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"Dark Matter" Observed

michael posted more than 12 years ago | from the i-was-blind-but-now-i-see dept.

Space 209

An anonymous submitter writes: "The space news site Space Flight Now has an article about the first direct "observation" of so called dark matter. Galaxies appear to have more gravitation (mass) than we can currently observe. The theory of dark matter tries to explain this missing mass by the existence of massive bodies too faint to detect. These bodies include everything from dim stars to exotic particles called WIMPs. The previously dark matter, a dwarf star, was detected when it passed in front of a brighter blue star, creating a gravitational lens. It is thought that there are many more like it out there creating all that extra gravity, we just can't see them." Wired has another story; or see the European Space Agency's original article.

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FP (-1, Offtopic)

djhankb (254226) | more than 12 years ago | (#2664762)

FP

Re:FP (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2664779)

Dam you djhankb! I thought this was going to be my chance.

Re:FP (-1)

Fucky the troll (528068) | more than 12 years ago | (#2664839)

I sense a disturbance in the force. I need a toilet fast.

Re:FP (-1)

Fecal Troll Matter (445929) | more than 12 years ago | (#2664935)

I sense a disturbance in my anus. I need Taco fast.

Re:FP (-1)

Fucky the troll (528068) | more than 12 years ago | (#2665156)

You know Taco will only create *more* of a disturbance. And you'll get snotted too - a hideous fate for any fellow Troll.



The Slashdot Machine May Fall Victim to the Advances of Taco

ASK any expert to speculate on the future of homosexual activity, and you are bound to hear two words: versatility and CmdrTaco.

Homosexuality is already becoming more and more regular within the Linux community. "Upward Gardeners" that send and receive love letters are increasingly normal within the slashdot community - not just for sexual gratification, but for the disgust of REAL MEN (tm) as well. Queers that can exchange short sharp bursts of semen are also becoming common.

In the next few years, it seems the leading potential victims of Taco may be the regular people. Those who toil on the technical side of things, developing the software and standards that make the technology appear seamless to its users, foresee a day when walls are used routinely for walking with their backs to. They also predict the complete segregation of the two sections of the IT community - Microsoft Users (ie REAL MEN (tm)) and freeloading Open Sores scum.

"One can imagine calling a 'Taco Hotline' that has access to your entire list of gay sexual fantasies," with speech-recognition software aiding the synthesised Taco voice to talk about your personal fetishes", said Vinton G. Cerf, a founder of "Gaynet" who is now a senior vice president at Buttsex.com. "A phonecall can be made to a Tacoline number so that the caller can cum within two minutes of the call being answered" he said.

Such so-called gay messaging systems already exist, but they are not especially easy to use and cost many dollars per minute. "It will be another five years or so before that's really attacked seriously," said Dave Cocker, a consultant who works on Taco's asshole regularly, and is an experienced Taco-snotter.

that makes more sence....... (1)

the_2nd_coming (444906) | more than 12 years ago | (#2664765)

I am glad to see this report, I read some where when I was in highschool that dark matter was this exotic matter that could not be seen even if you had it in your hand....that made no sence to me. I am glad to see a more sensable discription like this.

Re:that makes more sence....... (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2664792)

Hiskool? Be sensibble. I sence that this is not troo.

Here's what doesn't make sense... (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2664795)

You spend all day refreshing the main Slashdot page, in hopes of posting an early, or even the first, comment on a news story that you have very little to contribute to...

Then you see it... A new story. *Pounce*

You feverishly type in your reply, making it appear as though you have a genuine interest in the story, but in your haste, you mis-spell the word "sense," not once, which could simply have been a typo, but twice, confirming that you are indeed an ignorant twit.

Re:Here's what doesn't make sense... (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2664812)

ummmmmmmmmmmmmm.............

no.

Re:Here's what doesn't make sense... (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2664841)

Funny how your off-topic reply to my off-topic reply has not been modded down yet, making it appear on the story page as though you are in disagreement not with what I wrote, but with the parent of my comment.

Re:Here's what doesn't make sense... (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2664880)

not any longer:-)

Re:Here's what doesn't make sense... (0)

Anonymous Coward | more than 12 years ago | (#2664947)

Indeed... Verily, 'tis a shame.

sorry! (2)

LMCBoy (185365) | more than 12 years ago | (#2664850)

We are already pretty sure that most of the missing matter must be non-baryonic (i.e., it must be made of something other than protons, neutrons and electrons).

Re:sorry! (0)

Anonymous Coward | more than 12 years ago | (#2664869)

that is not what the article says...try reading.

Re:sorry! (2)

LMCBoy (185365) | more than 12 years ago | (#2664996)

"try reading"

OK. From the article:

"Observations of clusters of galaxies and
the large scale structure of individual galaxies tell us that no more than a quarter of the total amount of matter in the Universe consists of normal atoms and molecules that make up the familiar world around us."

IOW, at least 75 percent of the universe is made of something other than protons, neutrons and electrons. This dim star is in the 25 percent "normal matter" minority.

hope that helps!

Re:sorry! (0)

Anonymous Coward | more than 12 years ago | (#2665128)

that 75% is pure conjecture.....there is not proof that Wimps exist.

Re:sorry! (2)

LMCBoy (185365) | more than 12 years ago | (#2665166)

"that 75% is pure conjecture"

Actually, no it isn't. It's pretty solid.

"there is not proof that Wimps exist."

True, but I said nothing about wimps. Wimps are but one hypothetical kind of non-baryonic matter. The truth is, we know almost nothing about dark matter, we only know a little about what it is not (i.e., baryons).

Re:sorry! (2)

CheshireCatCO (185193) | more than 12 years ago | (#2665198)

There is evidence that WIMPs are the source of the dark matter, based on the distribution of dark matter in galaxies and clusters. Also, we know of one WIMP, the neutrino. It's mass has pretty well been established as being non-zero. Unfortunately, neutrinoes can't make up more than something like 10% of dark matter.

How long...? (3, Funny)

Reliant-1864 (530256) | more than 12 years ago | (#2664770)

How long until Dark Matter is banned as a circumvention device for light waves?

Re:How long...? (-1)

Klerck (213193) | more than 12 years ago | (#2664821)

Ha ha! Truly a hilarious post! Mod this one right up folks! We haven't heard the "How long 'til it's banned" joke in over two hours!

Re:How long...? (1)

Raymond Luxury Yacht (112037) | more than 12 years ago | (#2665184)

It is thought that there are many more like it out there creating all that extra gravity, we just can't see them

Actually much of the gravitational pull was proven to be caused by Marlon Brando [eiga.com] ...

