Feeding galaxy caught in distant searchlight

Jul 04, 2013
This is an artist's impression of a galaxy accreting material from its surroundings. Credit: European Southern Observatory

An international group of astronomers that includes UC Santa Barbara astrophysicist Crystal Martin and former UCSB postdoctoral researcher Nicolas Bouché has spotted a distant galaxy hungrily snacking on nearby gas. The gas is seen to fall inward toward the galaxy, creating a flow that both fuels star formation and drives the galaxy's rotation. This is the best direct observational evidence so far supporting the theory that galaxies pull in and devour nearby material in order to grow and form stars. The results will appear in the July 5 issue of the journal Science.

Spiral galaxies like our own Milky Way formed billions of years ago in the concentrations that began to grow shortly after the Big Bang. As gas cooled and condensed, stars formed, which, over time, synthesized heavy elements and polluted the galaxy with this enriched material upon their death.

But what that model has not been able to explain is the continuous in some galaxies, despite the constant rate at which galaxies turn molecular gas into stars. The simplest model calls for a closed system and predicts star formation should have ceased long ago due to the limited gas supply.

"It's been a problem," said Martin. Galaxies should use up their gas on a that's much shorter than what has been observed, she explained. In fact our own galaxy should have already run out of gas, but stars continue to form in it. "Galaxies must have a mechanism for acquiring more gas," she continued, adding that, historically, no means has existed to directly detect the inflow of the cold fuel.

Now, however, thanks to the from the quasar HE 2243-60, Martin and her colleagues have been able to observe distinct signatures near a typical star-forming galaxy that indicate the inflow of gas feeding the galaxy. In this scenario, gas is drawn into a galaxy and then circles around it, rotating with it before falling in. Although some evidence of such had been observed in galaxies before, the motion of the gas and its other properties had not been fully explored until now.

The background quasar is, by chance, perfectly well positioned for this study. "This kind of alignment is very rare, but was critical for this study," explained first author Bouché, who is now with the Research Institute in Astrophysics and Planetology in Toulouse, France.

The astronomers used two instruments known as SINFONI (Spectrograph for INtegral Field Observations in the Near Infrared) and UVES (Ultraviolet and Visual Echelle Spectrograph), both of which are mounted on European Southern Observatory's Very Large Telescope at the Paranal Observatory in northern Chile. The new observations showed both how the galaxy itself was rotating and revealed the composition and motion of the gas outside the galaxy.

The result is the discovery of how an active star-forming galaxy feeds its prodigious growth, according to co-author Michael Murphy, from the Swinburne University of Technology in Australia. "[We've] observed, as directly as possible, the feeding process for forming huge numbers of stars very quickly 11 billion years ago," he said. The observation also strengthens the argument that low-mass galaxies are formed through these cold streams, which also allow galaxies to prolong their process.

"It is impressive to see in the data the telltale signatures of this infalling gas matching those expected in numerical simulations," said Bouché.

Explore further: Smallest known galaxy with a supermassive black hole found

More information: This research was presented in a paper entitled "Signatures of Cool Gas Fueling a Star-Forming Galaxy at Redshift 2.3", to appear in the 5 July 2013 issue of the journal Science.

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VENDItardE
1.6 / 5 (7) Jul 04, 2013
"Spiral galaxies like our own Milky Way formed billions of years ago in the dark matter concentrations"

maybe so, maybe not....don't be so sure of yourself.
Fleetfoot
5 / 5 (3) Jul 05, 2013
What's your alternative mechanism for the amplification of the density fluctuations by that era?
cantdrive85
1 / 5 (11) Jul 05, 2013
What's your alternative mechanism for the amplification of the density fluctuations by that era?

By saying "that era", you are implying, if we answer the question as framed, that "that era" is a foregone conclusion. Yet, "that era" is only applicable to the big bang guess, you know the creation "theory" first considered by the theologian Monsignor Georges Lemaître.
You see, from a plasma perspective, imaginary dark matter is not needed to form galaxies. As a matter of fact, galaxy formation and evolution have been reproduced by laboratory experimentation and computer simulation based upon classical physics and modern plasma theory of interacting plasmas. Depending upon how we answer that question can in fact render the question moot, it's a pointless question that requires circular reasoning and only has an answer if the BB ever happened.

