VLA reveals spectacular 'halos' of spiral galaxies

VLA reveals spectacular 'halos' of spiral galaxies
Composite image of an edge-on spiral galaxy with a radio halo produced by fast-moving particles in the galaxy's magnetic field. In this image, the large, grey-blue area is a single image formed by combining the radio halos of 30 different galaxies, as seen with the Very Large Array. At the center is a visible-light image of one of the galaxies, NGC 5775, made using the Hubble Space Telescope. This visible-light image shows only the inner part of the galaxy's star-forming region, outer portions of which extend horizontally into the area of the radio halo. Credit: Jayanne English (U. Manitoba), with support from Judith Irwin and Theresa Wiegert (Queen’s U.) for the CHANG-ES consortium; NRAO/AUI/NSF; NASA/STScI

A study of spiral galaxies seen edge-on has revealed that "halos" of cosmic rays and magnetic fields above and below the galaxies' disks are much more common than previously thought.

An international team of astronomers used the Karl G. Jansky Very Large Array (VLA) to study 35 edge-on spiral galaxies at distances from 11 million to 137 million light-years from Earth. The study took advantage of the ability of the VLA, following completion of a decade-long upgrade project, to detect radio emission much fainter than previously possible.

"We knew before that some halos existed, but, using the full power of the upgraded VLA and the full power of some advanced image-processing techniques, we found that these halos are much more common among spiral galaxies than we had realized," said Judith Irwin, of Queen's University in Canada, leader of the project.

Spiral galaxies, like our own Milky Way, have the vast majority of their stars, gas, and dust in a flat, rotating disk with . Most of the light and radio waves seen with telescopes come from objects in that disk. Learning about the environment above and below such disks has been difficult.

"Studying these halos with radio telescopes can give us valuable information about a wide range of phenomena, including the rate of within the disk, the winds from exploding stars, and the nature and origin of the galaxies' magnetic fields," said Theresa Wiegert, also of Queen's University, lead author of a paper in the Astronomical Journal reporting the team's findings. The paper provides the first analysis of data from all 35 galaxies in the study.

To see how extensive a "typical" halo is, the astronomers scaled their images of 30 of the galaxies to the same diameter, then another of the authors, Jayanne English, of the University of Manitoba in Canada, combined them into a single image. The result, said Irwin, is "a spectacular image showing that and magnetic fields not only permeate the galaxy disk itself, but extend far above and below the disk."

The combined image, the scientists said, confirms a prediction of such halos made in 1961.

Along with the report on their findings, the astronomers also are making their first batch of specialized VLA images available to other researchers. In previous publications, the team described the details of their project and its goals. The team has completed a series of VLA observations and their latest paper is based on analysis of their first set of images. They now are analyzing additional datasets, and also will make those additional images available to other scientists when they publish the results of the later analyses.

"The results from this survey will help answer many unsolved questions in galactic evolution and star formation," said Marita Krause of the Max-Planck Institute for Radioastronomy in Bonn, Germany.


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Journal information: Astronomical Journal

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Oct 13, 2015
we found that these halos are much more common among spiral galaxies than we had realized,"

And no mention of Fermi Bubbles. Shame.

http://phys.org/n...axy.html

http://phys.org/n...ter.html

http://phys.org/n...les.html

http://phys.org/n...ers.html

So why should halos be a surprise in spirals actively growing (and ejecting) from there cores?

Oct 13, 2015
"We knew before that some halos existed, but, using the full power of the upgraded VLA and the full power of some advanced image-processing techniques, we found that these halos are much more common among spiral galaxies than we had realized..."

They said, surprising no one...

"The combined image, the scientists said, confirms a prediction of such halos made in 1961."

Can anyone here tell me who made this prediction? Not exactly a very detailed explanation.

Oct 13, 2015
Sigh:

I made the prediction. Well, not in 1961...I made the same prediction independently.

Remember, I was the first to predict a 100billion mass black hole and a trillion mass black hole too, so when they find those just remember it.