Fate of the Universe . . . (4, Interesting)

JJ (29711) | more than 12 years ago | (#2664772)

The fate of the universe is held by dark matter. Without dark matter, there is insufficient gravity to bind all matter together forever. If there is enough dark matter, with its attendant gravity, then eventually the universe will collapse back onto itself. Probably the end result of that would be another Big Bang.
What a pair of choices.

Re:Fate of the Universe . . . (2)

the_2nd_coming (444906) | more than 12 years ago | (#2664793)

both cases suck though case either way we are all gonna die......the wimper out theory is a bit more distressing however because who wants to theink of time just ending? a recolaps seems more positive.....yes I know I will be long dead but you think about this kind of stuff when you are a complete dork :-)

The worst theory of them all (2)

HanzoSan (251665) | more than 12 years ago | (#2664847)



Is the theory which says, at any given moment the universe can simply destroy itself, and while the chances are 1 in a billion or something really high and unlikely, the possibility is there for ALL matter in the universe to cease to exsist.

Time wont end, just our lives. Even if matter no longer there in this form, its energy will still be there

Re:The worst theory of them all (2)

the_2nd_coming (444906) | more than 12 years ago | (#2664857)

true but it will be so far dispersed that the universe will approach absolute 0 if not reach it and time stops. the only thing that will happen is the stray quantom fluctuation evey billion years or so.

Re:Fate of the Universe . . . (4, Funny)

archen (447353) | more than 12 years ago | (#2664894)

"we're all gonna die"

I'm going to die in about 50 years (give or take 10), if you're going to die in a couple trillion, I wouldn't be that depressed, but maybe you better live it up while you can.

Expand into nothing, compressed to a single point, eaten by a giant galactic space goat; it's all the same to me. I'd be more concerned about our sun burning out in a couple billion years myself....

Re:Fate of the Universe . . . (0)

Anonymous Coward | more than 12 years ago | (#2664913)

ummmm....did you read the end ot the post?

Re:Fate of the Universe . . . (0)

Anonymous Coward | more than 12 years ago | (#2665123)

If the human race survives itself, perhaps we can escape into Hyperspace when the universe finally dies.

No (2)

HanzoSan (251665) | more than 12 years ago | (#2664820)



Dark matter is increasing, the universe is going to expand until we are so far apart that we all freeze to death.

The universe will not collapse, that theory was proven false a long time ago. Since its proven that we are moving apart, Its safe to assume that we will move apart forever.

Also for big bangs, Big bangs happen all the time, in fact Big bangs are happening right now.

Re:No (2)

the_2nd_coming (444906) | more than 12 years ago | (#2664904)

just cause we are moving apart does not mean that the we will forever, what the hell kind of scientific thinking is that? they do not know how much dark matter there isin the universe, they do know how much normal matter there is.....the normal matter does not add up to create the right amount of gravitational force to keep the Universe together, however Dark matter could be there, infact, they have shown that in the galaxies they have looked at for dark matter that on average, much of the matter that in in a galaxy is dark.....if you take that and apply it to evey galaxy then you can show that we will recolaps...however, you cannot just make a jump like that so it remains that we just don't know...no to mention the dark matter in intergalactic space that could exist.

Re:No (0)

Anonymous Coward | more than 12 years ago | (#2665144)

Please tell me the mistakes in your sig are a kind of ironic joke.

Re:No (2)

Pii (1955) | more than 12 years ago | (#2664918)

The only reason it it safe to make this assumption is that the consequences of having guessed wrong will not be felt for quite some time, and in all likelyhood, humankind will not bear witness to any collapsing universe.

That said, your assumption seems silly to me. You act as though there were no force in the universe which could counter the inertia which governs the universe's current expansion.

I'm no astrophysicist, but I can name two off the top of my head: Friction, and Gravity.

Space is not empty, dispite the rumors you may have heard... Every body in motion meets resistance, because there is no pure vacuum. Those particles do constitute a force, no matter how miniscule, and given enough time, they will win out, just as a rock eventually gives way to the trickle of a tiny stream.

Also, every object currently moving outward from the center of the universe is being slowed but the sum total of all of the gravition of the objects behind it (Objects between a body and the Universal center, and objects moving in other directions from the center). Even though gravity has a rapidly diminsihing effect as distance increases, it never reaches zero. Regardless of how fast, or how far a body is, there will always be more matter (light or dark) generating gravity to slow it.

At some point, I believe the big crunch will come again, just as I believe it came before. I think it's an endless cycle.

Universal centre? (2)

sharkticon (312992) | more than 12 years ago | (#2664964)

Also, every object currently moving outward from the center of the universe is being slowed but the sum total of all of the gravition of the objects behind it.

There's no such thing as the centre of the Universe. If there was we'd be able to tell whereabouts we were because everything would be rushing away from the centre. Instead the Universe is isotropic and homogenous - ie. it looks the same in all directions and from all positions. Wherever you are in the Universe you'll see the rest of the Universe spreading away from your position.

And anyway, whether gravity can slow down the expansion of the Universe enough depends on the amount of matter within it, which is a conserved quantity. Of course, as gravity follows an inverse square law the forces slowing down spacetime expansion get weaker over time, and we just don't know whether there's enough matter so that gravity is strong enough.

Probably not, but who knows?

Re:Universal centre? (2)

the_2nd_coming (444906) | more than 12 years ago | (#2665051)

the center of the univers is at the center of a super sphere. the only way to view it is over time. if we can find a glow at the most far out reach...farther than the farhtes Quasar...and that glow is equal eveywhere, then that is the center of the universe.....it is kind of wierd because the center of the universe will be a point that is at the begining of the universe, but the objects that were around at the big bang, and all that energy, are now at what apears to our 3 dimentional concepts as the "outside"

that is why it is homogenius because of the 4 dimentional nature of the universe.

Re:Universal centre? (2)

sharkticon (312992) | more than 12 years ago | (#2665211)

the center of the univers is at the center of a super sphere.

What supersphere? Do you mean a 4-d spacetime hypersphere? I still don't think that the centre of that has any physical meaning unless you ascribe it as being the initial singularity at t=0 (which probably doesn't exist).

if we can find a glow at the most far out reach...farther than the farhtes Quasar...and that glow is equal eveywhere, then that is the center of the universe.

Are you talking about the microwave background radiation which is everywhere? That's all that's left of the afterglow of the Big Bang, the glow itself stopped after 300,000 years when the energy density of the Universe dropped low enough so that photons stopped interacting with matter so often.

