Surprising clutch of hydrogen clouds discovered lurking among our galactic neighbors

May 08, 2013
This combined graphic shows new, high-resolution GBT imaging (in box) of recently discovered hydrogen clouds between M31 (upper right) and M33 (bottom left). Credit: Bill Saxton, NRAO/AUI/NSF

(Phys.org) —In a dark, starless patch of intergalactic space, astronomers have discovered a never-before-seen cluster of hydrogen clouds strewn between two nearby galaxies, Andromeda (M31) and Triangulum (M33). The researchers speculate that these rarefied blobs of gas—each about as massive as a dwarf galaxy—condensed out of a vast and as-yet undetected reservoir of hot, ionized gas, which could have accompanied an otherwise invisible band of dark matter.

The astronomers detected these objects using the National Science Foundation's Green Bank Telescope (GBT) at the (NRAO) in Green Bank, W.Va. The results were published in the journal Nature.

"We have known for some time that many seemingly empty stretches of the Universe contain vast but diffuse patches of hot, ionized ," said Spencer Wolfe of West Virginia University in Morgantown. "Earlier observations of the area between M31 and M33 suggested the presence of colder, neutral hydrogen, but we couldn't see any details to determine if it had a definitive structure or represented a new type of cosmic feature. Now, with high-resolution images from the GBT, we were able to detect discrete concentrations of neutral hydrogen emerging out of what was thought to be a mainly featureless field of gas."

Astronomers are able to observe neutral , which is referred to as HI (H and the Roman numeral one), because of the characteristic signal it emits at , which can be detected by on Earth. Though this material is abundant throughout the cosmos, in the space between galaxies it can be very tenuous and the faint signal it emits can be extremely difficult to detect.


The animation demonstrates the difference in resolution from the original Westerbork Radio Telescope data (Braun & Thilker, 2004) and the finer resolution imaging of GBT, which revealed the hydrogen clouds between M31 and M33. Credit: Bill Saxton, NRAO/AUI/NSF.

A little more than a decade ago, astronomers had the first speculative hints that a previously unrecognized reservoir of hydrogen lay between M31 and M33. The signal from this gas, however, was too faint to draw any firm conclusions about its nature, origin, or even certain existence. Last year, preliminary data taken with the GBT confirmed that there was indeed , and a lot of it, smeared out between the galaxies. These preliminary observations, however, lacked the necessary sensitivity to see any fine-grain structure in the gas or deduce whence it came and what it signified. The most likely explanation at the time was that a few billion years earlier, these two galaxies had a close encounter and the resulting gravitational perturbations pulled off some wispy puffs of gas, leaving a tenuous bridge between the two.

New and more thorough studies of this region with the GBT, however, revealed that the hydrogen gas was not simply in the form of wispy streamers, as would be expected by the interactions of two galaxies in a gravitational ballet. Instead, a full 50 percent of the gas was conspicuously clumped together into very discrete and very massive blobs that—apart for their lack of stars—would be dead ringers for dwarf galaxies. Dwarf galaxies, as their name implies, are relatively small collections of stars bound together by gravity. They can contain anywhere from a few thousand to a few million stars.

The GBT was also able to track the motion of these newly discovered clouds, showing that they were traveling through space at velocities similar to M31 and M33. "These observations suggest that they are independent entities and not the far-flung suburbs of either galaxy," said Felix J. Lockman, an astronomer at the NRAO in Green Bank. "Their clustered orientation is equally compelling and may be the result of a filament of dark matter. The speculation is that a dark-matter filament, if it exists, could provide the gravitational scaffolding upon which clouds could condense from a surrounding field of hot gas."

The researchers also speculate that these clouds may represent a new and previously unrecognized source of neutral hydrogen gas that could eventually fall into M31 and M33, fueling future generations of star formation.

The GBT, because of its enormous size, unique design, and location in the National Radio Quiet Zone of West Virginia, was able to detect this signal, which was simply too faint for other radio telescopes to detect with precision. "The GBT is unique in this regard," said Lockman.

Astronomers are also interested in these cold, dark regions between galaxies because there is a great deal of unaccounted-for normal matter in the cosmos, and a significant fraction may be contained in intergalactic clouds like the ones observed by the GBT. Further studies in this region and around other galaxies in our Local Group (the galaxies found relatively close to the Milky Way) may yield additional clues as to the amount of hydrogen yet to be accounted for in the Universe.

"The region we have studied is only a fraction of the area around M31 reported to have diffuse hydrogen gas," said D.J. Pisano of West Virginia University. "The clouds observed here may be just the tip of a larger population out there waiting to be discovered."

Explore further: Millisecond pulsars clearly demonstrate that pulsars are neutron stars

More information: dx.doi.org/10.1038/nature12082

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cantdrive85
1.3 / 5 (13) May 08, 2013
The speculation is that a dark-matter filament, if it exists, could provide the gravitational scaffolding upon which clouds could condense from a surrounding field of hot gas.


