ends up in the middle, and the gas in 3 and 4 are visible as dark matter on the outside.

As the second example let's consider this collision. Let's explain that using 4 clusters in two universes, again with A being ours and B being another one. Clusters 1 and 2 are in ours, and 3 and 4 are in B. 1 and 3 overlap, as do 2 and 4. In this scenario the hot gasses in 1 and 2 interact, and so do the hot gases in 3 and 4. That means that the hot gases all end up in the middle in all 4, and the stars all fly past each other and end up on the outside. So, this time we see hot gas in the middle, plus a lot of dark matter, which is all the hot gas in 3 and 4.

So, we can have "dark matter" behaving in two different ways, not because of any difference in the matter itself, but rather a difference in the space in which it exists.

No doubt somebody much smarter than me has thought up something like this already, and perhaps shot it full of holes as well.

Re:From my understanding... (1)

BiggerIsBetter (682164) | more than 2 years ago | (#39236905)

Interesting theory and similar to things I've wondered about too. It might one of those theories that's very difficult to prove either way.

Re:From my understanding... (2)

boristhespider (1678416) | more than 2 years ago | (#39237961)

What you're talking about is very similar to the effects of braneworld theories, where our universe is living on a 3D brane to which we're confined. There are, of course, other branes hanging around in the wonderful 11D multiverse. In M theory, gravitons are closed strings and can float freely between the branes, while photons (and, indeed, the rest of the standard model particles) are open strings whose ends are confined to a brane. (Note that saying "In M theory" is itself a bit dubious since M theory doesn't really exist, but let's pass over that for a minute.) That means that if two branes pass close to one another, technically galactic clusters on each brane can interact gravitationally, but cannot interact electromagnetically.

Demonstrating much of this properly is, of course, another issue. We don't possess M theory, so we can't solve the system. The best we've done so far is make lower dimensional braneworlds - such as 3+1D branes hanging in a 4+1D universe - and see the effects. And there are some - effective masses for gravitons is one. Less pleasingly, you also have myriad causality issues what with, say, gravitons propagating off one brane and scattering off particles on another brane. If the branes are distorted in the right kind of configuration, an observer on the first brane will see a graviton propagating arbitrarily faster than light.

Then again, all this is basically results found from studying a toy model that people hope will in some way resemble an actual configuration from M theory. The reality may be very different. (And, of course, the reality may bear no resemblence to M theory at all, and may even be that we live in a 3+1D universe the way we've always thought.)

Re:From my understanding... (1)

ChromaticDragon (1034458) | more than 2 years ago | (#39235761)

Nothing likely wrong about positing multiple types of dark matter...

But what I think is really bothering folk about the supposed contradiction here is why would one galaxy or galaxy cluster have one type and another galaxy or galaxy cluster have another? This in and of itself would seem to be a rather flagrant violation of the Mediocrity Principle.

It would seem more likely that both galaxies would have a blend, if you will.

Is there a time component here? Would dark matter be different in one epoch vs. another? Does it evolve or change over time? The Bullet Cluster is 150 million years back. This new set is a couple billion years back. On the face of it, that'd be just another violation of the Mediocrity Principle, just in time rather than space. But who knows...

Re:From my understanding... (1)

Raenex (947668) | more than 2 years ago | (#39236513)

But what I think is really bothering folk about the supposed contradiction here is why would one galaxy or galaxy cluster have one type and another galaxy or galaxy cluster have another? This in and of itself would seem to be a rather flagrant violation of the Mediocrity Principle.

Not necessarily. Galaxies come in many different types:

http://en.wikipedia.org/wiki/Galaxy#Types_and_morphology [wikipedia.org]

Re:From my understanding... (1)

Raenex (947668) | more than 2 years ago | (#39236485)

From my understanding of dark matter, isn't it likely yhat they're looking at two entirely different types of matter?