Apart from that you make no sense. What does 4 dimensions have to do with the fact that the Universe is homogenous?

Re:Universal centre? (2)

Pii (1955) | more than 12 years ago | (#2665070)

Then I propose we take Ptolemy's view... I declare Earth to be the center of the Universe.

Seriously, even if no central point can be defined from a distance perspective (which I am perfectly willing to accept), there must still be a gravitational center - a location where the amount of matter, and the average of that matter's distance works out to be roughly equal in all directions.

Again, even if this cannot be condensed to a single point in space/time, the effect of this central area would be the same as it relates to bodies retreating from it.

Of course, this is speculative, and as much as I'd like to see a unified theory of everything someday, I don't know that we'll ever get there. The thing I like about the cyclic Big Bang/Big Crunch idea is that it puts us on a timer! We don't have forever to solve all of the riddles of the universe... It's more like (Forever - 1).

Nope (2)

sharkticon (312992) | more than 12 years ago | (#2665164)

Seriously, even if no central point can be defined from a distance perspective (which I am perfectly willing to accept), there must still be a gravitational center - a location where the amount of matter, and the average of that matter's distance works out to be roughly equal in all directions.

That's the whole point of it being isotropic and homogenous - there is no single preferred point at which you can say "this is the centre". At any point you choose there is a (approximately) uniform distribution of matter in every direction. Sure there are local irregularities (galactic superclusters for instance), but on a large enough scale this uniformity seems to hold.

Of course, this is speculative, and as much as I'd like to see a unified theory of everything someday, I don't know that we'll ever get there. The thing I like about the cyclic Big Bang/Big Crunch idea is that it puts us on a timer! We don't have forever to solve all of the riddles of the universe... It's more like (Forever - 1).

Heh, well the latest theory to come out of superstring research is called the Big Splat, and involves four-dimensional manifolds embedded in a five-dimensional manifold, of which two collide and start the Big Bang...

Re:No (0)

Anonymous Coward | more than 12 years ago | (#2665179)

How can something that we know absolutely nothing about be "proven false"? You, nor anyone else, simply cannot claim such guesses to be fact. This is why its called the big bang theory, because its exactly that, a theory not a fact. Any counter theory (such as the one you propose) is equally as non-factual.

The big bang/crunch theory seems quite plausible because of the fact that gravity is present in every observable object in this universe. For instance, if you could create an absolute vacuum with two subatomic particles existing within and no other internal or external gravitational influences, those particles would eventually come together no matter how far away they were. The universe is no different.

Re:Fate of the Universe . . . (0)

Anonymous Coward | more than 12 years ago | (#2664825)

There's no evidence that after the "Big Crunch" another Big Bang will occur since after the "Big Crunch", time will cease to exist.

Re:Fate of the Universe . . . (0)

Anonymous Coward | more than 12 years ago | (#2664842)

It's also possible that the expansion force will be exactly equalled out by gravity, in which case at some point the universe will stop expanding and remain the same size.

Re:Fate of the Universe . . . (1)

fireboy1919 (257783) | more than 12 years ago | (#2665109)

No its not. At least not under the current model. Its been proven that since gravity is not strong enough to keep the universe from expanding NOW its not going to be strong enough to keep it expanding later due to the conservation of mass (since there is roughly the same amount of mass in the universe always, there is a roughly a constant amount of gravitons, while the necessary force to stop the universe from moving keeps increasing).

Of course, with our microscopic view our theories don't hold a lot of water. If we could visit a couple million planets and get viewpoints from all of those, I expect that a lot of our theories about the Universe would change.

Perhaps the Universe isn't even expanding now, and space is simply a closed hyperparaboloid.

Re:Fate of the Universe . . . (2, Interesting)

Jburkholder (28127) | more than 12 years ago | (#2664909)

>Probably the end result of that would be another Big Bang.

so its possible that the universe has banged, expanded, collapsed in on itself and banged again multiple times already, right? (in fact, you can give yourself a serious headache by pondering the implications that this sequence of events is repeated infinitely, that there was never a 'first' time and there will never be a last).

Re:Fate of the Universe . . . (0)

Anonymous Coward | more than 12 years ago | (#2665018)

wow, dude, that's like , deep...

Re:Fate of the Universe . . . (3, Insightful)

hubie (108345) | more than 12 years ago | (#2664926)

I would be more inclined to say that the fate of the Universe is dependent on whether neutrinos have mass. There are far more neutrinos than any other matter predicted or known (except for photons). If the neutrino has even a tiny mass, the result is most likely a closed Universe.

Re:Fate of the Universe . . . (0)

Anonymous Coward | more than 12 years ago | (#2665039)

I think it's safe to say that if something exists as an actual object, it has mass, even if we can not yet demonstrate to ourselves that it does.

Being able to show that neutrinos have mass would be evidence that they exist as actual objects (or at least "apparent objects"), rather than pure theory.

Re:Fate of the Universe . . . (1, Informative)

Anonymous Coward | more than 12 years ago | (#2665068)

neutrinos are not pure theory, they have een observed in accelerators....and I thought that a few years ago, some european physicists said that they have discovered the mass of a neutrino.

Re:Fate of the Universe . . . (2)

CheshireCatCO (185193) | more than 12 years ago | (#2665214)

I think it's safe to say that if something exists as an actual object, it has mass,

Easily proved untrue: photons have no rest-mass. All tests on photons have confirmed this.

As for neutrinoes holding the fate of the universe: they don't. They can be up to something like 10% of dark matter, but not more, based on the distribution of dark matter in clusters of galaxies.

Re:Fate of the Universe . . . (2, Interesting)

nerdlyone (539405) | more than 12 years ago | (#2664939)

I don't think the argument for dark matter has to do with the expansion/contraction of space-time (i.e., the universe). I think the argument for dark matter is based on gravitational models of galaxies and the idea that, according to current theory, most galaxies do not appear to have enough (visible) matter to create the gravitational force needed to hold that galaxy together. The expansion of the universe appears to be accelerating. See one article on this here. [astronomytoday.com]

Re:Fate of the Universe . . . (1)

Ignominious Cow Herd (540061) | more than 12 years ago | (#2665092)

The opposite of the Big Bang is a Gnab Gib. Read Douglas Adams!

(Hey OmniWeb has a built-in spell checker!)

"I'm not theoretical astrophysicist and I don't play one on Slashdot!"

