Little galaxies are big on dark matter

December 30, 2011 by Tammy Plotner, Universe Today

Little galaxies are big on dark matter

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The stellar stream in the halo of the nearby dwarf starburst galaxy NGC 4449 is resolved into its individual starry constituents in this exquisite image taken with the 8.2-meter Subaru Telescope and Suprime-Cam. Image credit: R. Jay GaBany and Aaron J. Romanowsky (UCSC) in collaboration with David Martinez-Delgado (MPIA) and NAOJ. Image processed by R. Jay GaBany

Dark matter... It came into existence at the moment of the Big Bang. Within its confines, galaxies formed and evolved. If you add up all the parts contained within any given galaxy you derive its mass, yet its gravitational effects can only be explained by the presence of this mysterious subatomic particle. It would be easy to believe that the larger the galaxy, the larger the amount of dark matter should be present, but new research shows that isn’t so. Dwarf galaxies have even higher proportions of dark matter than their larger counterparts. Although the dwarfs are the most common of all, we know very little about them -- even when they consume each other. Enter the star stream...

“Several of my previous images feature the fossil remnants of these ancient mergers as faint stellar rivers called tidal streams. These stellar streams are the table crumbs from small dwarf galaxies that were gravitationally dismembered as they were devoured by the larger galaxy they orbited.” says astrophotographer, R. Jay Gabany. “The theory implies dwarf galaxies also merged and are still merging with each other. But, there has never been clear photographic evidence or a close investigation of dwarf galactic mergers until now.”

The target is NGC 4449, a small, irregular dwarf galaxy much like the the Milky Way’s Large Magellanic Cloud. What makes it interesting to astronomers is the presence of thousands of hot blue stars and massive red regions interspaced with thick dust clouds. It isn’t just forming new stars… it’s experiencing an explosion of star birth! According to current theory, dwarf galaxies such as this one could be undergoing a merger event, but there hasn’t been photographic proof until now.

“The picture I am sharing is of a small, dwarf galaxy known as NGC 4449 that’s located about 12.5 million light years from Earth towards the northern constellation of Canes Venatici, the Hunting Dogs. This galaxy is about the size of our Milky Way’s largest satellite galaxy, the Magellanic Cloud. But, NGC 4449 is much farther away and it is experiencing a major star burst event- an episode characterized by the production of new stars at a furious rate.” says Gabany. “This image is unique because is it captures the first dwarf galaxy known to have its own tidal stream of stars. Therefore, it represents the first closely studied example of a merging with an even smaller dwarf star system! The professional astronomers with whom I work also suspect the merger may have contributed to the ferocious production rate of new stars inside NGC 4449.”

The research done by the team led by Dr. David Martinez-Delgado has some very interesting ramifications and their paper has been accepted for publication in the Astrophysical Journal Letters.. As so well put in Jay’s photographic explanation in his webpage; “Although the cold dark matter theory predicts mergers and interactions between dwarf galaxies, there is scant observational evidence that these types of mergers are still happening in the nearby local Universe. Interactions between dwarf galaxies invoke the possibility of exploring a very different merger regime. For example, research has shown that multiple dwarf with different stellar masses may exist in similar sized dark matter halos, hence what appears as a minor merger of stars could be a major dark matter merger. Studying interactions on a small scale, such as NGC 4449, provides unique insights on the role of stars versus in galactic merger events.”

Where once amateur astrophotographers painted beautiful portraits of what lay just beyond human perception in deep space, they are now crafting images capable of true science. The eyes of their telescopes are being combined with professional instruments and producing amazing results.

“We live in an age where science has become unfettered from examining the Universe with only our physical six senses.” concludes Gabany. “This has unlocked a profound new level of understanding, resolved ancient mysteries and unlatched a Pandora’s chest filled with new questions begging for answers. We still have much to learn.”

More information: For Further Reading: Dwarfs Gobbling Dwarfs: A Stellar Tidal Stream Around NGC 4449 and Hierarchical Galaxy Formation On Small Scales and The Big Deal About Dwarf Galaxies.