This was one of the possibilities (the third one below) raised in the article:

"Jee, Babul and their colleagues propose several possible explanations for the discrepancy. One explanation might be that the dynamics of the Abell 520 collision are more complex than the Bullet Cluster's crash. Maybe multiple collisions, involving three or four galaxy clusters, have led to the dark matter pile-up.

Another possibility is that there's actually lots of ordinary galactic material in the core, but it's just too dim to be seen, even by Hubble. That would suggest that the super-dim galaxies in the core have somehow formed far fewer stars than normal galaxies.

The most unsettling scenario proposes that there are different kinds of dark matter, and some of those kinds are "stickier" than others. Abell 520 might have a particularly sticky kind of dark matter that interacts with itself and clumps up like a wet snowball."

Barricade your basement doors!!!!! (1)

rts008 (812749) | more than 2 years ago | (#39234657)

I've seen this before [imdb.com] .

We are all DOOMED!

tribbles! (2, Funny)

Anonymous Coward | more than 2 years ago | (#39234659)

Must be a cosmic pile-up of tribbles.

Re:tribbles! (1)

AbRASiON (589899) | more than 2 years ago | (#39235131)

Sounds like we need one of those incredibly dangerous tribble harvesters.
http://419eater.com/html/tope.htm [419eater.com]

(worth reading)

Awoken (3, Funny)

roman_mir (125474) | more than 2 years ago | (#39234749)

Awoken the Grue has been.

Oddly enough, The Fifth Element is on right now (4, Funny)

GodfatherofSoul (174979) | more than 2 years ago | (#39234755)

Make sure to call me if that blob starts moving towards earth!

Dark MAtter theory now falsifiable? (5, Interesting)

RichyRoo (2553726) | more than 2 years ago | (#39234903)

If Abell 520 has had the DM 'stripped from its galaxies' (from the link) and since DM was originally postulated to explain the difference between theoretical and observed rotation rates of the core and periphery of galaxies... shouldnt the galaxies of Abell 520, stipped of their DM, now be rotating in accordance with the original theory? That is to say, if gravitational theory predicts that, sans DM, the cores of galaxies will rotate more quicky than the periphery, and these galaxies are now 'sans DM', wouldnt that open the opportunity to provide falsification or support to the DM hypothesis by checking if the galaxies of Abell 520 are indeed rotating differently now that the DM has been removed?

Re:Dark MAtter theory now falsifiable? (1)

l0ungeb0y (442022) | more than 2 years ago | (#39235115)

Care to tell us how they were rotating previously?

Re:Dark MAtter theory now falsifiable? (4, Interesting)

RichyRoo (2553726) | more than 2 years ago | (#39235289)

In theory the cores of galaxies should be rotating faster than the periphery, however observation contradicts this. So the hypothesis was postulated that there was additional 'dark' matter surrounding galaxies which could cause the periphery to rotate faster. If Abell 520 has had its dark matter removed, its periphery should be rotating in accordance with standard gravitational theory, rather than as effected by invisible dark matter. Its pretty simple really.

Re:Dark MAtter theory now falsifiable? (1)

osu-neko (2604) | more than 2 years ago | (#39235845)

Yes... and in a few million years, we can compare it to the images we took today and see if that's the case...

Re:Dark MAtter theory now falsifiable? (1)

maxwell demon (590494) | more than 2 years ago | (#39237911)

Ever heard of the Doppler effect?

Re:Dark MAtter theory now falsifiable? (3, Interesting)

mbone (558574) | more than 2 years ago | (#39235891)

In theory the cores of galaxies should be rotating faster than the periphery, however observation contradicts this. So the hypothesis was postulated that there was additional 'dark' matter surrounding galaxies which could cause the periphery to rotate faster.
If Abell 520 has had its dark matter removed, its periphery should be rotating in accordance with standard gravitational theory, rather than as effected by invisible dark matter. Its pretty simple really.

