A tale of tails

Dec 06, 2011
A visible light image of the RSCG 42 group of galaxies (CGCG 097−026, CGCG 097−027 and Mrk 0182) in Abell 1367. This is based on a composite of images taken from the Sloan Digital Sky Survey through three colour filters. The white contours show the neutral hydrogen distribution, with the highest contour coinciding with the spiral galaxy GCGC 97-026 and a huge gas tail emanating from this galaxy in a north-easterly direction. Four other galaxies in the RSCG 42 group have associated neutral hydrogen here marked by contour lines.

(PhysOrg.com) -- An international group of astronomers led by Tom Scott at the Instituto de Astrofísica de Andalucía in Granada, Spain, has discovered extraordinarily long one-sided gaseous tails in two groups of galaxies that are amongst the longest structures ever observed in such environments. They emanate from CGCG 097-026 and FGC1287, two spiral galaxies in small groups in the outskirts of the galaxy cluster known as Abell 1367 in the constellation of Leo, at a distance of 300 million light years. The new work, which could lead to a major shift in our understanding of galaxy evolution, is published in the journal Monthly Notices of the Royal Astronomical Society.

Clusters of are the biggest structures in the Universe that are held together by gravity. They are like a huge metropolis populated by galaxies that interact with one another and with their environment, the hot trapped within the cluster's gravitational field. In the last few decades, have revealed that, in order to enjoy life in these big cities, galaxies have to pay an entrance fee: they are stripped of their cold hydrogen gas when they enter.

Without this gas, the fuel for future star formation, they age much more quickly than their counterparts who shun the big conurbations. Scientists believe that this is why clusters of galaxies have a significantly larger fraction of passive, quiescent objects where stars are no longer forming than is found in lower density environments. The research by Scott and his team might change this view, showing that galaxies can be robbed of their gas reservoir well before reaching the outskirts of the metropolis.

The astronomers made their discovery after using the Expanded Very Large Array (EVLA) of the National Radio Astronomy Observatory (NRAO) in the USA to study Abell 1367 in detail. "When we looked at the data, we were amazed to see these tail structures" says Tom Scott.

A visible light image of the FGC 1287 group of galaxies in Abell 1367. This is based on a composite of images taken from the Sloan Digital Sky Survey through three colour filters. The white contours show the neutral hydrogen distribution. The huge gas tail emanates from the edge on spiral galaxy FGC 1287. Two other members of the group have associated neutral hydrogen here marked by contour lines.

'The projected lengths of the gaseous tails are 9 to 10 times that of the size of the parent galaxies, i.e., 520,000 and 815,000 light years respectively. In both cases the amount of cold hydrogen gas in the tails is approximately the same as that remaining in the galaxy's disk. In other words, these galaxies have already left behind half of their fuel for star formation before entering the sphere of influence of the cluster."

The commonly accepted scenario invoked to explain the loss of gas in galaxies is based on the idea that when galaxies enter a big cluster, they lose their gas interacting with the hot intra-cluster medium. Like a meteor entering the Earth's atmosphere, the atomic hydrogen is stripped by the pressure that builds up from moving through the dense, hot gas that pervades the cluster, the stripped gas being dispersed within the intergalactic medium. Scientists call this mechanism ram-pressure stripping.

Image showing a wide angle view of Abell 1367 and the positions of the RSCG 42 and FGC 1287 groups. The cyan contours trace the X-ray emission from the hot intra-cluster gas at the centre of the cluster and the white contours show the cold neutral hydrogen gas detected in the two groups.

However, in this case, the perturbed galaxies are still well outside the sphere of influence of this cluster medium and it is not clear which mechanism is responsible for these unique gas tails.

"We considered the various physical processes proposed by theorists in the past to describe gas removal from galaxies, but no one seems to be able to explain our observations" says Luca Cortese, researcher at ESO-Garching, Germany, and co-author of this work. "Whereas in the case of CGCG97-026, the gravitational interaction between the various members of the group could explain what we see, FGC1287 is completely different from any case we have seen before."

Indeed, ram pressure stripping does not seem to be a viable explanation in this case. As this galaxy is located in the outskirts of the cluster, it lies beyond what is thought to be the sphere of influence of the hot and diffuse gas in Abell 1367. To make things even more complicated, gravitational interactions are apparently unable to explain the extraordinary length of the tail and the lack of any sign of disturbance in the stellar body of the galaxy.

The origin of these extraordinary tails still remains a puzzle for scientists, and they perhaps require some physical mechanism that has not been considered before.

"Although the mechanism responsible for this extraordinary gas tail remains to be determined, our discovery highlights how much there still is to learn about environmental effects in galaxy groups" says team member Elias Brinks, a scientist at the University of Hertfordshire. "This discovery might open a new chapter in our understanding of environmental effects on galaxy evolution."

Explore further: Planetary atmospheres a key to assessing possibilities for life

More information: The new research appears in "Two long tails in the outskirts of Abell 1367", Scott T., Cortese L., Brinks E., Bravo-Alfaro H., Auld R. and Minchin R., Monthly Notices of the Royal Astronomical Society, in press. A preprint of the paper can be seen at arxiv.org/abs/1111.7144

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HannesAlfven
1.6 / 5 (7) Dec 06, 2011
Re: "To make things even more complicated, gravitational interactions are apparently unable to explain the extraordinary length of the tail and the lack of any sign of disturbance in the stellar body of the galaxy."