Provided by Universe Today

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rawa1
Dec 30, 2011

Rank: 1.3 / 5 (13)
In dense aether model the gravity field arises from shielding of superluminal gravitational waves with massive objects, so it's bound to the presence of massive objects in deterministic way - you cannot have a gravity without some massive object nearby. But the same shielding mechanism can be applied for explanation of forces between other massive bodies. In AWT the cold dark matter is the result of gravitational waves shielding with all massive objects at the same moment. Because the observable objects have no regular distribution, it can leads to the shadows of gravity shadows, i.e. into pockets of dark matter which have no apparent connection to the visible matter (so called the dark galaxies), which contain a lot of dark matter, but nearly none visible matter. And vice versa, the massive objects surrounded with many other have significantly lowered the content of dark matter (typically the objects at the center of galaxies).
rawa1
Dec 30, 2011

Rank: 1.4 / 5 (11)
Now just try to imagine, how the mutual shielding of forces is working. Every massive objects tends to collect the other objects from its close neighbourhood because of gravity. It leads into inhomogeneity of matter distribution - such compacted objects are surrounded with large area of empty cosmic space, where the shielding of another massive objects from the whole Universe may apply. It leads into increased concentration of dark matter here, which gradually fills the free space between massive objects. At the moment, when certain threshold of dark matter density is reached (as expressed with Schwarzchild criterion), the dark matter starts to condense into heavier particles in process, which corresponds the nucleosynthesis of baryons in Big Bang Universe model. The observable matter regenerates itself from vacuum at the free places between collapsed matter in similar way, like the clouds on the sky, which are condensing from seamlessly empty space.
rawa1
Dec 30, 2011

Rank: 1.4 / 5 (10)
In the dense aether model the galaxies are condensing and evaporating randomly like giant fluctuations of dense gas or like the clouds on the sky. The galaxies are gradually evaporating their mass into energy, until very tiny and sparse black holes remain. These tiny remnants never evaporate completely though. Just before the last remnants evaporate, the concentration of dark matter increases around them up to level, which ignites the formation of new generation of matter. In this way, the matter is recycling gradually. Note that the remnants of previous generation serve here as a seeds, which can make the principle of cosmological natural selection relevant.

http://faculty.ar...olin.pdf

IMO this evolution is of antropocentric origin and it doesn't really happen inside of random Universe. But the observable Universe should comprehend it, or it wouldn't be observable just with us, human creatures.
Shelgeyr
Dec 30, 2011

Rank: 2.5 / 5 (11)
Little galaxies are big on dark matter


Translation: Little galaxies fit the Standard Model even less than other galaxies (which, in turn, don't fit either).

...yet its gravitational effects can only be explained by the presence of this mysterious subatomic particle.


There's that "can only be explained by..." again.

The phrase should actually read more along the lines of "...yet its gravitational effects can only be explained by these particular scientists operating within the limits of their knowledge and/or scientific dogma by the presence of this mysterious subatomic particle."

These people apparently have lost all understanding of "falsification", to the point where the greater the disparity between observable reality and theory, the greater the assumed presence of "dark matter", as opposed to recognizing that the theory - the Standard Model - is broken and has been falsified.
yyz
Dec 30, 2011

Rank: 4.5 / 5 (8)
Around the time the paper describing observations of this stellar stream were published another paper appeared detailing a possible second dwarf galaxy cannabalized by NGC 4449. In this case, a globular cluster in the galaxy appears flattened and displays two short tails of stars on either side of the cluster, similar to some gravitationally distorted globular clusters in the Milky Way. These and other clues point to this cluster being the surviving nucleus of a dwarf galaxy almost totally consumed by NGC 4449: http://arxiv.org/...61v1.pdf

One point mentioned in the paper on this stellar stream ( http://arxiv.org/...54v1.pdf ) is that mass estimates from the light of the galaxy and stream are about 20:1, considered minor merger. When dark matter is considered though, the mass estimate may be as high as 3:1, making this a major merger (in disguise).
yyz
Dec 30, 2011

Rank: 5 / 5 (5)
Amateur astronomer Jay GaBany, who acquired the deep 0.5m telescope images for this study also features the fantastic 8-meter Subaru image of NGC 4449 on his website (worth a look!): http://www.cosmot...449.html

The globular cluster CL 77, thought to be the nucleus of a second dwarf galaxy consumed by NGC 4449 (see my previous post) is also visible in this Subaru image.
rawa1
Dec 30, 2011

Rank: 1.4 / 5 (9)
These people apparently have lost all understanding of "falsification"
It's result of specialization in science. It's probable, Einstein would never find general relativity, if he would measure the Mercury precession himself. The astronomers, capable of such difficult observations aren't usually the best theorists and vice-versa. They're not required to explain all effects, which they understand.