Falsifiable ? Yes, but probably not this way. First off, A520 is a cluster of galaxies, not a single one. The dark matter orbiting the galaxy core is going to be tightly bound to that galaxy, and won't be stripped by a cluster collision. And (see my post below), anyway it's not the stars, but the gas that gets separated from the dark matter.

Must I explain everything???? (1)

sgt_doom (655561) | more than 2 years ago | (#39235099)

Obviously, the Death Star detritus, along with the burntout hulks of various starships blown out of existence by Luke and Hans and that furr-faced fellow, had to congregate someplace........

Throw out the existing theories (1)

grantspassalan (2531078) | more than 2 years ago | (#39235279)

The theories existing now are obviously wrong. Scientists, especially cosmologist these days are always puzzled, perplexed, surprised, mystified and confounded by the unexpected data that does not fit into any of their theories. There are theories that other people have come up with that don't require dark matter, dark energy, black holes and other convoluted mathematical constructs that have never been observed in real life. Maybe it is time to throw out the old theories and consider some of these theories, which up till now have been dismissed as crackpot ideas. Maybe some of those alternate theories that have been labeled “crackpot” need to be looked at more seriously in light of the flood of data confounding, perplexing and fooling current mainstream scientists.

Re:Throw out the existing theories (1)

Daniel Dvorkin (106857) | more than 2 years ago | (#39235517)

Maybe some of those alternate theories that have been labeled âoecrackpotâ need to be looked at more seriously in light of the flood of data confounding, perplexing and fooling current mainstream scientists.

Maybe the crackpots should present some real evidence instead of acting so much like, well, crackpots. Specifically, maybe they should submit their work for publication and stop posting their "results" on web sites full of eye-bleeding color schemes, pretty Hubble pictures (which are, BTW, published by those evil "mainstream" scientists) that have nothing do to with the issues at hand, accusations of censorship and suppression by The Scientific Establishment, and "refutations" of existing theories that all pretty much boil down to "nuh-uh!"

Re:Throw out the existing theories (1)

grantspassalan (2531078) | more than 2 years ago | (#39236827)

Many scientific theories held by the majority, sometimes for centuries, were overthrown by observant people working alone. Some of these were never vindicated by majority scientists until many years after these lonesome scientists died. There are many examples of this. I will just give one.

For centuries it was the consensus among scientists, that the speed of light was instantaneous, that is it took no time at all to travel any distance. There were even “experiments” done with lanterns and shutters on mountain tops to “prove” this scientific “fact”. Then in 1611 A Danish astronomer, carefully observing the Jovian moon Io, noticed that the appearance of it's eclipses were not what they should be according to orbital mechanics. He calculated the speed of light amazingly close to what we know it to be today. However it took another 150 years, before technology advanced enough, to enable countless experiments to finally overturn the stubborn commonly held scientific beliefs of the majority. There are other examples of this sort of thing throughout the history of science.

Re:Throw out the existing theories (2)

maxwell demon (590494) | more than 2 years ago | (#39237943)

Many scientific theories held by the majority, sometimes for centuries, were overthrown by observant people working alone.

But unlike the typical crackpot, they understood the theories they overthrew. And they replaced them with better theories, not with ideas which already had been shown to be wrong long ago. And they didn't have to deny experimental results either, nor claim some conspiracy against their ideas.

Re:Throw out the existing theories (2)

bmo (77928) | more than 2 years ago | (#39235681)

The thing is that the people who are /always/ wrong are the ones who are cocksure, such as yourself.

When you change the model to fit the data, we call that science.

Everything else is snake oil, religion, and dogma.

--
BMO

Re:Throw out the existing theories (1)

Raenex (947668) | more than 2 years ago | (#39235711)

Scientists don't just "throw out" theories if they can be patched and no solid alternative exists. They do, however, look at plausible alternatives:

http://en.wikipedia.org/wiki/Dark_matter#Alternative_theories [wikipedia.org]

Dark matter is just the prevailing theory. Working scientists know that it might be wrong and the equations for gravity may have to be fixed.