It's farts in the wind compared to the scale of the universe.

===

Now if only we spent all those billion dollars and trillion dollars doing useful things, we could have had an orbiting array of radio telescopes around Earth, the Moon, and Mars and have like 100 times the resolution of the pathetic VLA.

Oct 13, 2015
Uh, Returners, that doesn't exactly answer the question I'm asking lol. If you want to claim that this prediction is yours, then awesome. But, I'd rather know who within the accepted scientific community made this prediction. That's what's relevant in reference to the article.


Oct 13, 2015
I would be interested in a more detailed, itemized data set of the elements, isotopes, and compounds found in the halo clouds, and if possible their ratios. I don't know whether they have good enough resolution to do that yet, but if they made my orbital radio telescope plan (~12 nodes orbitting each for the Moon, Earth, and Mars) they could get massively better resolution and probably make that sort of determination.

This is interesting because I would like to know whether certain elements, such as lighter hydrogen, escape the galaxy or not. I suspect the heavier elements, such as oxygen,do not escape because they would be harder to accelerate by the explosions.

This information might be useful to me for helping determine some ideas I have about the true nature of stars, and how old the universe really is, etc.

I'm gonna bet that the most common compound in these halos is Water...

Oct 13, 2015
The combined image, the scientists said, confirms a prediction of such halos made in 1961.
Can anyone here tell me who made this prediction?
See http://arxiv.org/...08.05153
...and just for good measure – http://ptps.oxfor...ent/20/1

Oct 13, 2015
@Protoplasmix: Thank you very much, but I was actually able to find it from my2cts comment. Appreciate the help though!

@my2cts: Ditto, thank you kindly!

Oct 13, 2015
Articles like this help to back up my earlier supposition, in previous articles, about how galaxies can grow, how their black holes can either evaporate partially during a quasar event forming the Fermi Bubbles Tuxford below mentions. But another poster was dismissive that there might be huge galactic magnetic fields, and here we have halos that are most certainly made visible by their galaxy's magnetic fields, and once the central black hole grows even further, and a couple more mergers with other spiral galaxies, in Fusion, to form the fully stellar-realized magnetic bubble.

They are finding evidence of massive magnetic fields, larger than, and passing through huge galactic clusters, like beads on a string, so having a compact (comparatively) field of stars in a galaxy showing that it has a Massive magnetic field.

Are we looking at the fusion of elements just past the Big Bang, from a very sub atomic scale? Should be nearly identical fractilic expressions of each other.

Oct 14, 2015
Hoyle's failure to realize that the creation event could produce any and all elements has come full circle.

I am convinced that Oxygen was created in abundance at the original creation event of the universe, and that partial charge properties of Water is essential for creating objects of transitional masses, since gravity alone acts too slowly in a distributed cloud.

While this halo is actually produced by billions of Supernova explosions throughout the lifetime of the galaxy, with some material escaping and some being captured, some falling into the core again to be taken up by other stars and black holes, etc. I described this process in the past regarding both Globular Clusters and Galaxies, and this is how so much matter migrates to the black hole. I believe this can probably account for as much as 10% of the mass accumulation of some supermassive black holes, since you must remember about half the mass in a SN is directed outward and the other half inward...

Oct 14, 2015
I have also figured out a mechanism whereby most of the mass which is ejected above galactic escape velocity can still be re-captured by the galaxy at a later time. If these gases encounter inter-galactic dust clouds which have certain ranges of velocity, the collision can slow down the gases which originally had too much velocity, and therefore give gravity the opportunity to capture the escaping gases again.

The intergalactic media appears to play an important role in slowing down the expanding cloud.

My initial calculations for the Milky Way sized galaxy suggest this may take around 100 million years for ejecta from a SN to pass through the entire cycle of recapture, depending on it's starting position and it's power level. Also the density of nearby inter-galactic media will be different for every galaxy so you can't really know how much that is contributing for any one galaxy without specific observation, which will require better telescopes.

