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Scientists have found evidence of a catastrophic event they believe was responsible for halting the birth of stars in a galaxy in the early Universe. According to their findings, just 3 billion years after the Big Bang, a massive galaxy exploded in a series of blasts trillions of times more powerful than any caused by an atomic bomb. The blasts happened every second for millions of years. “We are looking into the past and seeing a catastrophic event that essentially switched off star formation and halted the growth of a typical massive galaxy in the local Universe,” said lead author Dr. Dave Alexander from Durham University.
Using the Gemini Observatory’s Near-Infrared Integral Field Spectrometer (NIFS), scientists looked at SMM J1237+6203 and noticed properties seen in other massive galaxies near to our own Milky Way, which suggest that a major event rapidly turned off star formation in early galaxies and halted their expansion.
This catastrophic event occurred when the Universe was a quarter of its present age. The explosions scattered the gas needed to form new stars by helping it escape the gravitational pull of the galaxy called, effectively regulating its growth, the scientists added.
They believe the huge surge of energy was caused by either the outflow of debris from the galaxy’s black hole or from powerful winds generated by dying stars called supernovae.
Theorists, including scientists at Durham University, have argued that this could be due to outflows of energy blowing galaxies apart and preventing further new stars from forming, but evidence of this has been lacking until now. The team hopes the new findings can increase our understanding about the formation and development of galaxies.
“Effectively the galaxy is regulating its growth by preventing new stars from being born,” said Alexander. “Theorists had predicted that huge outflows of energy were behind this activity, but it’s only now that we have seen it in action. We believe that similar huge outflows are likely to have stopped the growth of other galaxies in the early Universe by blowing away the materials needed for star formation.”
The Durham-led team now plans to study other massive star-forming galaxies in the early Universe to see if they display similar characteristics.
The research is published in the Monthly Notices of the Royal Astronomical Society.
Source: Royal Astronomical Society
I wonder what that could mean.
Does the galaxy lose all its gas and will never be able to make stars again?
Or is it only temporarily?
Did the MW experience similar events, or what does a galaxy need to undergo such an “explosion”?
And btw: blasts in every second of a million years? That sounds a little far fetched 😉 . That would be 3.16*10^13 events….. 😉
DrFlimmer:
Not half as far fetched as bloody “Birkeland currents” powering stars and stuff! 😉
@ IVAN:
Which is is even less far-fetched than unobservable, undetectable “dark matter” said to hold galaxies together.
Zwicky, Rubin, et al falsified the gravitational model of galaxies decades ago. Why couldn’t science just leave it at that and move on? Nope, gotta’ invent a kludge to hold on to the falsified model.
People in glass houses, and all that…
@mgmirkin yeah yeah yeah, NEXT!
mgmirkin Says:
March 10th, 2010 at 3:13 pm
“Zwicky, Rubin, et al falsified the gravitational model of galaxies decades ago.”
Gotta love completely meaningless and empty statements like that. Then again, that’s pretty much standard for the EU crowd.
One definition of Dark Matter, but similar to most is: Dark matter is hypothetical matter that is undetectable by its emitted radiation, but whose presence can be inferred from gravitational effects on visible matter.
And while we are at it, let us throw the Dark Energy hypothesis in there: The energy that is causing the expansion of the universe to accelerate (speed up).
Those hypotheses may be true but they still haven’t even reached the “theory” stage yet. But some people now believe them as gospel..
What ever happened to Occam’s Razor? Principle that all other things being equal, the simplest explanation is to be preferred.
For me it means that there is something massive causing the gravitational effects on galaxies and other bodies that are “visible” (and everything else in the universe) and we are speeding up because we are being pulled towards it. Not being pushed by some magical force. It’s gravity. We just haven’t reached terminal velocity yet. We see and feel the examples of it all around us. Why do the rules change for some (a lot) of people when we are talking on a larger scale? I believe there is something massive causing this but we have yet to detect it. Makes more sense to me than some massive (yep, its a pun) amounts of unknown, undetectable particles.