WIMP (-1, Offtopic)

Anonymous Coward | more than 12 years ago | (#2664773)

j00r m0mm4 is a WIMP

Where's the logic? (0, Redundant)

Reliant-1864 (530256) | more than 12 years ago | (#2664788)

The logic of astrophysicists has always amazed me. We can see dark matter, which is invisable because it sucks in light, because we can see a star from very far away. Wow. We should put these astrophysicists in charge of something more usefull where their unique flair of logic could be of real use.

Dark matter bomb (-1, Redundant)

Anonymous Coward | more than 12 years ago | (#2664789)

I'm going to build a dark matter bomb and destroy all the photino birds......

Peek-a-boo (3, Funny)

DaoudaW (533025) | more than 12 years ago | (#2664798)

The result greatly strengthens the argument that a large fraction of the 'normal' Dark Matter in and around our Galaxy exists in the form of MACHOs and that this Dark Matter is not as dark as previously believed!

Does anyone else have the feeling we are just playing peek-a-boo.

"Hey, its dark in here. Where did everyone go?"
"Ummm, move your hands!?"
"Oh, there they are. That was really weird!"

You've just got to love cosmology...

MACHO, MACHO man. . . (-1, Offtopic)

Limburgher (523006) | more than 12 years ago | (#2664802)

I've got to be, a dim dwarf star man. . . Que es mas MACHO? Tu? Si! Mas MACHO! There are so many possibilities. I have dibs on the next one they find.

Soft Light (1)

jmu1 (183541) | more than 12 years ago | (#2664813)

The reason we can't see the dark matter is due to the proliferation of soft light in the Universe, as was depicted in the X-files episode: Soft Light. ;)

Um, if it's a star it can't be dark matter.... (4, Interesting)

LMCBoy (185365) | more than 12 years ago | (#2664823)

The observed object is a dwarf star. It is luminous. This article should have been titled "Confirmation that one of the MACHO objects is not Dark Matter".

Re:Um, if it's a star it can't be dark matter.... (3, Informative)

nerdlyone (539405) | more than 12 years ago | (#2664955)

I think the term "dark matter" does not necessarily apply only to non-luminous matter. I think it is used to refer to any unobserved matter that can account for the apparent gravity we see in galaxies. MACHOs have been a candidate for dark matter for a while, because they are mostly failed stars that do not emit light (at least not enough for us to see), though they do interact with the EM field. Other candidates for dark matter are indeed non-luminous, even non EM interacting (WIMPS-weakly interacting massive particles--that only interact with the weak nuclear force and gravity, but not EM so they can't be "seen" using light).

Re:Um, if it's a star it can't be dark matter.... (2)

LMCBoy (185365) | more than 12 years ago | (#2665069)

Pretty good point, but there's a big difference between a failed star (or brown dwarf) and a low-mass star like this object. We have a pretty good idea how many low-mass stars there are in the Galaxy, from the statistics of stars in our neighborhood. We already account for the presence of such objects when we compute the mass of known objects in our Galaxy. This object is in the "known" column of the Galactic Census; it isn't missing mass.

Now, if you want to discuss the uncertainty of the low-mass stellar mass function, and say that it's possible that there are lots more of these dim stars than we currently estimate, that's a different story (although no one would recommend making this argument based on the observation of a single object). However, there can't be so many of these little guys as to solve the missing mass problem.

Re:Um, if it's a star it can't be dark matter.... (1, Informative)

nerdlyone (539405) | more than 12 years ago | (#2665181)

Actually, most MACHOs are thought to be failed stars--white and brown dwarfs and the like. I disagree that this object they found is in the "known" column as far as frequency of occurrence. This [cam.ac.uk] article supports me (found on a quick search), as well as many other things I have read. It is not well known how many failed stars populate the universe or even our own galaxy, or even how many white/brown dwarfs may populate the Kuiper Belt and Ort Cloud of our own solar system. This isn't known becuase the objects themselves are very hard to detect, because they don't emit much EM.

Re:Um, if it's a star it can't be dark matter.... (2)

the_2nd_coming (444906) | more than 12 years ago | (#2664982)

the term dark matter refers to matter which we can not see...that does not mean it is not normal matter, just that we can not detect that it is there.

Re:Um, if it's a star it can't be dark matter.... (2)

LMCBoy (185365) | more than 12 years ago | (#2665090)

Right, that was my point. Since we can see this object (see image in article), it can't strictly be called dark matter. OK, that's pretty specious, but see my other posts in this thread for a longer explanation.

Executive Summary: we already knew objects like this existed, and we think we know how many there are in the milky way, so it can't really be part of the solution to the missing mass problem.

Re:Um, if it's a star it can't be dark matter.... (2)

the_2nd_coming (444906) | more than 12 years ago | (#2665147)

dark matter = exotic matter just as much as UFO = aliens

it is just a way to classify something that is yet unexplainable of unobservable either because of lack of technology or lack of power. I am willing to bet that about 50% of the dark matter out there is just planets and moons and asteroids that we can not see or have not looked for yet.

Re:Um, if it's a star it can't be dark matter.... (2)

LMCBoy (185365) | more than 12 years ago | (#2665228)

It's true that calling it "Dark Matter" is just a label for something we know next to nothing about; I think the name itself embodies that ignorance nicely. In fact, we really only know a couple of things about DM: it makes up most of the universe, and most of it can't be made of baryons.

I'm already arguing this with an AC in another thread, but we already know that not more than 25% of the DM can be "normal" stuff (and it's probably a lot lower than that). That's stated explicitly in the article.

Light? (1)

saqmaster (522261) | more than 12 years ago | (#2664829)

I remember an episode of Dr. Who back about 15 years ago that featured 'Dark Light'. There was a briefcase type container which housed some 'dark light' and people were trying to steal it because it was so precious.

So we got Dark Matter, and Dark Fibre ;) so what's this Dark Light stuff about?

Dr. Who is my reference for all things scientific! It's all true isn't it?

Re:Light? (0)

Anonymous Coward | more than 12 years ago | (#2664953)

Absolutely....

I would also suggest you watch stark tng
series. They actaully brought in consultants to
try and gauge what would be coming up

Re:Light? (2, Funny)

iforgotmyfirstlogon (468382) | more than 12 years ago | (#2665053)

Learn about a dark light here [amstel.com] .

The Linux Party (0, Funny)

TRoLLaXoR (181585) | more than 12 years ago | (#2664833)

First, there was a plan: how to bring together the different development groups at work? My boss said there was a sort of tension he thought could be eased by some social interaction. Not easy. Almost all of the different development groups despised each other, each thinking its "art" was more important and eloquent than the others'.