Oct 14, 2015
Additionally, galaxies which have passed through an AGN phase may have blown away their inter-galactic dust in the nearby vicinity, which may make it easier for additional ejecta to escape during SN explosions. So once again, there will be general rules which apply to all galaxies, but the specific history of each galaxy will be important to how the halo evolves and what it's elemental composition will be.

More massive galaxies will be able to capture a larger percentage of the faster, lighter elements, so their isotopic ratios in the halo will be different than that of less massive galaxies.

Oct 14, 2015
I would like to see a full scale super-computer simulation of these processes, with color-coding for all major types of materials involved. It should use all known physics laws and effects, not just over-simplifications. There may be some physical processes happening which have been over-looked, and which can't be dtected by existing telescopes, or for example happened so far back in the galaxy's history that you can't see it now (such as fully escaped ejecta).

Suggest color codes:

Hypothetical Dark Matter: Violet
Stars: Don't assume age, but track it: instead Color-code by composition. Red, blue, yellow.
Oxygen gas: Green
Hydrogen and Helium gas: White
Molecular Water(gas/dust): Aqua (appropriately)
Other lighter metals (gas/dust): Pink
Heavier metals(gas/dust): Brown

Model the whole galaxy from the beginning of time through about 20 billion years of simulated time (to avoid being biased towards any given age range), and let's figure out EXACTLY how this works.

Oct 14, 2015
A gamma ray halo of the Milky Way galaxy extending far out in the space was observed in 1997 by D. Dixon et al. and explained by a Canadian, A. Malek, in 2003. :http://redshift.v...2MAL.pdf

Oct 16, 2015
Remember, if you fly a starship into it, you might become a god, just like Gary Mitchell.

Oct 17, 2015
A gamma ray halo of the Milky Way galaxy extending far out in the space was observed in 1997 by D. Dixon et al. and explained by a Canadian, A. Malek, in 2003. :http://redshift.v...2MAL.pdf


A very large halo of ordinary matter has been observed around the Andromeda galaxy as well. For the most part, it seems to be pretty evenly distributed, but it's pretty clear any decent sized object or system passing through the halo would be effected by its mass both in terms of gravity and collision (i.e. slowing due to conservation of momentum/angular momentum).

These have been known for a while, but they don't show up in computer model simulations for the most part, and they seem to be largely ignored in discussions of Dark matter and such.

Measurements of the Milky Way's gravitational acceleration by observing a nearby Globular Cluster's evolution discovered MW is much less massive than text books and encyclopedia claims.

Oct 17, 2015


A gamma ray halo of the Milky Way galaxy extending far out in the space was observed in 1997 by D. Dixon et al. and explained by a Canadian, A. Malek, in 2003. :http://redshift.v...2MAL.pdf


A very large halo of ordinary matter has been observed around the Andromeda galaxy as well.


Modern official cosmology is based on mathematical idealism and tautology- the conclusion is contained in the premise! For example: GR assumes that the universe is finite (without any basis), it then follows logically that it has a beginning in a Big Bang and is expanding! In an infinite universe none of these would be possible!

A better (dialectical) approach for an understanding of the galaxies; their formation, evolution, the structures etc. is provided in the article by the same author as above :"Ambartsumian, Arp and the Breeding galaxies": http://redshift.v...2MAL.pdf


Oct 18, 2015
A better (dialectical) approach for an understanding of the galaxies...

An "approach for an understanding" is not better for being dialectical (philosophical), nor by pleasing you. Nor does it debunk other theories, only the conclusive evidence does that. Having any?

Oct 19, 2015
You mean like the conclusive of evidence of DM and BH's?
Nope. I mean like the conclusive evidence required to debunk a specific cosmological theory before claiming it is wrong. I though I put it easy.
Yes one must have conclusive evidence that something which cannot be observed or produced doesn't exist.
Sounds pretty much like what I said. Are you sure you are in disagreement?
Let me add, this is also required for considering something proven too.

