Galaxies Floating on a Dark Matter Stream 173
Darkman, Walkin Dude writes "A team in Switzerland has discovered that most of the small satellite galaxies around the Milky Way's near-twin, Andromeda, are lined up in a single plane that slices through Andromeda's spiral disc. Using images from the Hubble space telescope, soon to be decommissioned, the researchers found that 9 of the 14 of Andromeda's satellites lay on a relatively narrow plane bisecting Andromeda. From the article: 'The team believes the plane could have formed in several ways. In one scenario, the galaxies may have fallen towards Andromeda along an invisible filament of dark matter. Computer simulations show these filaments can form a cosmic web along which galaxies flow.'"
Sombrero Galaxies and You (Score:5, Interesting)
Does dark matter hold our universe together in a web? Perhaps, though this would mean that there is no such thing as truly empty space as a small amount of dark matter would have to exist. Perhaps what lays beneath the edges of our universe is nothing in the sense of it being devoid of dark matter?
Check this out: From this article [americanscientist.org].
While this article only mentions computer simulations, many scientific groups have gone along further researching, convinced that the cosmic web does exist [ociw.edu]. Some people [roe.ac.uk] have based most of their work on dark matter and the cosmic web though I believe it is still speculation [wikipedia.org] and has yet to be accepted by the science community as a whole. I've read some crazy stuff about dark matter, like how it might be the "gravity particle" that is attracted to matter uniformly and causes the gravitational pull between objects. And even crazier books suggesting that the only way we'll ever be able to communicate between parallel existences is by lowering and raising these gravity particles.
Now, the slashdot community seems to be fairly educated and extremely opinionated so how about it--does dark matter exist? If so, since it is very difficult to detect, what are its defining properties?
Re:Sombrero Galaxies and You (Score:5, Funny)
I think it's more like invisible strands of spaghetti.
Re:Sombrero Galaxies and You (Score:1, Flamebait)
You may be right. If so, that spaghetti is flying around the universe. Now, all we need to do is prove it's affecting evolution, and we've proven that His Noodleyness exists.
Re:Sombrero Galaxies and You (Score:5, Funny)
Or is that effecting evolution?
By the touch of His Noodly Appendage, this sentence could potentially use either affecting [answers.com] or effecting [answers.com] correctly! It truly is a miracle!
Grammar and Spelling Nazis tremble in the face of His Noodily Might!
Re:Sombrero Galaxies and You (Score:2)
Okay, no decent uses of "avolution. How about...
Flying Spaghetting Monster effects avolition ( http://www.answers.com/topic/avolition?method=8 [answers.com] ) -- I'd pray to FSM everyday, but I just don't feel like it.
Flying Spaghetting Monster effects avolation ( http://dictionary.reference.com/search?r=2&q=Avola tion [reference.com] ) -- hence "Flying".
How do you know when the FSM is done? He sticks to the ceiling! Hah!
Re:Sombrero Galaxies and You (Score:2)
That's right. Had spaghetti for dinner tonight.
Re:Sombrero Galaxies and You (Score:2)
Re:Sombrero Galaxies and You (Score:2)
Re:Sombrero Galaxies and You (Score:3, Funny)
Re:Sombrero Galaxies and You (Score:2)
SB
Re:Sombrero Galaxies and You (Score:2)
Bigger mystery (Score:2, Funny)
Re:Sombrero Galaxies and You (Score:1)
It's cold,
and err.. dark,
and umm...
oh yeah, it's matter
It seems (Score:2)
About this "web of dark matter": The WMAP data of the galactic background STRONGLY supports this hypothesis. The anisoropy is just too large, and too soon to be explained by non-external (i.e. non-photon interacting) gravitational influences.
Well... WMAP did... until recently. (Score:2)
Re:Sombrero Galaxies and You (Score:1)
haha joke apart...
this brings in me again the idea that the universe is may be some kind of uber-big life-form... lying in a multi-dimensional world... interacting through gravity.... i dont know...that idea suddenly came to my head...
Yeah me too... (Score:1)
Yeah I get really wierd ideas about the universe when I smoke that suff too...
Re:Sombrero Galaxies and You (Score:1)
Re:Sombrero Galaxies and You (Score:3, Funny)
[sigh] No, it's not.
Re:Sombrero Galaxies and You (Score:1)
Re:Sombrero Galaxies and You (Score:4, Informative)
Now, the slashdot community seems to be fairly educated and extremely opinionated so how about it--does dark matter exist? If so, since it is very difficult to detect, what are its defining properties?