Just my two cents worth.. 🙂
Can’t quite parse the article as to whether this was posited to be one event (The Big Quench?) or an event that individual galaxies suffered in turn. Also, is there a more specific reference to the original academic article? Thanks!
Do you have a subscription?
http://www.ras.org.uk/index.php?option=com_content&task=view&id=138&Itemid=89
A little more info..
http://www.ras.org.uk/index.php?option=content&task=view&id=1719&Itemid=2
Do you have a subscription?
ttp://www.ras.org.uk/index.php?option=com_content&task=view&id=138&Itemid=89
A little more info..
ttp://www.ras.org.uk/index.php?option=content&task=view&id=1719&Itemid=2
Dave Alexander profile..
ttp://www.dur.ac.uk/physics/staff/profiles/?username=dph0dma
Al Hall Says:
March 10th, 2010 at 5:12 pm
“What ever happened to Occam’s Razor? Principle that all other things being equal, the simplest explanation is to be preferred.”
Occam’s razor is simply a way of choosing between two competing theories – if the two theories are indistinguishable in terms of their predictive and explanatory power, then all else being equal, there is no justification for accepting a theory with unnecessary complications. This is simply not the case here – DM models ARE individually distinguishable in terms of their predictions and explanations for various phenomena. This can, and is being, tested by experiment and observation. Many simplistic views have already been entirely eliminated, replaced with more nuanced models. Read up on the Wiki article for DM for a basic overview of some of that work.
Occam’s Razor also does not state that we as scientists shouldn’t speculate (all scientific theory is initially borne of speculation), or that everything should be paired back to the bare minimum of observable facts, so long as speculations are acknowledged. I think you’d be hard pressed to find any physicist or astronomer who’d take particular DM or DE models as gospel. But the observations are clear, and multiple different lines of evidence point to non-baryonic dark matter as forming a significant part of our universe. We have to then speculate a little as to what it may be, and how we may work out what the hell is going on in this brilliant little universe of ours.
Personally, I don’t see why people have such a hard time believing that DM could consist of exotic particles or something else we haven’t yet experienced in physics. The biggest theme in the history of physics for pretty much the whole of the last century has basically been a story of the continual discovery of more and more new and exotic particles, pretty much every time we move to higher collision energies. There are very tempting and beautiful extensions to the Standard Model of particle physics that fix current issues with the model beautifully, and which basically predict particles that will only interact gravitationally when we reach slightly higher energies. I think it would take a brave man to bet against this overwhelming trend, but I guess we’ll see soon enough…
Astrofiend –
Thanks for proving one of my points off the bat… Neither DM or DE are theories yet.. We need convention for that…
As I said, the hypotheses may be true.. And you are right, with the current way of thinking, these are indeed different animals… But with what I was saying there is most definitely a relationship between them… Gravity… Gravity will explain both.. If we do find in the future a “super mass”, it will explain both.
As for finding “exotic particles” that don’t ‘show’ themselves to our limited technology, that may be true as well.. Hopefully the LHC will tell us something.. If they ever get the freakin’ thing online at full capacity.. I’m not convinced the Higgs boson exists.. Maybe it does but in my world, if you cant reasonably confirm or prove something…, then it doesn’t exist…. So for the time being, I go back to Occom’s Razor… What makes the most, simplest sense?
Theories about hypotheses are fine but theories about theories are better.
Have you ever heard of the Superconducting Super Collider?.. I was very unhappy when that project was canceled.. Now… Hmmm.. I don’t know… But I do wish the LHC the best in whatever they are hoping to accomplish. And hope it can answer a few of our questions.
HI Nancy,
The link given for the Royal Astronomical Society leads to the Royal Society!
The url should be http://www.ras.org.uk the original PR is given there.
Gee, Ivan, although you are right of course, but what have you done?? 😉 I hoped we could speculate and discuss about this article and my questions, but now it has turned into madness, again! 😉
Btw; Dark Matter is a theory, because (although we don’t know what it is) we have some good ideas what it can be, and those ideas can be tested! This makes DM a theory. Same is true for DE. However, AFAIK, this is not true for, say, string theory.