Re:Throw out the existing theories (1)

osu-neko (2604) | more than 2 years ago | (#39235857)

There are theories that other people have come up with that don't require dark matter...

These theories are even more at odds with the observed effects here than our current theories. What we're seeing in this case is dark matter behaving in an unexpected manner. A theory that posits dark matter doesn't even exist would have a much, much harder time explaining its observed behavior...

Re:Throw out the existing theories (1)

osu-neko (2604) | more than 2 years ago | (#39235869)

BTW, what you're suggesting here is the equivalent of saying, "oh look, the Earth's magnetic pole isn't moving exactly the way our theory predicts -- we should toss out this crackpot theory that the Earth is round."

Not to be pedantic, but (0)

Shotgun (30919) | more than 2 years ago | (#39235337)

FTS: A report...published in the Astrophysical Journal, raises more questions than answers about a cosmic pile-up that's occurring 2.4 billion light-years away.

Should that be "occured 2.4 billion years ago"?

Re:Not to be pedantic, but (5, Insightful)

Daniel Dvorkin (106857) | more than 2 years ago | (#39235467)

It's pretty conventional, when discussing astronomical observations, to use the present tense for "when we see it." Since it can't possibly have any effect on us before the light from the event gets here (assuming relativity is correct, yadda yadda) this makes sense. Also, having to say "2.4 billion years ago 2.4 billion light-years away" would just get annoyingly redundant after a while.

There's pedantry which serves the useful purpose of correcting other people's mistakes, and then there's pedantry of the "look how clever I am" variety; posts like yours, which seem to get posted to every single story on any kind of astronomical event that takes place outside the solar system, are examples of the latter.

Re:Not to be pedantic, but (5, Informative)

bmo (77928) | more than 2 years ago | (#39235701)

There's pedantry which serves the useful purpose of correcting other people's mistakes, and then there's pedantry of the "look how clever I am" variety; posts like yours, which seem to get posted to every single story on any kind of astronomical event that takes place outside the solar system, are examples of the latter.

There is an excellent word for this and it means far more than just "pedant" and it's Finnish.

The word is pilkunnussija, literally "comma fucker"

The more you know.

--
BMO - perkele

Re:Not to be pedantic, but (1)

Daniel Dvorkin (106857) | more than 2 years ago | (#39235769)

Oh, that's brilliant!

+1 (0)

Anonymous Coward | more than 2 years ago | (#39236035)

Wish I had mod points this evening. I can't wait to drop this word into a conversation!

Re:Not to be pedantic, but (0)

Anonymous Coward | more than 2 years ago | (#39237027)

Those guys serve an important purpose in educating other Finns where to put commas in their sentences. (The guys who wrote up our grammar rules had studied in Germany and made the rules on comma placement as logical as they could, which of course means plenty of exceptions when natural language does not fit their logic.)

Re:Not to be pedantic, but (1)

osu-neko (2604) | more than 2 years ago | (#39235893)

FTS: A report...published in the Astrophysical Journal, raises more questions than answers about a cosmic pile-up that's occurring 2.4 billion light-years away.

Should that be "occured 2.4 billion years ago"?

To be perfectly pedantic, it should be "that occurred 2.4 billion years away". Your "correction" is making an entirely different statement, which although true, is not what the original was saying.

Pressure chamber (1)

drerwk (695572) | more than 2 years ago | (#39235363)

If it gets you you'd best jump into a pressure chamber, it's you only hope.

What happens if it turns out that dark matter is.. (0)

Anonymous Coward | more than 2 years ago | (#39235411)

God?

Seems to fit:
- provides structure
- omnipresent

It's going to really bum some people out if this turns out to be true...

Maybe looking for the "god"-particle is less of a cliche than we think..

Just sayin......

Re:What happens if it turns out that dark matter i (1)

PPH (736903) | more than 2 years ago | (#39235805)

God?

We'll have to revise the Sistene Chapel ceiling, for one thing.