It seems that science has made some wrong choices in the process of coming to agreement on what we are seeing with our telescopes. After all, were one to step back just a bit and re-visit the claims made by Hannes Alfven, they would find that Alfven's electrical universe exhibits much support from modern observations. We must switch our mental gears, and start the process of growing a fresh limb to the body of science. And we must protect this new electrical line of investigation from hostile attack, as it is supported by many observations of the interstellar and intergalactic mediums.

There is more than enough evidence by now to accommodate the construction of a new all-electric scientific framework, and we can do it without any strange matters or forces.
HannesAlfven
1.8 / 5 (8) Dec 06, 2011
For the large scale view of our electricity-driven plasma-based universe, see The Electric Universe.

For intelligent criticisms of existing quantum theory, and a rock-solid path forward for how to fix these problems, see the Common Sense Science group's publications.

When it comes to explaining how life uses water to harness electricity, read Gerald Pollack's Gels, Cells and the Engines of Life.

Archaeology and geology have been covered in extensive depth by prior generations with the catastrophist-velikovsky debates.

To see how ancient human writings and drawings support the view of an electrical plasma-based universe, check out David Talbott's Thunderbolts of the Gods video on YouTube.

For an understanding of how electrical stars work, see Don Scott's website and book, The Electric Sky.

For interstellar "dust", see Gerrit Verschuur.

A new scientific framework means that there is much, much work to be done.
TimESimmons
1 / 5 (5) Dec 06, 2011
anti-gravity matter drag tails
http://www.presto...ndex.htm
Tuxford
1 / 5 (6) Dec 07, 2011
In LaViolette's continuous creation model, new matter is nucleated faster in regions of higher mass density, such as nearby a galaxy. A galaxy moving through space thereby leaves a trail of new gas formed in the galactic halo region. (Dark matter influence in the halo is likely the precursor condition leading to nucleation.) The formation of tails is simply a consequence of a galaxy on the move. Simply really. Not so puzzling.

The mistake is the assumption that the gas must be pre-existing and originate within the host galaxy. While hard to get over astronomer's presumptions, this model fits the observation, once again. If it walks like a duck....
omatumr
1.5 / 5 (8) Dec 07, 2011
Thanks for the interesting story.

Perhaps these newly discovered tails will help astronomers decide if galaxies are formed by fragmentation or by accretion.

With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
http://www.omatumr.com
jsdarkdestruction
3 / 5 (2) Dec 07, 2011
lol, you guys are too much sometimes.
4 of a kind.
HannesAlfven
1 / 5 (1) Dec 07, 2011
Re: "lol, you guys are too much sometimes. 4 of a kind."

Not quite, actually. The electric universe theory is not based upon a thought experiment. It is a physical theory based upon the observation that cosmic plasmas behave as laboratory plasmas. The spinning ring model for the electron -- which can extend the EU theory -- follows along the same philosophical path, insofar as it identifies the weakest arguments inherent to conventional wisdom. People frequently claim that conventional thinkers *want* mainstream science -- like the Higgs Boson -- to be disproven. And yet, they do not actually put any earnest effort into identifying the mistakes. These mistakes are largely mistakes in logic and reason -- not experiments or observations -- and the pattern that we're seeing is that in each case the errors exist at the very base of the idea -- it's hypothesis (that gravity is the universe's dominant force, that particles can be point sources, that the cytoplasm is a liquid, etc.).
HannesAlfven
1 / 5 (2) Dec 07, 2011
To be clear, anybody who is NOT looking for a new cosmology that works better is simply ignoring the criticisms of conventional wisdom. The large majority of science enthusiasts do not spend the proper time (or simply don't have it to spare) in investigating criticisms of conventional wisdom. The reason you see so many competing theories out there is because these criticisms are VAST. Computational power, amazing telescopes and vast quantities of information does not equate to knowledge or philosophical rigor. We live in an information age, and these simplistic information filters which people have designed to winnow down the total set of ideas are inadequate on the most complex questions man has ever asked.

At the end of the day, it is electricity which is both real and powerful enough to do everything that we see with our scopes. Filaments are to be expected within an electric universe. Plasmas are electrical in the lab, and 99 % of what we see in space is in the plasma state.
HannesAlfven
1 / 5 (2) Dec 07, 2011
Professional scientists could care less about an impending paradigm change. Professional scientists are professional for the very reason that they intuitively know how their project manager wants them to attack a problem. Most are paid to deal with the less exciting problems in science, without complaining. This is how we trained them. Divergent thinkers are expelled from the PhD program, and thrown off of telescopes, to make way for more "meaningful" research. Physics PhD students are oftentimes told to memorize stacks of problem sets to pass their qualifying exams. NONE are ever asked to learn a second worldview, meaning that they get absolutely no training in critical thinking (unlike in other subjects we teach today, like literature and even history). When asked to perform a "forced concept inventory" to test conceptual knowledge, it is clear that most college-level physics students lack the conceptual understanding to even handle the consideration of a second cosmology.

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