Of course that's the speculation, they don't have a clue as to how plasma behaves, how it self organizes, ionizes surrounding material, and how filamentation is totally EXPECTED for such phenomenon. Mysteries will remain mysteries if the inappropriate application of gas laws continues in the description of this plasma. It should also be noted, this filamentary bridge is expected in Plasma Cosmology, it is these galactic size Birkeland currents which pinch to create galaxies. In PC, galaxies and stars reside along these Birkeland currents like "beads on a string", a closed circuit is necessary for the electricity of the Cosmos to flow.

yyz
4.8 / 5 (6) May 08, 2013
This new study builds on previous observations of the "bridge" between the two galaxies as reported here last year: http://phys.org/n...tml#nRlv

Details of those initial observations appeared in a paper by Lockman et. al. submitted to the Astronomical Journal (and here): http://arxiv.org/abs/1205.5235
barakn
3.4 / 5 (5) May 09, 2013

Of course that's the speculation, they don't have a clue as to how plasma behaves, how it self organizes, ionizes surrounding material, and how filamentation is totally EXPECTED for such phenomenon.

Did you even bother to read the article or look at the pictures? The hydrogen clouds themselves are not filamentary - the article goes out of its way to point out they are not in the shape of wispy streamers and calls them "discrete and massive blobs". What was being called filamentary was the invisible dark matter, the wire upon which the hydrogen cloud beads are strung. Since you don't believe in dark matter, that means there's absolutely nothing filamentary in this region whatsoever, and therefore your mention of filamentation and Birkeland currents is completely spurious. Good luck explaining a bunch of isolated blobs.
GSwift7
4.4 / 5 (8) May 09, 2013
they don't have a clue as to how plasma behaves


Yes they do, but this is neutral hydrogen.

and how filamentation is totally EXPECTED for such phenomenon


These aren't filaments, they are blobs.

continues in the description of this plasma


Once again, it's cold neutral hydrogen.

this filamentary bridge is expected


Once again it's not a filament, and the new image shows that it's not a bridge.

it is these galactic size Birkeland currents


Once again, neutral, not charged. No current possible.

a closed circuit is necessary for the electricity of the Cosmos to flow


Huh?
cantdrive85
1.6 / 5 (5) May 09, 2013
Let's read it again then...
The researchers speculate that these rarefied blobs of gas—each about as massive as a dwarf galaxy—condensed out of a vast and as-yet undetected reservoir of hot, ionized gas,

It condensed out of ionized gas...

I chose to click on the link for further reading, and in that preview there is this sentence;

This feature has been interpreted to be the neutral component of a condensing intergalactic filament.


So they confirm the filamentary morphology. Now if we take Gerrit Verschuur's extensive work on "neutral" HI clouds we know that this PARTIALLY ionized plasma still has magnetic fields (causing filaments) and many other properties of plasma.

http://www.plasma...007b.pdf

http://www.plasma...tAsJ.pdf

http://www.plasma...2000.pdf

Once again, seeing the Universe through myopic lenses.

HannesAlfven
1.8 / 5 (5) May 09, 2013
Astrophysics is not all it seems to be. Gerrit Verschuur is a great case in point. In order to get his papers published in the Astrophysical Journal, Verschuur has to go out of his way to use the word "neutral" when explaining his observations of HI hydrogen. But, anybody who reads Verschuur's The Invisible Universe will notice all sorts of warnings towards the front of the book about astrophysicists' problematic historical treatment of cosmic radio waves. And a close look at his short chapter on the "anomalous high-velocity clouds", in combination with his numerous papers on critical ionization velocities associated with knots observed within HI filaments, suggest that Verschuur is simply using the proper astrophysical buzzwords in order to bypass the peer review gatekeeping.
HannesAlfven
1.8 / 5 (5) May 09, 2013
What is either comical (or sad?) is that it seems that most astrophysicists are probably not even aware that there exists a second, electrical explanation for the "neutral" HI filaments based upon a line of argumentation and evidence which stretches back more than a half century. Yes, we can disagree over what the HI even represents, and we should definitely do that! But, the problem for the astrophysical community is that if you confine that conversation to the box of the conventional worldview in physics, you stop the more meaningful debates before they even get started.

The funny/sad part is that the conversation amongst astrophysicists is never motivated to get to that more interesting stage, because they have decided to ostracize anybody who questions the very delicate structure which they've invested bi(tri?)llions constructing. Their decision to focus exclusively upon one cosmology forces them to defend it, regardless of the evidence, in order to simply save face.
HannesAlfven
2.3 / 5 (6) May 09, 2013
What the public is taking its sweet time realizing is that the culture of our scientific disciplines exerts an incredible effect upon the ways in which ALL of these papers are being written. The public's confusion on where the real controversies are in science - as well as the widespread belief that no serious challenges even exist - naturally follows from this shell game.

