Astronomers Find Star-Less Galaxy 608
Wohngebaeudeversicherung writes "Astronomers have discovered a galaxy about 50 million lightyears away from earth that appears to be composed entirly of dark matter. This galaxy, dubbed VIRGOHI21 is rotating like a real galaxy, at speeds only explainable through massive amounts of matter, thought no single visible star could be detected."
Re: Dark matter is sciences god (Score:4, Insightful)
> ark matter is just another word for "we have no idea"
I think you meant to say that you have no idea.
Re:Dark Matter (Score:5, Insightful)
Re:Black holes? (Score:5, Insightful)
What this tells us is that the density of visible stars in that galaxy (assuming a normal distribution of magnitudes) is low enough that we cannot detect any of them. Someone else care to do the math and tell us what that density threshold is?
When you see "stars" in distant galaxies like Andromeda, what you're really seeing are clusters of stars, though perhaps modern technology has allowed us to resolve single very bright stars, I'm not sure.
As for something blocking our view... that's unlikely, as the dark galaxy was detected by viewing its hydrogen signature in radio wavelengths, so there's no problem seeing it in the correct wavelength.
Most likely (my untrained opinion), this is a galaxy composed of either very small stars or very old (burned out) stars. I'm sure there are good models for describing either. In the first case, for example, I would think that a low initial density of stellar material (mostly hydrogen) would lead to the formation of smaller-than-average stars.
What I think this observation proves is that galactic magnitudes can dip below our viewing threshold in the visible spectrum, and therefore any estimates of the mass of the universe based on visual surveys can be discounted. This makes the closed theory of universal expansion far more likely (e.g. that the universe will expand to a certain point, and then begin to contract until it collapses back into a singularity from which a new Big Bang would arise).
Ok, real astronomers ready your red ink!
Re:Dark matter is sciences god (Score:2, Insightful)
Regardless, so as not to confuse ignorant people as some religious goober will likely see this and go "heeeeeyyyyy yeaaaaaa", "dark matter" is a temporary name given to something that's having an effect we can see, even though we can't see what's actually driving the effect.
We're not saying 'ah yes, this must be what is here', we're saying 'well, something is there as evidenced by this, this, and this, but damn if I can tell you what, so I will call it "dark matter" until I can figure out what it really is'.
Whereas science will continue to try and resolve that open question, religion would just arbitrarily make up some assinine answer on the spot, declare itself completely and unquestionably correct, and then mock anyone who did something so silly as suggest that maybe they should have actually tried some observations and tests before coming to a conclusion.
Re:Anyone Question the Existence of Dark Matter? (Score:5, Insightful)
Keep in mind that our understanding of gravity is that we have no clue what it is. However, our understanding of the effect of gravity has been working fine. The effect of gravity and gravity are two different things. It could very well be that there is absolutely no such thing as gravity and the effect of gravity is actually a side-effect multi-dimensional distortion, or subatomic radiation, or pure heavenly magic. That is why there is a 'theory of gravity' and a set of 'laws of the force of gravity'.
Re:I like the picture (Score:3, Insightful)
Re:Anyone Question the Existence of Dark Matter? (Score:3, Insightful)
huh? you define gravity as the singular instance of an apple falling? It seems perhaps you're using a definition of the word that doesn't correspond to common usage. Most people consider gravity to be a universal force that causes each particle of matter to attract every other particle of matter in a relationship corresponding to the mass of the particles and the inverse square of the distance between them. According to Newtonian physics, which was where the concept was originally formulated, this would result in an Apple falling, roughly, from your hand towards the earth, given that the Earth is the most massive and closest body around.
However, a singular instance of an apple traveling toward the earth, or even a thousand instances, is insufficient demonstration that "gravity exists".
Re:Dark matter is sciences god (Score:2, Insightful)
While not following a strict orthodox religious view, your above statement defines my belief of God quite adequately:
We're not saying 'ah yes, this must be what is here', we're saying 'well, something is there as evidenced by this, this, and this, but damn if I can tell you what, so I will call it "God" until I can figure out what it really is'.
Re:Dark matter is sciences god (Score:2, Insightful)
Re:Black holes? (Score:5, Insightful)
This image and the TERAbytes of data like it that have been collected over such a short time are testimony to why losing Hubble is going to be such a tragedy -- whether or not we understand or accept the reasons it's going to happen.