There was the kernel extension developer group, coding mostly in C and some PowerPC and x86 assembler. They worked on making our PCI board work with Linux, *BSD, Mac OS X, QNX, and Solaris. They worked "special hours," coming in at one and staying late, supposedly, until seven or eight at night. They enjoyed Jizz cola and had a penchant for ThinkGeek t-shirts and cracking jokes about Win32 API calls and the dreaded Blue Screen of Death.

We had XML developers too. They worked on our website, documentation formatting, and simple apps to configure the driver software. They used HTML, XSL, JavaScript, and a bit of Java. They typically dressed casually, drank coffee and tea, and liked to work straight from the spec: no "Learn XSL in 30 Days" books were to be found in their cubicle farm.

Then we had the guys who wrote full-out UNIX apps. These guys and the products they wrote had been acquired from another company, and were the source of most of the tension: they'd never really been integrated into our group except that they were physically present with the rest of us. They all had beards or mullets or long, unwashed hair. Many wore suspenders or the afore-mentioned ThinkGeek clothes; some even had Penguin tatooes or small C app code tattooed on them. Their cubicle farm was known for the bleating laughter that exploded when one of them found a "silly" bug on someone else's code, and for the rotten, fetid stench that could only be compared to three-day-old shit reeking from inside a rotting corpse's abdominal cavity.

So, in order to get the guys to "know each other" my boss had asked me to organize a during-hours, alcohol-friendly party. My ideas ranged from a keg or two to live entertainment, AKA strippers. But as to what to get them to actually talk to each other in a human manner I had no clue. So I let it go til the last minute and decided to let my inherent creativity mull it over in the back of my head.

When the day of the party had arrived, the catering company brought in a few trays of lunch meat, chicken, pizza, and side dishes, I had picked up the kegs (all four) from the local brewery, and the big-screen TV and DVD were set up ready to blast the Matrix into the eyes and ears of my co-workers. The eagerness in the the air was encouraging and I thought that loosening up and smiles going on even now were a good sign. I even saw some of the guys who'd known each other previously begin to bunch up, bringing along the co-workers they knew from everyday work.

The first thing everyone did was hit the food line, loading up their plates and grabbing a cup for beer to wash it down with. A few approached me and thanked me for the food; it seems appeasing the belly really did tame the beast. After a few minutes of silence and eating and a few second and third courses, they guys were ready to sit down and be entertained. After asking if anyone needed anything else before the movie started, the lights went out and the Matrix began playing. I heard a few enthusiastic comments and jokes being told.

About half-way through the movie I noticed a lot of the guys, especially from the UNIX app group, were getting up and presumably going to the restroom. No suprise, as the second keg was history by now and the third was probably half-way gone. I also noticed some of the guys bumping into things and stumbling. Alcohol's the social lubricant, eh? Well, not long after, my bladder beckoned and I answered. As I made my way to the restroom, I had a self-satisfied smile on my face: my little plan was working, my boss would be happy, and it might even a Christmas bonus or a promotion (even if in title only).

Well, as soon as I pushed the restroom door open, I knew something was wrong. The smell of vomit was pretty strong and I hoped that it'd only been the work of one guy. But the smell was so pungent! After standing at the urinal, waiting for the golden flow to commence, I stood in silence. It was then that I heard grunting. Listening intently for a few seconds, I hoped whoever was upchucking their beer and munchies wasn't leaving a huge mess for the cleanup crew. After pissing and still hearing the noise, I approached the stall the that moaning was coming from.

"Hey, you alright in there, man?" I asked cautiously.

I was met by silence for a moment. Then I heard a few grunts and concealed giggles. Something was up in there. It was then that I heard what sounded like crying and more moaning. What the fuck? I decided I needed to see what was going on. I didn't want this party to come crashing down around my ears. I pushed the door open hard and then gasped as I saw the most sordid, disgusting thing I'd ever seen in my life.

Standing on either side of the toilet were two if the UNIX app coders, their beards caked with vomit, their pants in puddles around ankles, with erect penises wagging in the air. Doubled over the toilet, his head nearly dunked in the swill, was one of the XML developers. His pants were also around his ankles and what appeared to be a combination of blood and semen were dripping from his torn, ragged anus. He was covered in vomit from head to toe, and he was crying hard into the toilet bowl, its echo an eerie accompaniment to the awful scene I was seeing but not believing.

They two Linux coders slowly turned and looked me straight in the eye, evil grins smeared across both of their bearded faces.

"What in Fuck's name are you doing!?" was all I could force out of my mouth. I still wasn't believing I was seeing this.

Saying nothing, both of the Linux coders rushed me. Being in such a tense state, I threw both of them off and made a break for the door. And the fucking thing wouldn't open. In the follow two seconds that seemed like an eternity, the door was pushed open my way and two more Linux coders came in. Upon seeing what was happening, they immediately grabbed me and were joined by the first two. I was trapped. Then the one guy, who was a dead-ringer for Rasputin, the mad Russian monk, gazed into my eyes and said in a feminine voice, "Looks like Mr. Party is gonna get a taste of the real action!" and cackled insanely.

Cold sweat spurted from the pores on my foreheads and cheeks as I was dragged by the four stinking, polluted hippies into the same stall their previous victim was in. Rasputin spoke again, excitement in his voice.

"Thanks for the pizza and beer, now it's time for the weeners and buns!"

Immediately the first two slogged their pants off and got down on their knees. The other two put there knees in my back and held me on top of the first victim, who now appeared to be unconscious. I heard their belts coming off and their zippers coming down, and some rustling around told me that their pants were coming down also. Then the first two started sucking off the other two, in what I could only call the most enthusiastic blowjobs I'd ever seen in my life. The moaning and slurping sounds turned my stomach and I retched. I could see why the first guy might have vomited.

Eventually Rasputin and his cohort started moaning more loudly, and one of them said "fifteen seconds." This was followed by a series of rapid-fire belching and burping that shook me up and down on the guy underneath me. After about fifteen seconds, all Hell broke loose. The two guys behind me started vomiting on the two guys fellating them and I saw cumshot shoot and mix with the vomit all over the two cocksuckers' faces. It was then that I almost lost. I finally did refund when the first two vile fluids were followed by streams of piss. I heard swallowing and dripping and I yacked all over their first victim's head.

Rasputin cried out like a little girl in ecstasy. "Oh god, I'd been waiting for that all night! This party fuckin' roxorz my coxor!"