What's particularly ironic with the conversations we see here attached to this article is the insistence that dark cosmic plasma (plasma that is not in the glow or arc modes) is somehow fraudulent science, whereas dark matter is the real thing. It's interesting to watch mainstreamers point to the superiority of an old unconfirmed hypothesis over a laboratory inference based upon actual experimentation.

But, what nobody seems to mention is that the culture of astrophysics simply makes us all that much more ignorant of competing models and claims, and dependent upon the authority of the astrophysicists themselves.
no fate
1 / 5 (2) May 09, 2013
The funny/sad part is that the conversation amongst astrophysicists is never motivated to get to that more interesting stage, because they have decided to ostracize anybody who questions the very delicate structure which they've invested bi(tri?)llions constructing. Their decision to focus exclusively upon one cosmology forces them to defend it, regardless of the evidence, in order to simply save face.


Accurate assessment, but not all can be judged this way. People who parrot mainstream physics on forums and news sites like this are a dime a dozen. Some do it well but appear to be open to discussion, some also do it well but are as you state above, some should just stick to rating. In the exchanges here it appears mostly as you state above but this is why they are posting here. Nobody engaged in groundbreaking work would have time for this site or any other unless they are curious about a paper they have done that is featured here.
yyz
5 / 5 (5) May 09, 2013
A preprint of the paper in Nature has now been posted on arXiv: http://arxiv.org/abs/1305.1631

These clouds have typical HI masses of 1-4x10^5 Msun and diameters of 1-6kpc (similar to typical low luminosity dwarf galaxies, but with no stars). If more examples of these starless systems exist they may help to explain some of the missing (baryonic) mass seen wrt M31 and the Milky Way.

"....filamentation is totally EXPECTED for such phenomenon."

According to EU guru Anthony Peratt's model, ALL galaxies are connected by filamentary Birkeland currents that average 350 Mpc in length and should be easily detected by COBE, WMAP and Planck. At the distance of M31, this filament should appear 180 degrees across, stretching from horizon to horizon across the sky! Of course, no filaments are visible here or in the nearby Virgo Cluster: http://dealingwithcreationisminastronomy.blogspot.com/2009/06/scott-rebuttal-ii-peratt-galaxy-model.html

Observations clearly disprove this model.

cantdrive85
1 / 5 (3) May 09, 2013
Why do you suggest they should be easily visible? Gerrit Verschuur has also done some excellent work in regards to the WMAP. If he is correct about his assertion that the data is much more localized and matches nearby HI clouds then your claim would be incorrect and there's a Nobel prize floating around out there that will need to be voided. Can you win a Nobel based on false knowledge? Apparently.
http://www.wired....big_bang
yyz
5 / 5 (5) May 09, 2013
"Why do you suggest they should be easily visible?"

From my link:

"Peratt's model clearly requires synchrotron emission from the current streams powering the galaxies and his own calculations show that instruments such as COBE and WMAP have sufficient sensitivity to see them."

"...these [intergalactic] Birkeland currents will be expected to emit synchrotron radiation. Dr. Peratt calculated just how much they would be expected to radiate and obtained values of energy output on the same order of magnitude as the measured flux of the cosmic microwave background radiation."

"Peratt own calculations demonstrated that the flux from these currents was comparable to the intensity of the cosmic microwave background radiation and he even expected to see a ''"spaghetti" of radiating filaments surrounding the viewer.'"

So again, where are these intergalactic Birkeland currents that Peratt hypothesizes?

[links to Peratt's work, where available, are at the bottom of the article]
yyz
5 / 5 (4) May 09, 2013
In addition, Peratt's supercomputer simulations modeled currents driven by 30 keV electrons, which is more than sufficient to ionize intergalactic HI. Recombination would result in the emission of EUV photons (@13.6 eV) along these supposed filaments. Studies of Local Group galaxies M31 and M33 as well as the Virgo Cluster show no filamentary structures between galaxies at EUV wavelengths. The non-detection of these Birkeland currents (at several wavelengths) is only one of many problems with Peratt's model.
cantdrive85
2 / 5 (3) May 09, 2013
Is this the structure you were referring?

http://www.nature..._F1.html
cantdrive85
1 / 5 (2) May 09, 2013
This is a good example of the misapplication of physics by the crankpot at dealingwith... Recombination in this environment is theorized by astrofizzlcists ignoring laboratory results.

Peratt's supercomputer simulations modeled currents driven by 30 keV electrons, which is more than sufficient to ionize intergalactic HI.


And that exactly what Verschuur found in the paper linked above, only with the correct physics being considered.

"...these [intergalactic] Birkeland currents will be expected to emit synchrotron radiation. Dr. Peratt calculated just how much they would be expected to radiate and obtained values of energy output on the same order of magnitude as the measured flux of the cosmic microwave background radiation."


Also what Vershuur found, but the data coincidentally matched the local filamentary structure of the Milky Way. As the article linked above suggests, astrofizzlcists may be interpreting the smudges on the window for clouds on the horizon.