Oct 19, 2015
Until it is proven these things DON'T exist...
Excuse me... are you choosing? You can't reach conclusions in such circumstances. That's why research is required and why explanations of phenomena are tipically labeled "theory" and "hypothesis".
...we will assume they do cause math based on our assumptions of how things work says so.

Assumptions are required to carry out test, it doesn't mean things have been considered proven.
http://dictionary...pothesis
Now go find evidence that something we can't see or find doesn't exist....dare ya!

Evidence may be conclusive. Lack of it, is not -> researches continue.

Oct 20, 2015
-> Research should produce a definitive result prior to insertion of a theory into other theories.
Why it should? It's not even subject to criterion. When research throws more unknowns than evidences, the need for more hypotheses arise naturally. It's a consequence of complexity, not a choice.
And, I suppose, when you have definitive results you don't have a theory but an explanation accepted as correct, or a rejected theory.

As far I know the subject of your interest hasn't been granted definitive results ( https://en.wikipe...k_matter ). You may be overreacting to the treatment given to such topics. Perhaps this isn't the kind of site of your liking, simply.

Oct 20, 2015
Theories are required to carry out tests, assumptions no.
That's because the theories itself are what are to be tested. It's assumed that they work as described in order to test them (interpret by assumption a supposition, of course). Then compare the results with the expectations and reach conclusions (whether to verify or falsify): assumption -> test -> results -> conclusion.

The error is to put the assumption in the conclusions rather than the test part. For example:
it doesn't exist until observation and conclusive evidence say otherwise.
The assumption is placed in the conclusion: "it doesn't exist"
If lack the conclusive evidence, then > we don't know <
In such case, that was just a personal opinion. You may not expect these articles to be in agreement with you. Again, perhaps this simply isn't the kind of site of your liking.

Oct 21, 2015
..when you have definitive results you don't have a theory but an explanation accepted as correct, or a rejected theory.
Now you're getting it.
Seems I got it earlier: evidence debunks (rejects) or prove theories (correct), nothing else. Do you?

When research throws more unknowns than evidences, the need for more hypotheses arise
Sometimes, and when they do you validate them prior to moving on and hoping you "guessed" right.
What? There is no straight path to follow. You have to address the unknowns with further hypotheses or get stuck. Validation is the final goal, not the next step.

...and [I] said assumptions should never be a part of a test.
The assumption is part of the hypothesis already. I suppose you heard of "trial and error", for example.
You don't "hope" it works, you check what it does an conlude whether it does or not.

I 'hope' it's you who is getting it now, it's going on circles already.

Oct 22, 2015
Deriving an equation is never a "test" of reality...
Right, it's not a test, but the hypothesis itself.
...it is either an accurate description of a phenomenon or it isn't.
Good. Then you test it (i.e put some numbers on it) and conclude if it's accurate or not.
When math doesn't match observation, this means the math is wrong...it really is that simple whether you like it or not.
Correct. To be precise, this means that at least *something* is wrong on it.
When the mathematical "fix" doesn't match observation, this means the math is still wrong. Get it?
Yup. This happens often, and that's why there is so much work ahead yet.
it's going on circles already.
Are you complaining about it or..?
Complaining of course, conversation going into many circles, don't you think?

Oct 22, 2015
Here is another circle:
When your research presents new unknowns, it's both [about validation]. Otherwise you are adding unknowns into a problem...
These were part of the problem already. You just realized it, due to the test. Whether you study further as a whole or split it by parts, you will create lots of hypotheses (likely crossed) to deal with that. Same story.

I think this is what keep the circles going:
...adding unknowns into a problem and *claiming* you came up with a valid result
There is no claim if these are labeled "theory" and "hypothesis", told you already. This means validations are pending.
You can think, be smart. Don't care on topics treatment made in articles, it's done for easy handling of accepted theories as plausible explanation of facts: http://dictionary...e/theory

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