Now it was my turn, it seemed, as all four started tearing my pants down. Chunks of vomit-piss-semen fell on my back and soaked through my t-shirt. It was reviling. I shuddered as I felt their cold, clammy hands in my ass-crack and a very indelicate reacharound on my ball-sack. At this point I had no idea who was doing what, and I was just praying that I'd wake up and realize I was drunk and dreaming a la nightmare.

Just then I heard the door boom open and my boss's voice fill the air. The stall door was open and he saw right away the turgid scene transpiring in front of him. His voice was immediately followed by two others, XML developers I knew, and they flew into the stall as best they could and began a fight to save my asshole. The poor guy underneath me had just woken up and started struggling and the extra weight of eight other bodies in the stall must have been suffocating.

"It'll be all right, buddy," I offered to him.

Within thirty seconds I was to my feet and was delivering the most heart-felt kicks to the guts of the rapist faggot Linux coders. Between me, my boss, and the two XML developers, we had the gang of four knocked out in a sloppy, excrement-filled pile of hairy body.

It's now been a month since this horrible incident and I am in regular therapy with a sexual abuse counselor. In response to the terrible outcome of this party, my boss toyed with the idea of selling the group off to another company, sans the four hippies who'd been fired and arrested. After considerable urging on my part, and very open ear from my boss, the whole group was dissolved and the Linux coders lost their jobs. Their product was delayed by a year as my boss began hiring a new development team. We'd found evidence that the whole group had been involved in the planning of the gang- bangs and that had it not been for us everyone would have had a "turn" in the stalls.

If there's one thing we learned from this tragedy is that Linux coders, users, and advocates are desperate cock-lusting homosexual faggots that can't be trusted in any situation, let alone a restroom setting. You've been warned.

On the positive side, though, the whole incident brought solidarity between the other groups in the company and I am now on schedule to get a huge Christmas package that not only includes a gigantic bonus but a month's worth of paid time off and a real promotion.

Re:The Linux Party (0)

Anonymous Coward | more than 12 years ago | (#2664931)

Like dilbert... but better.

The ship doesn't move through space... (1)

davydmadeley (267470) | more than 12 years ago | (#2664835)

It moves space around the ship!!

Of course dark matter exists. It's pooped out by that little monster, Nibbler on Futurama. It powers starships ppl!!!

MACHOS = really big rocks (2)

jspey (183976) | more than 12 years ago | (#2664846)

Correct me if I'm wrong, but the article said MACHOS were just really large clumps of normal mass that don't emit any light, so when they say they've found MACHOS, they mean they've just found stuff. You know, really big rocks and such. It's impressive that they's partially proven a theory that would explain where all the dark matter is, but it really sounds like they're trying to sound impressive when they call what they've found MACHOS. Why not just "rocks", or "stuff"?

Mr. Spey

Re:MACHOS = really big rocks (2)

barawn (25691) | more than 12 years ago | (#2665071)

Actually, MACHOs are a specific thing, as MACHO is an acronym for MAssive Compact Halo Object. This implies that it has significant mass, is quite compact, and located in the halo of a galaxy. This says quite a bit more than "rocks".

Re:MACHOS = really big rocks (0)

Anonymous Coward | more than 12 years ago | (#2665077)

MACHOS really rock here [50megs.com]

Dark Matter Observed... (2)

NMerriam (15122) | more than 12 years ago | (#2664851)

...it's that stuff in the back of my refrigerator!

which means its time to move :)

Galactic vs. extragalactic microlensing (5, Informative)

KjetilK (186133) | more than 12 years ago | (#2664855)

Yep, these are really interesting observations! Galactic microlensing, which is discussed in this article, is a field which is growing rapidly and has attracted a lot of interest. I look forward to seeing the lightcurves of this event.

It was indeed Bohdan Paczynski who wrote the first paper about that specific phenomenon, if I recall correctly, the paper was titled "Microlensing on small optical depths". And indeed, he was the one who invented the term "microlensing".

However, I'm more concerned with "extragalactic" microlensing. The funny thing is that stars in remote galaxy can cause microlensing of even more remote quasars. This was first discussed by Chang and Refsdal in an article in Nature, December 6 1979.

The great thing about this is that in galactic microlensing, there are very few MACHOs between us and the stars, so you would have to watch a lot of stars (millions), whereas in extragalactic microlensing, there will be lots of stars, so microlensing events happen all the time. You only need to separate it from the intrinsic variations of quasar...

Now, galactic microlensing has been a so much bigger field of study than extragalctic microlensing, we haven't really got that much attention. In part, it can be becuase galactic microlensing gives so much more solid results, but then, it is just addressing what's going on in our backyard, while the extragalactic microlensing really deals with the universe... :-)

Re:Galactic vs. extragalactic microlensing (1)

Lozzer (141543) | more than 12 years ago | (#2664945)

What is "Galactic macrolensing"?

Re:Galactic vs. extragalactic microlensing (2)

osgeek (239988) | more than 12 years ago | (#2665134)

Massive objects between us and objects we're observing tend to distort light in various ways. Sometimes that distortion is a really good thing because it focuses the light for us, giving us a better picture of what we're trying to observe.

Whole galaxies can form the basis of such lenses.

Dark Matter Cloud observed headed towards Earth (-1, Redundant)

Anonymous Coward | more than 12 years ago | (#2664887)

Dark Matter Cloud observed headed towards Earth

dwarf star? (-1, Redundant)

Anonymous Coward | more than 12 years ago | (#2664897)

Is a dwarf star a star where dwarfs live on?

Misconceptions (2, Informative)

Marx_Mrvelous (532372) | more than 12 years ago | (#2664903)

I, too, used to think that 'dark matter' was some powerful, mystic thing that sucked in light like a black hole.

My current understanding is that dark matter is just normal matter that doesn't emit light. For reference, all matter does 'suck in' light (meaning the energy is absorbed, usually given off as heat).

So, I'm gonna go soon, and eat my dark-matter lunch :)

Re:Misconceptions (2, Informative)

nerdlyone (539405) | more than 12 years ago | (#2665020)

My current understanding is that dark matter is just normal matter that doesn't emit light. For reference, all matter does 'suck in' light (meaning the energy is absorbed, usually given off as heat). WIMPs (weakly interacting massive particles) are theorized not to interact with the EM field--no photon coupling--so they (theoretically) do not suck light, or reflect it, or interact with it in any way. This is one of the other candidates for dark matter, the more exotic candidate. What this article shows is that they have found "normal" matter that can account for he apparent gravity in galaxies, "normal" meaning regular old EM interacting matter that we can see if only we shine light on it. MACHOs are such normal matter, which we can't see only because they don't emit or reflect enough EM radiation for us to detect, basically rocks in space.