Re:Dark matter is sciences god (Score:3, Insightful)
Plus, if he RTFA, he'd note that it was actually detected by radiotelescope, so there is no question about its existence. So, yeah, it was a really lame attempt to troll.
Re:Dark matter is sciences god (Score:5, Insightful)
I'm sorry if I sound aggressive. I'm not dismissing the idea of the supremacy of Christianity as an ideology altogether, I just find it very, very arrogant that someone would support that without extremely good scientific proof.
The grandparent didn't express his views with good manners, I'll give you that - but the core idea of his post is still true: The church has through the years made up 'truths' and tried suppress scientific research that tests those 'truths'. Isaac Newton or other christian scientists might have believed in the scientific method, but it seems that the church as an entity does not...
Energy is conserved (Score:5, Insightful)
What I find most interesting about the "dark galaxy" is that it's got plenty of hydrogen but it somehow has not managed to form stars.
Re:Dark matter is sciences god (Score:3, Insightful)
Well, in many forms of religion, it more or less comes down to a recognition of forces and powers that are beyond your understanding. If by "being" you mean "something which is" and by "supernatural" you mean "beyond the purview of human knowledge/understanding", then I suppose what you say is true. Religions tend to talk about "supernatural beings". However, this is not the same as indicating that all religions talk about super-heros that live in the sky on clouds, telling us what to do and judging our actions.
So, no, assuming you're not talking about some niche religion, cult, or your own personal beliefs, it's not the same and doesn't adequately define the TYPICAL view of "god".
I think by "typical" you're indicating "prominent" and "widely publicized". However, part of that is because religions and religious people without highly-defined and judgmental super-hero-type gods, first of all, they don't have highly-structured rules and belief-systems, which means they aren't monolithic. It's easier to talk about what Catholics believe than it is to talk about what gnostics/Buddhists believe, since with Catholics you can pretty much cite the pope as an authority, but gnostics won't agree and there is no authority.
Further, the groups that get the most press and will impress you as most clearly "religious" are the vocal/noisy/imposing ones. The ones who are the sort you're annoyed with. They'll go on TV and tell you you're evil for whatever. It's the religious nuts who blow up abortion clinics and World Trade Centers that get on the news as representing "religious action". They guy down the street who gave to the poor and turned the other cheek, but goes silently about his business without even telling you that he did these things from faith, he's not getting on the news.
The fact is, there are religions that are less definitive, more fluidly practiced, and don't bother to try to convince you. Religious people of this sort are not-at-all uncommon, but they won't necessarily talk to you about it, since they aren't trying to win followers. They especially won't talk to you about it if your the sort of person who goes around complaining about how stupid religious people are.
So while I understand that you're unaccustomed to recognizing religious except when it's prominent, monolithic, and offensive to you, I don't see why that means all the other religious-types out there are necessarily a-typical. Maybe they're just not obvious.
Achk, but this is all off-topic anyhow.
Re:Dark matter is sciences god (Score:4, Insightful)
The problem isn't that everyone who is religious has a closed mind; there are religious people with open minds (even more now that it won't get your burned for heresy). The problem is that some people, who are *very* closed minded use religion as an excuse to believe- or not believe - arbitrary things. I can't say for sure whether these bottom of the barrel "I'm right no matter what" types are products of religion or are merely drawn to it, but I can say that they annoy me, that they fester unchecked in many places, and that they successfully supplant knowledge of reality with fantasy and falsehood to further their agendas.
>>That'a matter for discussion but Religion most certainly does not mean an automatic close minded approach.
True enough in an academic sense, but in the US at least, church and politics are closely tied, and "faith" is frequently used to close people's minds to one thing and/or focus their minds on another thing. I'm not by this saying that religion exists only for that purpose (real religion is imho not about that) but that in practice, it happens, and in my experience, a lot all the time.
>>There is even a school of thought that says without Christianity a lot of Scientific discoveries would have been a really late in coming. Since it's largely respobsible for driving out superstion in a lot of cultures.