In addition, the anomaly in space-time curvature can be always modelled with particle field, which are so tiny, they penetrate massive bodies freely. For example, the Lens-Thirring effect is routinely interpreted with space-time curvature in general relativity, but it could be interpreted like dragging of cloud of neutrinos surrounding the massive bodies. And vice-versa, every particle can be interpreted like the product of spontaneous symmetry breaking of space-time due the limited speed of light.
MorituriMax
Dec 30, 2011

Rank: 4.2 / 5 (10)
dense aether blah blah blah...
TheWalrus
Dec 30, 2011

Rank: 3.2 / 5 (9)
Translation of the above comments (except yyz's): "Everyone but me is a clueless, arrogant crackpot."

Thanks for being so self-unaware, guys. You're why I read the comments. And Oliver: Get help. Seriously.
theon
Dec 30, 2011

Rank: 2.6 / 5 (5)
And still people are told to believe that elementary particles will do this dark matter job. Despite all the counter evidence.
Callippo
Dec 30, 2011

Rank: 1.6 / 5 (9)
Everyone but me is a clueless, arrogant crackpot.
I've just a model and I'm interpreting the observation in context of that model. No less, no more. Nobody prohibits you in interpretation of these data with L-CDM model, but I'm afraid, Shelgeyr has summarized it already. The fact, people have their own opinion doesn't mean, they're Antichrists, it just means, they've their free will. Now you can return to your reddit and censor the people from there.
Anda
Dec 30, 2011

Rank: 4 / 5 (5)
Amateur astronomer Jay GaBany, who acquired the deep 0.5m telescope images for this study also features the fantastic 8-meter Subaru image of NGC 4449 on his website (worth a look!): http://www.cosmot...449.html

The globular cluster CL 77, thought to be the nucleus of a second dwarf galaxy consumed by NGC 4449 (see my previous post) is also visible in this Subaru image.


Thanks for the link yyz.
Anda
Dec 30, 2011

Rank: 3.7 / 5 (3)
Everyone but me is a clueless, arrogant crackpot.
return to your reddit and censor the people from there.

As you say, clueless arrogant crackpot aether brain master...
jsdarkdestruction
Dec 31, 2011

Rank: 4.3 / 5 (6)
Everyone but me is a clueless, arrogant crackpot.
I've just a model and I'm interpreting the observation in context of that model. No less, no more. Nobody prohibits you in interpretation of these data with L-CDM model, but I'm afraid, Shelgeyr has summarized it already. The fact, people have their own opinion doesn't mean, they're Antichrists, it just means, they've their free will. Now you can return to your reddit and censor the people from there.

a model you spam all over the site just like oliver does with his, you ar no better than him. in fact i'd say you are worse.
rawa1
Dec 31, 2011

Rank: 1 / 5 (2)
This is your last ten comments
who in their right mind would pay $1 for that book? answer-no one, it wouldnt even make good toilet paper. oliver needs to stop spamming advertisements for his incredibley overpriced garbage book.
the republicans are going to go crazy over this. poor big oil, always being picked on....
I am well aware of the current definition and was commenting on how we need to fix it as its ridiculous to say a 3 foot chunk of rock is a moon.
your aether wave theory posts are all spam just like olivers, what is so hard to understand about that?
Neutron repulsion doesnt exist anymore than santa claus does oliver. It's a fantasy thats outlived its time. Just give it up already, you wasted your career.
Oliver, do you not know of phase 2 of the plan? ...
Oliver, do you not know of phase 2 of the plan? ...
Just try to imagine the result, if everyone would post the same OT blurbs, like you...
jsdarkdestruction
Jan 01, 2012

Rank: 4 / 5 (4)
if oliver wouldnt spam attacking scientists first i would do nothing. I already explained how i refuse to watch him attack the scientific community over and over again like he does when in fact he is the one not to be believed or trusted.
Callippo
Jan 01, 2012