"The extraordinary thing is that scientists accept the Big Bang and in the same breath deride the Creationists." Wallace Thornhill
GSwift7
2.3 / 5 (6) Jul 05, 2013
Interesting story, and a lucky find, but it would be nice to have more than one example, in order to look for variations in this pattern and set some constraints. I'm sure they'll find more, if they keep looking.
Requiem
2.8 / 5 (9) Jul 05, 2013
cantdrive85: What is your deal dude?

It seems like you want to sit back and tell everybody they're wrong about everything because this somehow makes you right or something?

Newsflash you stupid tool, everybody realizes that the human race doesn't know all the answers, including and especially the scientists.

Are you also going to sit back and laugh at all those idiots who were wrong as they actually do real work and figure it all out? "Ha moron! Now that you figured out how that works don't you see how stupid and wrong you were, just like I was saying all along?!"

P.S. You're just plain wrong about all the crap you claim has been observed and proven in labs and etc with your crank theory. And again, a theory must be DISprovable before it means anything. I could say that wall switches generate light, and give you "supporting evidence". Get it? Probably not.
GSwift7
3.4 / 5 (10) Jul 05, 2013
cantdrive85: What is your deal dude?


http://en.wikiver...disorder

That's my opinion. He has at least 4 of the indicators, maybe 5, and all it takes to diagnose is 3.

You can tell he's not a simple troll, because he actually believes the stuff he says. That, combined with the deep mis-trust of authority and the inability to learn from mistakes and grow as a person might even make him dangerous to people around him. That's okay though, since he probably doesn't have much social interaction with people. Anyone talking with him in real life would sense something wrong and disengage.
HannesAlfven
1 / 5 (11) Jul 06, 2013
Re: "Newsflash you stupid tool, everybody realizes that the human race doesn't know all the answers, including and especially the scientists."

You're right, and I suspect that he understands that actually. The problem is that everybody is focused upon the "cranks" when they should be far more concerned about the dogma within our systems of authority. It's far easier to silence the cranks than it is to identify and root out the dogma.

Re: "You can tell he's not a simple troll, because he actually believes the stuff he says. That, combined with the deep mis-trust of authority and the inability to learn from mistakes and grow as a person might even make him dangerous to people around him."

Jeff Schmidt's book, Disciplined Minds, exposed the underlying mechanisms for how the physics PhD program works. It's just not what you've been assuming, unfortunately. The undergrad programs aren't so bad, but the graduate programs weed out people who question the dominant theories.
HannesAlfven
1 / 5 (11) Jul 06, 2013
The problem is that people have unquestioningly accepted the notion of the "professional scientist", even though these two words define concepts which are in contradiction with one another. A professional is an obedient thinker, whereas a scientist is supposed to be open-minded to new possibilities. From the book

"Real critical thinking means uncovering and questioning social, political and moral assumptions; applying and refining a personally developed worldview; and calling for action that advances a personally created agenda. An approach that backs away from any of these three components lacks the critical spirit ... Ideologically disciplined thinkers, especially the more gung-ho ones, often give the appearance of being critical thinkers as they go around deftly applying the official ideology and confidently reporting their judgments. The fact that professionals are usually more well-informed than nonprofessionals contributes to the illusion that they are critical thinkers." p41
HannesAlfven
1 / 5 (11) Jul 06, 2013
From page 129 ...