If this [cerncourier.com] is correct, then the Dark Matter riddle has been solved. Basically, it was due to the fact that scientists thought they could safely use the Newtonian limit to General Relativity with galaxies. They were wrong and Dark Matter is a result of this error.
This was reported [slashdot.org] on Slashdot not to many moons ago.
Simon
Re:Sombrero Galaxies and You (Score:2, Insightful)
Re:Sombrero Galaxies and You (Score:5, Insightful)
Unfortunately, the general public only hears about the initial press release, not the work of many other scientists in debunking those results.
Doug
Re:Sombrero Galaxies and You (Score:2)
Interestingly, the Milky Way satellites are also in a plane, which caused a bit of a flap about a year or so ago, as everyone expected the dark matter subhalos (the hosts of satellite galaxies) to be isotropic.
My advisor wrote a paper, however, which demonstrates that
Re:Sombrero Galaxies and You (Score:5, Informative)
Dark matter is just the best model we have right now. It also amazes me how much Slashdot is against the dark matter model. Why is that?
Re:Sombrero Galaxies and You (Score:2)
Re:Sombrero Galaxies and You (Score:3, Interesting)
Re:Sombrero Galaxies and You (Score:3, Interesting)
String theory at least has meshing two obviously true theories together, whereas Dark Matter has the job fixing bad math. And if this article's sugg
Re:Sombrero Galaxies and You (Score:3, Informative)
All of this evidence is sufficient to say that either 1) dark matter exists or 2) our theory of gravity is broken in exactly the way necessary to seem like there's dark matter when there really isn't. #1
Re:Sombrero Galaxies and You (Score:2)
We're talking about thousands of scientific papers going back to the 1930's....
Instead, here are some links to some non-technical introductions:
http://map.gsfc.nasa.gov/m_uni/uni_101matter.html [nasa.gov]
http://astron.berkeley.edu/~mwhite/darkmatter/dm.h tml [berkeley.edu]
http://pancake.uchicago.edu/~carroll/cfcp/primer/d ark.html [uchicago.edu]
http://www.astro.princeton.edu/~dns/MAP/Bahcall/no de2.html#SECTION00020000000000000000 [princeton.edu]
http://zebu.uoregon.edu/text/darkmatter [uoregon.edu]
Re:Sombrero Galaxies and You (Score:2)
However we detect dark matter indirectly through its gravitional pressence. These calculations are done with GR which has been pretty a
Re:Sombrero Galaxies and You (Score:3, Insightful)
Selection bias.
Those with an axe to grind shout the loudest and post the most often. The silent majority just keep scrolling.
Re:Sombrero Galaxies and You (Score:2)
I DO NOT!
Re:Sombrero Galaxies and You (Score:2)
Vogt and Letelier even note:
Re:Sombrero Galaxies and You (Score:2)
No model is better than a bad model.
Re:Sombrero Galaxies and You (Score:2)
Re:Sombrero Galaxies and You (Score:2)
Lack of faith.
Dark matter is an unproven hypothesis (actually, multiple unproven hypotheses) that can be fine-tuned to account for any particular set of observations. However, there is as yet (to my knowledge) no generally accepted, closed set of parameters for dark matter models that will consistently explain all observed phenomena.
The "Dark Matter Problem" is at least tw
Re:Sombrero Galaxies and You (Score:2)
It's not just the slashdot community. Dark Matter is an idea that was come up with to explain events that our math theories, based on observations, could not explain. Large non spherical bodies of mass were needed to explain certain problems with red shift, universe expansion rate not being constant, and other oddities. It's a lot like Aether. Aether was someone's idea to come up with how light travels in wave form. Since our
Empty Space (Score:3, Interesting)
In general, the popular belief is that ALL of space is filled with "quantum foam", which contains a mass of virtual particles whose sum (over any statistically significant volume) will be zero. These virtual particles are not "dark matter", precisely for th
Re:It's defining properties are contradictory (Score:2)
That must be a great way to get tax dollars: ask for billions to research something that doesn't exist, and give it impossible characteristics.
ID (Score:5, Funny)
Re:ID (Score:3, Funny)
Yeah yeah, we get it, fanatics suck. Let's not be fanatical about bringing up the fanaticism of the fanatics, k?
Re:ID (Score:2)
We can't be certain just now, but I think Occam would agree with me.
Re:ID (Score:2)
But, you'll have to agree that in those times spelling was kind of optional, not because people didn't care but because it hasn't been standardised (if two words were pronounciated the same, they were often interchanged; my favourite example is the name of http://en.wikipedia.org/wiki/Sir_Walter_Raleigh [wikipedia.org]). I consider both Ockham and Occam valid and most people would recognize both forms.
Re:ID (Score:2)
- You don't know the power of the dark side.