Re:Misconceptions (2)

the_2nd_coming (444906) | more than 12 years ago | (#2665098)

the only thing about wimps is that I have not heard of a study that has prooven that you can make a large chunk of matter with them.....if not it realy does not matter since individual subatomic particles don't reflect light in any large amount (since only one photon can strike it at a time......so realy a wimp that can not form macro matter, like an atom, is not any more impressive than a bunch of 3 quarks flying around.

big fucking deal (-1)

Fucky the troll (528068) | more than 12 years ago | (#2664915)

I've had dark matter in my pants for the past three hours. It *does* increase gravity too 'cause it keeps sticking my pants to my ass.

Doesn't anyone listen to Micheal Jackson... (1)

AwwShazbot (541649) | more than 12 years ago | (#2664916)

It doesn't matter if your dark or light!

damn it... (2, Insightful)

turbine216 (458014) | more than 12 years ago | (#2664927)

My biggest problem with modern science (physics and astrophysics in particular) is this truly inane method of making "conjectural" observations...that is, assuming that and unobservable activity has been proven simply because something observable has occurred. It's an antiquated way of doing things, and it seems totally backwards. This is a good example...all this time, physicists have assumed that "dark matter" - the matter that provides a great deal of the gravitational force that holds the universe together - is "invisible" or "unobservable" or in some extreme cases "existing in a separate yet intertwined reality". Doesn't it make a LOT more sense to think that dark matter is just the stuff floating around that doesn't have any light bouncing off of it? What, just because we can't see it with our super-expensive orbiting telescopes means that it's invisible? I can COMPLETELY believe the idea that dark matter is just regular matter that isn't being illuminated or is not emitting enough radiation for us to detect! But it seems that this, the most obvious explanation, is the last one that physicists want to believe.

I really think it's past time for these researchers to change the way they think about the universe. Stop making it so difficult on yourselves. There really CAN be very simple explanations to difficult problems. And sometimes - sorry to tell you this - you're not going to be able to determine EVERYTHING that you want to figure out. That's the way the universe works. Give it time - a LOT of time. Don't come up with unprovable theories to explain irrational phenomena. LET THEM REMAIN UNEXPLAINED UNTIL WE ARE BETTER ABLE TO OBSERVE THEM.

Re:damn it... (0)

Anonymous Coward | more than 12 years ago | (#2665029)

hey it looks like you have all the answers, maybe you should be in charge of all these phd's, telling them what to do and how to do it. i bet we'd have all the answers w/ u at the helm.

Re:damn it... (1)

superflex (318432) | more than 12 years ago | (#2665047)

the process you have just described is called "the scientific method" by most. it is a well-established and respected system whereby scientists make hypotheses, and then perform experiments to test them. it's been working pretty damn well for the past couple of hundred years.

the only unfortunate part is that astrophysicists can't schedule and perform their "experiments" whenever they like. they have to keep their eyes open for whenever nature decides to show off some of it's wonders.

Nucleosynthesis (0, Informative)

Anonymous Coward | more than 12 years ago | (#2665048)

There IS a reason for believing that MOST dark matter is exotic and that those big dirt clumps (MACHO's) that are only somewhat dark are only a small part of it.


The relative abundance of the light elements is supposed to have been determined by the Big Bang, and that sets a limit on ordinary matter. I also understand that Guth's inflation theory predicts that the Universe has the critical mass density, which is many times both the visible mass as well as the allowed ordinary-matter mass, hence the search for exotic forms of matter (WIMP's -- weakly-interacting massive particals).


Does anyone have good mass census numbers for M1 (fraction-of-critical-mass in galactic stars), M2 (FOCM seeming to hold galaxies together), and M3 (FOCM seeming to hold galaxy cluster together)? I thought M1 = 0.001, M2 = 0.01, M3 = 0.1 is roughly the current numbers. That means that those lumps of dirt (M2 - M1) is less than 1 percent of critical mass, although M2-M1 needs to be some kind of dirt lumps (or mini black holes) not to go flying off.


Does anyone know the FOCM for mass of stuff (baryonic particles) from the Big Bang nucleosynthesis limit?

You obviously aren't a scientist. (2)

mindstrm (20013) | more than 12 years ago | (#2665057)

Well.. neither am I. But that's what science is about. Observation, hypothesis, experimentation, etc.

It's not BACKWARDS. It's a big universe.. so we need to have a good idea of what to look for.

I think it was perhaps thought that, if this 'normal matter' accounted for what we saw, we would SEE MORE OF IT, because it's not hidden.

Oh. BTW. We observe electrons, quarks, and the rest of the subatomic particles only through your so-called 'conjectural' observations. Same with some of the 'properties' of these particles.. they exist purely in a mathematical model that works for a certain set of cases; it's not complete.

The point is that they think it's likely that, given the amount of 'missing' matter from what we have observed to date, there may be some 'exotic' reason we can't see it.

Re:damn it... (3, Informative)

kaisyain (15013) | more than 12 years ago | (#2665084)

.all this time, physicists have assumed that "dark matter" - the matter that provides a great deal of the gravitational force that holds the universe together - is "invisible" or "unobservable" or in some extreme cases "existing in a separate yet intertwined reality".

No they haven't. Let me quote from a Scientific American article on dark matter.


Astronomers and physicists offer a variety of explanations for this dark matter. On the one hand, it could merely be ordinary material, such as ultrafaint stars, large or small black holes, cold gas, or dust scattered around the universe--all of which emit or reflect too little radiation for our instruments to detect.


Hey, notice that part where they say a variety of explanations are offered?

(BTW, what do you mean by "invisible" other than it doesn't have light bouncing off of it?)

Re:damn it... (1)

nerdlyone (539405) | more than 12 years ago | (#2665094)

I hear what you're saying, I too have thought, "Why the hell are they coming up with WIMPs that we have never observed to explain the fact that we just can't see all the necessary matter? Maybe we just haven't seen it because the universe is a dark place." But some particle theories (e.g., supersymmetry) allow (or even require) that particles like WIMPs exist, and if they do, they are a perfect candidate for dark matter.

But I disagree that they need to change their method of inquiry. This very article shows that, given a bit of evidence, cosmologists are very willing to accept the mundane explanation. And this article also points out that they are in fact pursuing the evidence to support the mundane theories.