Rank: 1 / 5 (2)
In this thread I explained, how particles of antimatter correspond the opponents of mainstream opinion and why they concentrate around massive objects in clouds of dark matter in similar way, like the dissidents focus to to the proponents of mainstream opinion. These opponents tend to concentrate to boundary and isolated problems of mainstream ideology, because it can be attacked most easily from there. In this analogy, the particles of dark matter prefer smaller isolated objects and boundary of larger galaxies, so their relative concentration is higher there.

http://www.physor...ter.html
signoftimes
Jan 01, 2012

Rank: not rated yet
Everyone but me is a clueless, arrogant crackpot.
I've just a model and I'm interpreting the observation in context of that model. No less, no more. Nobody prohibits you in interpretation of these data with L-CDM model, but I'm afraid, Shelgeyr has summarized it already. The fact, people have their own opinion doesn't mean, they're Antichrists, it just means, they've their free will. Now you can return to your reddit and censor the people from there.


Much like going to a math teacher with the wrong answer and claiming you are right by way of creativity. What you and omatumr are doing is exactly that.

http://www.biblio...ol01.htm
Callippo
Jan 01, 2012

Rank: 1 / 5 (3)
Much like going to a math teacher with the wrong answer
The absence of math doesn't mean, the claim is wrong. Does your mum use the math for reasoning of her opinion? And I'm not promoting some particular hypothesis here like omatumr. I'm just trying to explain things with using of analogies.
Callippo
Jan 01, 2012

Rank: 1 / 5 (2)
BTW The fact, small galaxies contain larger amount of dark matter violates most of formal models, which I know (MOND, TeVeS, STVG, MOG, etc..). All these models consider the dark matter as a byproduct of gravity field of massive body, i.e. the mass of object itself. The higher mass of this body is, the more intensive its dark matter effects should be too.
In dense aether theory the dark matter is the product of gravity shielding with neighboring matter instead, i.e. it's not only the function of the mass of galaxy, but the function of the mass and distance of all surrounding galaxies too. This is fundamental difference, as it points to the insight, we cannot analyze the dark matter effects of massive objects separately from their environment. If you don't realize it, then you never can derive the correct model, because you would have only part of problem on mind. It means, you should understand the problem at its intuitive level before starting the derivation of formal solution of it
signoftimes
Jan 01, 2012

Rank: 5 / 5 (3)
Much like going to a math teacher with the wrong answer
The absence of math doesn't mean, the claim is wrong. Does your mum use the math for reasoning of her opinion? And I'm not promoting some particular hypothesis here like omatumr. I'm just trying to explain things with using of analogies.


My point was harsh but intended to differentiate logic and fantastic thought. When the theory is proven wrong from multiple sources and for multiple reasons, it is pointless and perhaps irresponsible to continue to promote. Not trying to stifle thought, just trying to promote logic. And at times I see too much wasted effort and misdirection from educated, intelligent people. If that is what one wants to do, become a journalist, not a scientist.
Callippo
Jan 01, 2012

Rank: 1 / 5 (3)
When the theory is proven wrong from multiple sources and for multiple reasons
Which theory? The dense aether model was proposed with Oliver Lodge. It was never refused, proved wrong the less.
hard2grep
Jan 02, 2012

Rank: 3.7 / 5 (3)
According to Einstein, energy is equivalent to mass. Has any group of scientists period taken into account the amount of mass that is imparted by plain energy like photons or thermal values and emissions. All things considered, I have yet to see the labor involved in what the actual effect regular light emissions have on the overall gravity well of objects in which they reside... I would love to see an article that shows me this particular information, since we are guessing about something we have never seen. why not remove all possible variables before jumping over a cliff?

I wonder why the universe isn't unbearably bright right now? Where do virtual particles come from?
I sure have questions...
rawa1
Jan 02, 2012

Rank: 1 / 5 (1)
Has any group of scientists period taken into account the amount of mass that is imparted by plain energy like photons or thermal values and emissions.
Yes, but the mass of photons and neutrinos contributes only slightly to the current mass of Universe (up to 5% both). IMO this number is substantially higher, but the peer-reviewed estimations from Big Bang are here.

http://scienceblo...tent.png

Rank 4 /5 (8 votes)
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