Stephen Baxter's wet dream (Score:1)
Eric Lerner (Score:5, Interesting)
Eric Lerner [wikipedia.org] is looking less and less like a crank with every new cosmological experiment, I think this is exactly what his plasma filament theory [bigbangneverhappened.org] of the intergalactic medium has been predicting.
He has fellow-travellers... (Score:3, Interesting)
Re:Eric Lerner (Score:2)
Re:Eric Lerner (Score:2)
How do you know how old they are? From the redshift. The big bang predicts the bodies are flying away from us, and the rate they are moving (degree of redshift) indicates the distance they have accrued from the location of the event. Finally, from that distance you calcu
Re:Eric Lerner (Score:2)
Re:Eric Lerner (Score:2)
How do you determine their ages? And how is our sun supposed to get so much in the way of heavy elements from the old stars, when the old stars don't have much to provide? Also, a star with little in the way of heavy elements is likely to eject more matter than a heavy star with lots of iron, which is likely to collapse and start
Re:Eric Lerner (Score:2)
We have models of stellar evolution that do a good job of predicting the observed characteristics of stars. For example, the Sun's mass, rate of fusion, and rough age is pretty well known. We have models that indicate the Sun is about halfway through it's life as normal star. These models fit with observed frequency of stars, isotope distribution, brightness, and other observable components of the population of stars near us.
Heavy stars generate most of the heavier eleme
In another scenario... (Score:5, Funny)
In another scenario, the Flying Spaghetti Monster [venganza.org] might have used His Noodly Appendage to intelligently design it that way. Scientists speculate the arrangement makes it easier for Him to make a bank shot on the 9-ball galaxy.
Right. (Score:5, Funny)
STTNG (Score:2)
Re:Right. (Score:2)
I'm not saying the Styx thing is true, only that eventually, time will tell. And if it doesn't prove to be true now, it's maybe because current instruments are too crude to prove it yet. As someone one said, reality is SO much more weirder than fantasy.
a name for it (Score:5, Interesting)
Re:a name for it (Score:2)
Re:a name for it (Score:2)
Re:a name for it (Score:2)
Old Lady (Score:5, Funny)
So, the old lady was right... it's turtles all the way down.
Occam's Razor Please (Score:4, Insightful)
a) dark matter filaments (modeled on a computer no less). Matter we cannot see; who's existence is contentious, etc.
b) the remnants of a cannibalized galaxy. Solid evidence of this principle abundantly available.
Why leap to the more complicated and, arguably esoteric, explanation?
Re:Occam's Razor Please (Score:2)
Re:Occam's Razor Please (Score:2)
For a GAY band! Ha, ha!
Dark Matter bullshit, admit scientists (Score:5, Funny)
"These findings come as a surprise," stated Dr. Weissmann, lead scientist at the institute. "Before today, we thought dark matter might be, say, an agglomeration of exotic subatomic particles, like muons or 'strange' quarks, signifying a problem with the equations governing space-time. Instead, all that turns out to be bullshit."
Other hypotheses included Cheez-puffs and intelligent end-users. But the conclusive evidence for the new Bullshit Theory of Matter came from the Hubble space telescope, which since 1995 has been sending back data that, according to scientists, is "complete and utter bull."
"Over and over we ran through the equations, and each time we came up with the same answer: This is crap," affirmed Weismann. "It's satisfying, in a way, to be able to say that about your life's work."
-C.
Re:Dark Matter bullshit, admit scientists (Score:2)
Dark matter and the multiverse (Score:3, Interesting)
ahref=http://www.mkaku.org/rel=url2html-18972 [slashdot.org]http: //www.mkaku.org/>
Re:Dark matter and the multiverse (Score:2)
A lot of mysteries are going to vanish once we get a handle on what is really happening with these black holes: The event horizon is where our current theories seem to, well, run into a black h
Obligatory post (Score:2)
Unless if the Xeelee get them first.
Re:Obligatory post (Score:2)
Bow or don't bow, it's all much the same to them. These guys are worse than Cthulhu, they don't even want to eat you... just the sun.
Re: Obligatory post (Score:2)
How do you know you're not bowing behind them or in the wrong direction entirely, given that you can't see them?
Dark Side of the Force (Score:2)
2 cents,
Queen B
Old news (Score:2)
Recommended book (Score:2)
It was the first story from his "Xeelee Sequ
"As below... (Score:2)
Maynard James Keenan
Could dark matter be the ley lines [wikipedia.org] of the universe??
I'm not sure I buy this (Score:2)
Re:Hubble soon to be decommissioned (Score:3, Informative)
[OT, Sorry.]