Ditto (0)

Anonymous Coward | more than 2 years ago | (#39235509)

Maybe they pointed the Hubbel at Rush Limbaugh

Don't feel bad (2, Funny)

wbr1 (2538558) | more than 2 years ago | (#39235615)

Mysterious Dark Matter Blob Confounds Experts

My ex-wife confounds me too.

Re:Don't feel bad (1)

datavirtue (1104259) | more than 2 years ago | (#39236105)

Is this where people come after they get divorced? Cool!

Experts Confounded (1)

ThePeices (635180) | more than 2 years ago | (#39235645)

I see the experts were Confounded.

Does anybody know if they were also Baffled, or Stumped? It would also be good to know if they were also left Scratching Their Heads?

Oh yeah, were they Dumbfounded too?

Re:Experts Confounded (1)

bmo (77928) | more than 2 years ago | (#39235819)

"The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt." -- Bertrand Russell

And you have proved which one you are.

--
BMO

A hint on the nature of dark matter. (1)

bocin (886008) | more than 2 years ago | (#39235647)

"We have to learn again that science without contact with experiments is an enterprise which is likely to go completely astray into imaginary conjecture." Hannes Alfven.

The Default (3, Insightful)

rust627 (1072296) | more than 2 years ago | (#39235677)

The default position for scientists is "I don't know"
everything else is trying to define and explain
this is why nothing is set as a certainty but always as a theory
a Theory (theory of gravity, theory of climate change etc.) is usually the best most simple hypothesis that explains experimentally verifiable data.
you can create any theory you want from the incredibly convoluted to the overly simplistic (because god made it so strikes me as an overly simplistic theorem).
Usually the simplest (but not most simplistic) theory will be the one that gains the most credence in the scientific community.
the KISS rule applies very much in science too.

Cold sweat (1)

flyingfsck (986395) | more than 2 years ago | (#39235725)

It must be cold sweat left behind by two fighting galaxies.

Why are we even studying (0)

Anonymous Coward | more than 2 years ago | (#39235747)

Things that probably don't even exist anymore?

Likewise, an alien species looking at Earth is probably seeing a bunch of dinosaurs, and we all know how THAT turned out.

Matter drag (2)

mbone (558574) | more than 2 years ago | (#39235833)

This should not be too confounding. Suppose you have two galaxies collide. The dark matter will sail right through the other galaxy, affected only by the overall gravity. The stars will almost never hit each other, so the vast majority of them will be affected only by the overall gravity too. The gas and dust will not - dust is subject to radiation pressure, and gas (plasma) magnetic fields. Once the gas and the dark matter become separated, there is no guarantee they will ever get back together. As the paper says :

One of the key tools for studying merging clusters is the comparison among the distributions of the three cluster constituents: galaxies, hot plasma, and dark matter. For example, in merging clusters the intracluster medium suffers from ram pressure and lags behind galaxies and dark matter, which are believed to be effectively collisionless. The contrast between collisional and collisionless components becomes highest when we observe merging clusters at their core pass-through, when both the medium velocity and the effect of ram pressure stripping are largest.

Oh wow (1)

identity0 (77976) | more than 2 years ago | (#39236165)

>2012
>Still using Hubble
>Costanza_smirking.jpg

In all seriousness, I am impressed this thing is still working. I would have thought it was retired by now. Way to go, Nasa!

Antimatter (0)

Anonymous Coward | more than 2 years ago | (#39236779)

Antimatter caused the visible/dark matter to come unglued.

Dumped useless ballast (1)

korpique (807933) | more than 2 years ago | (#39237029)

It dragged them down unnecessarily and nobody figured any way to use it for anything so they schemed a plot to leave it behind.

slight difference (1)

slashmydots (2189826) | more than 2 years ago | (#39237217)

They call it dark matter but I call it a mathematical error. That makes the whole situation make A LOT more sense than made-up physics of made up materials actually.
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