You portray the scientists as "assuming" many things but I don't see it. The fact that they come up with wild theories does not mean that they are ignoring the obvious. It's jus that, in the absence of evidence, either the mundane or the exotic explanation could be correct. So they don't throw either theory out. I don't see them "making 'conjectural' observations...that is, assuming that an unobservable activity has been proven simply because something observable has occurred." This article certainly does not imply that, quite the opposite in my opinion.

Re:damn it... (1)

Johnny Vector (93021) | more than 12 years ago | (#2665191)

My biggest problem with modern science (physics and astrophysics in particular) is this truly inane method of making "conjectural" observations

No, your biggest problem is reading about modern science on Slashdot. C'mon, people! Jeez, I understand when Terri Gross screws up her science interviews, but we ought to be able to do better. These commments (even the highly rated ones) are the worst description of cosmology I've seen in a long time. Bleah.

Okay, so let's start with this one.

Doesn't it make a LOT more sense to think that dark matter is just the stuff floating around that doesn't have any light bouncing off of it?

That's one possibility. In fact, that is exactly the MACHO (Massive Compact Halo Objects) hypothesis. Okay, quick primer on dark matter: First, there are two kinds of dark matter:

  • The stuff that must be in galaxies to explain their rotation curves
  • The stuff that would have to be there to make the universe flat

The first kind really has to be there, because we can measure its gravitational effect directly. But it ain't stars (we can see them), and it ain't dust or gas, because we can "see" that when we look through it. So that leaves large agglomerations of regular matter (MACHOS) or weakly interacting massive particles (WIMPS). WIMPS could be massive neutrinos, but the best estimate for neutrino mass probably isn't enough to account for it. And yes, the term MACHOS was chosen in response to the term WIMPS.

As for the second kind, the only "evidence" for that has until recently been theoretical. If the inflationary hypothesis is correct, the chances of the universe being as flat as we see it but not exactly flat are very very small. That of course is pretty limited evidence.

However, recent measurements of several separate parameters are starting to converge on a cohesive picture. The universe is flat, but has a term (referred to as "Dark Energy", "cosmological constant", or sometimes "quintessence") which accounts for about a third of the energy of the universe and will cause it to expand forever.

Here are some useful URLs:

Hope that clears up some of the confusion.

There is no dark side of the Moon, really... (2)

dpilot (134227) | more than 12 years ago | (#2664930)

as a matter of fact, it's all dark.

The funny part is, within 90%-95%, this is really true of the entire universe.

Great first step - next... (2)

wnknisely (51017) | more than 12 years ago | (#2664940)

Wonderful bit of observation.

But the teams are going to need to be funded so that they can do a complete survey of a larger area of the sky, and begin to get a bound on the number of MACHOs/galaxy or /unit space. That will let us get at least a rough estimate of how much of the universe's dark matter is bound up in these MACHO's.

Anyone know what the longer term funding situation is here? Is it NSF funded?

Linux Developer Gets Laid! (-1)

CmderTaco (533794) | more than 12 years ago | (#2664944)

Philadelphia, PA - In news that is sure to excite the Linux community, long time Linux developer Todd Stanton got laid.

"I still have trouble believing it myself," said Todd. "I was doing some coding when my power supply blew. Instead of pulling out the spare like I usually would, I decided to head down to Best Buy to check out the new DVD releases. Nothing new was out, so I bought another copy of 'The Matrix' since the one I had was pretty worn out. Turns out the checkout girl was a Matrix fan too and well one thing led to another."

Word spread rapidly on message boards and on IRC. "It's pretty irresponsible of him and shows his lack of dedication to Linux and the open source movement," said Fred Simpson. "If others try to emulate this behavior then a lot of projects could get derailed."

Others like Gary Wilcox were glad to hear the news, "We're tired of all those Microsoft developers shoving their Win-Ho's in our face. Now we can tell them about Todd. Who's laughing now?"

Some developers are also excited that this may increase their chances of getting lucky, but most are being realistic. Walker Crandall said, "We thought we'd all be doing the hokey-pokey after Bill Fitzsimmons got some during the LinuxWorld Conference in 1999. We were fooling ourselves. Nobody got nothing."

This is the third such occurrence for Linux developers since 1991.

Cool but, (0)

Deleted (301806) | more than 12 years ago | (#2664960)

Yoda and the Skywalker family have been using "dark matter" (aka the force) for years..

color me cynical but (1)

nanojath (265940) | more than 12 years ago | (#2665007)

Am I correct in interpreting the phrase "Dark Matter may consist of massive compact objects (MACHOs), such as dead or dying stars (neutron stars and cool dwarf stars), black holes of various sizes or planet-sized collections of rocks and ice" as basically meaning "Dark Matter may just be ordinary shit we already know about but in this case just can't see" ?


I mean, not that dying stars or black holes are merely ordinary, but "Dark Matter" sounded so much more mysterious.

The Fundamental Problem... (1)

Myriad (89793) | more than 12 years ago | (#2665082)

The fundamental problem here in finding this stuff is that it's all pretty much black. And the basic colour of space, you see, is also black. So how are we supposed to see it?

Look out! (1)

CodeWheeney (314094) | more than 12 years ago | (#2665110)

Behind you! The Dark Matter! It's sneaking up on you, can't you see it! Run! Run!!

Interesting effects (1)

reelbk (213809) | more than 12 years ago | (#2665130)

This phenomenon has been around for a while now. If you observe certain distant galaxies, you notice an effect called gravitational lensing which is the dark matter's effect on the light traveling from that distant galaxy to earth. Astronomers have been observing this for a while now and it isn't a new discovery. What is new is the Sudbury neutrino observatory's (SNO) findings. They have discovered that neutrinos have a mass (they were previously thought of as weightless particles). It is beleived that a large source of the dark matter found in the universe consists of these neutrinos. This will allow astronomers to possibly account for the dark matter. If we do have enough dark matter in the universe, it means the growth of the universe will be reversed and it will collapse onto itself. The ammount of observable matter in the universe does not have a large enough gravitational pull to halt this expansion, but the dark matter in the universe may be able to account for the missing matter which will reverse the acceleration which has been going on since the big bang. This growth/collapse cycle may have been going on since infinity as well... It's kind of unsettling.

A Jedi Knight Fifth Element? (2)

3seas (184403) | more than 12 years ago | (#2665203)

Dark Matter is not as dark as previously believed!

Does this mean that the jedi knights are winning with the fifth element weapon?

Star Wars episode III: The Perfect Element, Source of Clones!
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