Um, yeah, that's because several countries have diplomatic relations with NK and are negotiating with them. The US is actually doing the right thing here (or at least what everybody wanted them to do with regards to Iraq), but nobody wants to acknowledge that because of the monkey in the White House.
Re:Hubble soon to be decommissioned (Score:2, Offtopic)
That is so utterly wrong I can't even begin to put words to it. The US will never ever deal with North Korea militarily unless North Korea attacks another nation.
People forget that the capital of South Korea is in artillery range of North Korea. North Korea has a massive amount of chemical and b
Re:Hubble soon to be decommissioned (Score:2)
That is the point. North Korea wont initiate a war because it would go nuclear. The US wont initiate a war because it would involve t
Re:Hubble soon to be decommissioned (Score:1, Offtopic)
It's cheaper/easier to pick on countries that can't fight back - Iraq, and soon Iran (with possibly a stopover in Syria).
Re:First US city? (OT) (Score:2)
Re:Hubble soon to be decommissioned (Score:1)
Fixed that for you.
Re:Hubble soon to be decommissioned (Score:1, Offtopic)
Hubble won't decommissioned soon (Score:3, Informative)
In his zeal to take a political potshot Zonk has ignored the most recent developments. Don't be deceived. NASA administrator Michael Griffin has reconsidered [spacedaily.com] earlier the earlier decision to scrap Hubble servicing. A shuttle crew will indeed have to risk their lives to extend Hubble's life for a few more years. Relax. There should still be lots of money left over to invest in Iraqi freedom, and to kill Al Qaida.
Not quite true. (Score:2)
Atmosphere simply stops some frequencies of electromagnetic radiation, either completely or partially. In case of the Hubble, it can also perform observations in ultraviolet. And although the adaptive optics work wonders regarding the resolution, they can't remove the atmospheric glow and the daytime bright sky, though this is no
Re:Dark matter does not exist. (Score:1)
Are you one of the Men in Black???
(Bad joke. I'm sorry.)
Re:Dark matter does not exist. (Score:2)
Re:Hubble Space Telescope (Score:2)
Well let's see, NASA administrator Sean O'Keefe says it will never be visited by a space shuttle repair mission again, which means it will be history as soon as its batteries or gyroscope fails within the next few years, despite repeated efforts by concerned groups to keep it up and running. I'd call that effectively decommissioned.
From the BBC [bbc.co.uk]after NASA's 2006 budget announcement (in February 2005)...
Re:Hubble Space Telescope (Score:5, Informative)
Um dude, O'Keefe has been gone from NASA for nine months now, your article link is almost a year old. One of the first things that the new administrator Michael Griffin did when he took over the reins was to try to figure out ways to keep Hubble alive. Griffin's an actual scientist, unlike O'Keefe who's a career-track manager. And thus sees the important of Hubble, which has been indispensible for astronomical research.
Direct from NASA's Hubble page [nasa.gov], it says
Yup (Score:3, Insightful)
your article link is almost a year old
I even noted that in my post, to pre-emptively head off any nitpicking. Looking at the page you link to, I see no concrete plans. I see "if", I see "possibility", I see "could", and I see "might". Nothing that says, yes, we will repair Hubble in the mission scheduled for such and such a date. I'm all for a continuance of Hubble service; I just don't see it happening.
O'Keefe has been gone from NASA for nine months now
Yup, I should have said "said", not says. Me
Re:Yup (Score:2)
Re:Yup (Score:2)
Re:Hubble Space Telescope (Score:2)
Do you know something that NASA and us astronomers don't?
Talking to yourself?
Re:ermm.. (Score:2)
Re:ermm.. (Score:2)
Re: Dark Matter theory in laymen's terms (Score:2)
Gods and theology can be theorized and tested too. For instance, "If God is real then I'll get a hot date on Friday night."
Of course the existence of Slashdotters falsifies that particular theological theory.
AFAIK the only theories of God that pass every test are -
Re:Dark Matter theory in laymen's terms (Score:2)
Re: Sombrero Galaxies and You (Score:2)
Presumably they mean it looks like a gravitational effect but we can't see any matter in the right place to have that effect, therefore it is "dark" matter (by definition).
Presumably [i.e. not according to current theory] it could be some force we haven't discovered yet instead of gravity, or some "stuff" we haven't discovered yet other than matter, but since we already have independent reasons to b
Re: Dark Matter over mind? (Score:3, Funny)
To paraphrase the old saw about virtual memory:
If you can see it and it's there, it's matter.
If you can see it and it's not there, it's a virtual particle.
If you can't see it and it's there, it's dark matter.
If you can't see it and it's not there, it's dark energy.