@ Al Hall
A “great attractor” somewhere does not make much sense. In fact, it would be against the idea that our place is not special, which is important. But a “great attractor” would be special. That’s a problem…
@ Al Hall,
Yep – I was very disappointed that the SSC didn’t end up making it. And as far as the Higgs goes – you’re a brave man indeed to bet against it. As for DM and DE – the subject is too loaded to be trashed out again here.
Back to the Higgs though – it could be a while before we find out about that one – I read today that the LHC will be shutting down for over a year at the end of 2011 to address some design flaws that will stop it being able to reach it’s highest design energies before they are addressed. I guess they plan to run medium energy collisions for a year to see if they can catch the Higgs down the low end of the mass scale, and then fix her up to dive a bit deeper into the particle ocean.
@ DrFlimmer,
Sorry about that, but I had a hard day yesterday and I just had to rant!
Bring it on Ivan – arguing is so therapeutic sometimes…
This string of massive explosions, gives me
the impression that we have a run away process here, It looks like an chain reaction?
After all it is an fusion process that takes place in the forming of a start?
Any phycisist knows, that conditions have to be perfect to make an star? Just like everything ells it can go wrong, hence a chain
reaction? Is this a possibility?
@ Bravehart
It’s rather simple to make a star. You just need enough mass collapsing on itself, and then you get a nice star. Nothing special at all. And since most stars are not really connected to other stars, there is also no chain reaction possible, so that if one star blows up the others follow. That’s not possible.
And if you thought of chain reactions on earth, that’s fission and not fusion – maybe you confused them? (The English words are quite close to each other ;))
@ Ivan3man
It’s all right. I hope you do better, now! 😉
“An artist’s representation showing outflow from a supermassive black hole inside the middle of a galaxy. Credit: NASA/CXC/M.Weiss”
Looks like the energy and the out flowing material is escaping at the poles in cone shaped jets but, the NIFS caption says:
“the contours show how the blast of energy is traveling through the galaxy”.
Which is it? These articles can be sometimes confusing to me. If it is escaping via the bi-polar jets, where does it ultimately end up once it escapes the gravitational influence of the galaxy and what is this energy/material? Could it be non-interacting “cold” exotic stuff that we cannot see or detect disbursed into and around the halo After all that had to be one hell of an “exciting” high energy ride out of the well. If we assume that every massive galaxy went through this energy outflow phase in the early universe then there has to be a whole lot of this stuff floating around the fringes of all the galaxies. Maybe we could call it cold dark matter.
Here’s a wild idea; space was a lot closer 3 bys post BB and hence all matter was closer. Like stars, maybe there is a mass limit for black holes as well and during this close and chaotic time they gorged until they reached this limit and there after, “rapidly” (every second?) ate and “burped” for those millions of years until the meal was reduced to a few “crumbs”. The jets we observe from blazars are just overeating belches of reformated information; Hawking reigns. lol Okay, my weekly rant is over.
Wouldn’t the shock waves from all of these massive explosions slamming into the free standing gases help to CREATE stars, even if these new stars are pushed away from the galaxy by the force of the explosions? This is one way that gas in galaxies get put onto the path of gravitational collapse, isn’t it?
@Mr. No.Scope
Indeed they would, if they slammed into large quantities of relatively cold gas/dust.
However i believe what this depicts is a galactic superwind. Hot gas that gets heated even more and pushed out of the galactic plane by winds from massive newborn stars, and shockwaves from supernova. These superwinds are common in so called starburst galaxies, like for example the nearby M82.
http://en.wikipedia.org/wiki/Messier_82
Note the huge swats of hot gas above and below the main parts of the galaxy, most of that is believed to be blown away from dense knots of very active starformation.
I suspect what this article is describing is a starburst galaxy on speed, an early and even more active galaxy than M82.