Drove out superstition? So, leprechauns are superstition, but angels aren't? Looks to me like christianity replaced one superstition with another. Christianity may (for the sake of argument) be a more advanced form of superstition than faeries and elves and dwarves, but it's still not literal. One may be able to "interpret" religion to find guidance with your life, but the literal view is blatantly superstitious. How is one god better than 10? How are two magical, hidden worlds more real than ghosts walking this world? Sorry to have to ask you that, but I find it outrageously foolish to state that today's religion is less absurd than yesterday's just because the flavor changed.
Re:More on Hawking radiation (Score:1, Insightful)
Hawking radiation is on very firm theoretical grounds, however; decades of work has indicated that there is only one way to make quantum mechanics compatible with curved spacetime at the semiclassical level (the theory of quantum fields on curved spacetime), and that theory unambiguously predicts Hawking radiation. i.e., the curvature of spacetime and quantum nature of matter and radiation make Hawking radiation inevitable.
Actually there's a trinity of ways (Score:3, Insightful)
Re:Actually there's a trinity of ways (Score:1, Insightful)
Incidentally, it's very difficult to consider twistors an approach to quantum gravity, at least one that any work has been done on; almost all work on twistors in gravity has been classical. (And even classical twistors haven't really gotten past self-dual gravity to full GR.) And also incidentally, we still don't know whether LQG is compatible with GR; the semiclassical limit has not been determined.
Re:Dark matter is sciences god (Score:3, Insightful)
>>If you're attacking religion at least get your facts strait.
Often the religious people don't know anything about Aquinas or Descartes. They don't know about philosophy or ethics. They just want to disparage science. These people are poor partners for level headed conversation. Making assertions in a controlled, adult manner won't be repaid with thoughful responses. Instead they spin and spit venom.
>>The pro-religious posters on /. don't bring up these "scientific" errors, why do stubborn pro-science folks bring up layman religion that has nothing to do with real religion?
I can't say I'm following you 100%. But you seem to more interested in an exchange of ideas than in pushing your view, and that's my big issue. In the context of this exchange, I can tell you that I think the "science bots" attack the religion in cases where the other person has already showed that they will not be swayed or back down from an erroneous or offensive assertion on the basis of their religion or faith. Or, if the person is just trolling, the attack on the religion might just be a means to attacking the person.
Also, religion and science and philosophy are all very deep subjects with many layers and nuances. Frequently oversimplifications are made just for the sake of appearance. Evolution is attacked in this way constantly. Religion is also applied incorrectly sometimes. The spiritual teachings of Christianity, IMHO, have intrinsic value. However, I consider a literal interpretation of Genesis to border on idiocy. When I dismiss religion as superstition, it's because I've concluded that the person I'm talking to thinks that reality is a function of the whims of magical ghosts. If I'm discussing religion as a way of connecting with other people or ones own nature (which isn't often) then I know we're not talking about Santa and the Easter Bunny, but about humanity.
Wow, I sure rambled. Oh well. I guess I'm saying that people who think the earth is 6000 years old and use that as the basis for arguing anything falsifiable are fools or worse, and they draw attacks on their religion be being inappropriate.
And of course sometimes people attack religion as a shortcut - you believe X and X is silly so you must be wrong about Y - and that's not so great. In cases where someone is just bashing science or scientists, sometimes turnabout is fair play. Of course it's better if one can just say "Look, you said ABC, but ABC is false because of JKL and QRS and VWX", but often (so often) people take positions whose message isn't factual, but emotional, and that's when the fireworks begin. The AC had a tone of this in his post; he said nothing about politics, but his message evokes the political stage of left and right. I could post on ChristianScienceMonitor that "Bush's claims to be directed by God indicates psychosis not faith", but I'd never win the debate. It would be a flamewar in seconds if they didn't delete the comment outright. There's more at issue than just my assertion that Bush is incorrect to assert that "God" whispered in his ear. Its a case of coloring the forum with an undertone of presumptions. No one is truly neutral (no one) and everyone lives their life with partial knowledge. When people speak in winks and nudges, they have already given up their claim to pseudo-objectivity. They've taken a side, accepted their subjectivity without trying to grasp the subjective truth of the other side. And when they try to push their subjectivity as objective, that's offensive. When I see people doing that, I dig my heels in - I guess I could go all socratic on them, but it would be lost on most of them (by them I mean trolls, I do not mean religious people in general).
Ow, carpal tunnel.