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Raging winds up to 10,000 times more powerful than a terrestrial hurricane have been detected streaming away from galaxies and stripping them of star-forming gas, according to a new study.
The strongest winds, observed with the European Space Agency's Herschel infrared space observatory, reach up to 1,000 kilometers per second (2.2 million miles per hour).
The winds could be generated by the intense emission of light and particles from newly formed stars, the shockwaves of stellar explosions, or by the black holes at the center of galaxies, the agency notes in a media advisory.
The finding may help explain why some galaxies suddenly stop forming new stars. Scientists studying the data infer that about 1,200 times the mass of our sun is being lost each year from the galaxies with the most vigorous outflows. That is sufficient to strip them of star-forming gas in as little as a million years.
The fastest of the winds appear to come from galaxies that have the brightest galactic nuclei in which a black hole is feeding from its surroundings, a finding that could be a step towards explaining how elliptical galaxies are formed.
Elliptical galaxies are vast islands of stars that have stopped producing appreciable numbers of new stars because they have exhausted their gas supplies.
ESA explains that as smaller galaxies interact and merge with each other, more food is supplied to the central black hole, making it larger and more active. This, in turn, could result in a more powerful wind, which removes the molecular gas and halts star formation, leading to an elliptical galaxy.
The inhibition of star formation in a galaxy is known as negative feedback.
"By catching molecular outflows in the act, Herschel has finally yielded long-sought-after evidence that powerful processes with negative feedback do take place in galaxies and dramatically affect their evolution," Goran Pilbratt, ESA Herschel project scientist, said in the media advisory.
More stories on violent galactic processes:
- Stars form within black hole's destructive reach
- Starburst galaxy unleashes gassy 'superwind'
- Starbirth goes wild in 'cosmic hurricane'
- Blackholes are a turnoff for star formation
- Giant cannibal galaxy caught in mid-gobble
'Massive molecular outflows and negative feedback in ULIRGs observed by Herschel-PACS,' by Sturm et al., is published in Astrophysical Journal Letters, vol. 733, page L16.
John Roach is a contributing writer for msnbc.com. Connect with the Cosmic Log community by hitting the "like" button on the Cosmic Log Facebook page or following msnbc.com's science editor, Alan Boyle, on Twitter (@b0yle).
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So, as these possibly black hole powered jets of wind "remove" molecular gas from these galaxies, does the gas simply disappear and vanish? No, of course not. So where does it go? Into intergalactic space, where, as I have argued in previous posts, it may interfere with our observation of other far off galaxies, resulting in miscalibrated measurements of their luminosity and therefore also of their mass, which may actually be higher than we think.
Could this be the reason that these galaxies seem to not have enough mass to hold themselves together? If there is indeed more intergalactic matter in the form of diffuse molecular gas than has been taken into account so far, would it still be necessary to postulate the existence of strange and unknown new kinds of stuff (dark matter) to explain what we observe?
We've talked about this all before, so you know I have my own doubts about dark matter and dark energy...
but.. at least in this instance I believe that if we can see this matter now (in whatever wavelength we are looking) we should be able to see it or the remnants of it once it has dispersed into interstellar space. So, on this one I do not believe that this matter is related to the observations that lead scientists to postulate dark matter or dark energy.
I think of it like dust in the wind. While at rest the dust is accumulated on the ground, but disperse it in the wind and there will be ways to be sure there is dust in the wind, there will be tests once could do, no matter how much it has been dispersed. I think of this galactic blow-off in that way, it's matter will be identifiable after the complete dispersal. But with dark matter (and dark energy) there are no direct tests available and so it's difficult for me to understand.
I love astronomy. It's one of the few fields in science where all of the rules are not etched in stone. I remember just 8-9 years ago, taking Astronomy 101, that astrophysicist knew that elliptical galaxies were old, compared to spiral galaxies, but they werent sure why each type formed in the shapes that they do. This article is interesting information filling in that knowledge gap.
Indeed much has been discovered in the last 20 years in astronomy and it's related fields of research. But I would make the argument that many branches of science are not (or may not be) quite as set in stone as some may think. All it takes is one big breakthrough to breakdown that science stone and put everyone on the heels scratching their heads. But that is merely semantics, for the most part I would agree with your comment Cygnus.
Just a thought here, I love all the new data that is slowly coming out. But, one thing that has stood out in my mind for a LONG time is that, from our scale, we see galaxies combining into larger and larger structures, we see some Active Galactic nuclei throwing jets of matter/energy that due to the precession of the black hole, tend to form structures that have 'wavelengths' to them and the like.
What if we are just seeing, on the super galactic scale, what is happening on the quantum scale for us. Galaxies of different sizes could easily be equivalent to atomic nuclei or even quarks for that matter. And why we do not see them as whole atoms is that they are likely in a plasma form at present, but the plasma is cooling and so we are seeing the fusion of atomic elements writ large. Consider that much of the mass that we can see in the Universe is tied up in stars, with their atoms stripped down to plasmas, it is easily possible that we are seeing the fusion that happens in stars in the collision and growth of galaxies. One poster that I have seen here has a web site that shows many of the correlations that I have observed and seems to back up my theory.
Who knows...but the answers are out there, and we are slowly putting the pieces of those answers together...We Live in Exciting Times, and we are just now really starting to find the answers that we need to the questions we have always asked: What is the Universe, and how do we fit into it?
Excellent comment B Honest. If I might play devil's advocate for a moment, according to these newer theories of dark matter and dark energy, all of the matter we are currently familiar with, regardless of it's properties, only makes up a small percentage of the known Universe (something like 7% or some such). I believe it is dark energy that makes up the vast majority of the Universe (up around 80%) and dark matter filling in the rest (about 13%-ish).
Personally, I have always liked the idea of "the big IS the small" like your idea in which galaxies are atoms or parts of atoms. It would really drive home the zen nature of things if that were true. I definitely agree that we live in very exciting times. Some very long-winded science experiments have come on line recently (think Large Hadron Collider = years in the making and now yielding results)... I can't wait to see what the AMS-02 shows us about dark matter, anti matter, and cosmic rays. Years and years of hard work and ingenuity are finally beginning to pay off and we get the benefits of these things. God I love science! ;-)