"Beginning physics graduate students must devote an entire year or two of their lives to homework. Indeed, the first part of physics graduate school is well described as a boot camp based on homework. One characteristic of any boot camp is that the subject matter the instructors present in their day-to-day work is not really the main thing they are teaching. Teaching the subject matter is certainly one goal, but it is not the main one. In military boot camp, for example, drill instructors make recruits spend large amounts of time learning to dress to regulation, march in precise formation, chant ditties, disassemble and reassemble rifles, carry heavy backpacks, and so on, yet the main goal of all this is something much more profound: to create soldiers who will follow orders, even to their deaths. Similarly, the most apparent goal of graduate physics courses is to indoctrinate the students into the dominant paradigms, or theoretical frameworks, of physics ..."
HannesAlfven
1 / 5 (11) Jul 06, 2013
"... But the primary goal is to train physicists who will maintain tremendous discipline on assigned problems."

Page 134 ...

"A faculty member who talks informally with a student in the hallway or at the weekly after-colloquium reception inevitably comes away with a feeling about whether or not that student 'thinks like a physicist.' The student's political outlook can easily make a difference in the faculty member's assessment. For example, in the usual informal discussion of an issue in the news, the student who rails against technical incompetence and confines his thoughts to the search for technical solutions within the given political framework builds a much more credible image as a professional physicist than does the student who emphasizes the need to alter the political framework as part of the solution. Indeed, the latter approach falls outside the work assignments given to professional physicists in industry and academe and so represents thinking unlike a physicist's."
HannesAlfven
1 / 5 (11) Jul 06, 2013
Jeff Schmidt was an editor of 19 years at Physics Today when he wrote that book. And needless to say, the American Institute of Physics fired him for it. It wasn't until Noam Chomsky and many hundreds of researchers wrote letters in his support that the AIP was forced to reinstate him. It's actually a bit perplexing that people seem largely unaware of the biggest freedom-of-expression case in the history of the physics discipline.

Peter Woit has gone on the record in the YouTube interview "Piling Conjecture Onto Conjecture" as suggesting that the very reason we don't have a unified theory right now is because the number of ideas being pursued by scientific authorities is really a very small subset of the total.

Fred Hoyle in the Cosmology Quest documentary has similarly railed upon the way in which all ideas in physics seem to originate exclusively from either CalTech or Harvard.

How many critics must speak up before people start to recognize that there is a problem here?
HannesAlfven
1 / 5 (11) Jul 06, 2013
From http://www.julesn...6489.htm

"I got interested in the topic when I was going to professional training myself, getting a PhD in physics at the University of California, Irvine. It seemed like the best of my fellow graduate students were either dropping out or being kicked out. And by 'best,' those were the most concerned about other people and seemed less self-centered, less narrowly-focused, most friendly people ... they seemed to be handicapped in the competition. They seemed to be at a disadvantage not only because their attention was divided, but because their concerns about big picture issues ... caused them to stop and think and question, whereas their unquestioning gung-ho classmates just plowed right through with nothing to hold them back. As I mentioned, there's about a 50% drop-out rate for students entering University programs in all fields; and what I found was that this weeding out is not politically neutral."
cantdrive85
1 / 5 (9) Jul 06, 2013
whereas their unquestioning gung-ho classmates just plowed right through with nothing to hold them back.

Sounds like an astrophysicist, and a few commenters on these threads.
HannesAlfven
1 / 5 (11) Jul 06, 2013
When I think about the big picture of what is happening here, it deeply saddens me. Not only are half of our brightest scientific thinkers being thrown away -- a great number of those because they would not adopt the party line -- but the public doesn't see any of this, because the physics discipline has a very effective policy of refusing to teach the controversies associated with the dominant theories. Much of the public now associates "teaching the controversy" with a form of creationism rather than education reform.

Meanwhile, on the Internet, people who have narrowed their focus so much that all they see are technical debates over the fine details of conventional theory, go out of their way to ostracize and ridicule the very same people who the physics establishment weeded out.

Let's be clear here: If people passionately wish to see a unification of theories in physics within our lifetimes, we need to reform this system -- or create a secondary system just for the "cranks".
Requiem
1 / 5 (4) Jul 08, 2013
yep
1 / 5 (6) Jul 12, 2013
If you ever learn to read here is a bone to choke on.
http://adsabs.har....6...87B