How Dark Matter Messes with Our Galaxy [Video]

One mystery solves another: dark matter explains the puzzling shape and environs of the Milky Way














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Image: Illustration by Don Dixon

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This video shows the spiral shape of our galaxy and two of its small satellite galaxies, the Large and Small Magellanic Clouds (to the left). The satellites orbit the main galaxy and, in the process, trigger slow-motion waves in it. On a human time scale, those waves look like a static warp in the galactic outskirts. The strange thing is that the satellites are too lightweight to have such a dramatic effect. Astronomers recently demonstrated that their gravity is greatly amplified by dark matter (which this video does not show -- it is, after all, dark).

 

The Magellanic Clouds are not the only satellites of the Milky Way. Astronomers have counted some two dozen. This video shows their three- dimensional position relative to the plane of the galaxy, where the sun and most other stars lie. Here, the mystery is why there are not more satellites: by rights, our galaxy should have hundreds. The Sloan Digital Sky Survey, which scanned the region shown by the pinkish cone, partially filled in the gap by finding another dozen satellites. They are extremely dim and composed mostly of dark matter. The rest of the satellites out there may be completely invisible.

 


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  1. 1. farmeral1980 01:12 PM 9/20/11

    Looks like centrifugal force, like spinning a bicycle wheel and trying to rotate it against its gyro force creating effects similar to what I see in this video, our neighbours are pulling this galaxy but with great force due to combined gravimetric force whether it be from a billion stars or dark matter or any combo from them pulling a rotating disk is going to cause this gyroscopic rotational side force( my words may not be the most descriptive but I think I'm getting my view across). and i think dark matter will be figured out once gravity is whitch i think is like this : earth is like a bubble in the water and is being pressed in from the outside not pulling in from inside.

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  2. 2. jtdwyer 02:11 PM 9/20/11

    There's a lot of unstated prior conclusions / assumptions not stated here, but one of the fundamental problems in evaluating galactic gravitational effects lies in the estimation of their mass.

    Most often galactic mass is estimated from its apparent luminosity. The is an excellent method of deriving the mass of main-sequence stars, as their emission luminosity is a direct function of their mass.

    However, galaxies contain varying amounts of non-luminous, even obscuring masses. In addition, observers within the Solar system have a very specific perspective of any galaxies viewing aspect. A spiral galaxy viewed edge-on, for example, will appear much 'darker' than it would if viewed full-on.

    I'm exceedingly skeptical that it can be decisively determined that the newly discovered, small, "extremely dim" satellite galaxies are composed mostly of dark matter...

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  3. 3. jtdwyer 03:26 PM 9/20/11

    These animations of simulation results do not appear to illustrate any gravitational effects imparted to the visible galactic matter's motions by the presumed dark matter halo. As I understand, the visible diameter of the Milky Way is thought to be about 100,000 light years - the radius would of course be 50,000 light years. As I understand, the Milky Way's dark matter halo is thought to be confined to between about 100,000 light years an 300,000 light years away from the galactic center. If this is correct, it would seem that these satellite galaxies moving within the dark matter halo would primarily be gravitationally influenced primarily by the dark matter halo, thought to be 5-10 times more massive than the visible galactic matter. However, the motions of these satellite galaxies appear to be primarily determined by the visible galactic matter.

    I'd have hoped that the presumed dark matter halo and its motions would be illustrated by an enormous blue cloud... Otherwise, how is the viewer to be able to reasonably understand the effects being attributed to dark matter?

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  4. 4. Dov Henis 05:24 AM 9/21/11

    LHC Chases Its Tail

    An LHC thinking break is required in the 20th/21st-centuries Technology Culture maze rat race.
    (Nov 25 2009)

    A. Main purposes of the LHC (its first high-energy collisions to be attempted early 2010)

    Expected to address most fundamental questions of physics, that are said to block further progress in understanding the cosmic evolution. Planned-built with intention of testing predictions of high-energy physics, mainly:

    - Existence of the hypothesized Higgs boson(s), for completing the Standard Model, to explain the “origin of mass” in the universe,
    - Do all known particles have supersymmetric partners, for clearing up the “mystery of dark matter”,
    - Are there extra dimensions as postulated by models inspired by string theory.

    B. Let's get off the 20th/21st centuries technology culture maze rat race, and take a thinking break:

    The study of cosmic evolution concerns and affects the study and comprehension of each and every subject in the universe. Cosmic evolution originated with gravity, which originated with singularity which was ALL the mass of the universe, and with inflation which was the start of the since then ongoing reconversion of mass to energy.

    Progress in understanding the cosmic evolution starts with Thinking. Every experiment on the course of its study starts with Thinking. Per my thinking (small t, of course)
    E=Total[m(1 + D)] represents the essence of cosmic evolution.

    E = Energy content of the universe, was all in mass format at singularity, when D was 0 for 10^-35 seconds.
    m = mass content of the universe, was ALL the mass of the universe 10^-35 seconds, reconverting to E (as mD) since the Big Bang, driving the galaxies clusters apart since then, increasing D fueled by decreasing m.
    D = total distance of mass travel in all spatial directions, from the point of Big-Bang, of singularity's energy-mass superposition.

    E of the universe is constant, and the variables of E are the extents of its mass formats and their density in the universe. This is the archetype of configuration for the origin of mass. Production of an amount of m in a one-shot process takes an amount of E that renders D zero. In a one-shot process a superduper squeeze to overcome D is required to achieve an E-m superposition. This is to be attempted at the LHC, with the highest amount of energy now feasible for humanity, which may be a diminutively minuscule amount for the purpose.

    Cosmic evolution is the archetype of quantum mechanics in physics, of biological evolution which is the quantum mechanics of biology, of the evolution of every process. All evolutions are E/m processes, strivings to postpone the ongoing reconversion of mass into energy.

    The LHC high-energy collisions will most probably advance our comprehension of it even if, as I expect, it will fail to demonstrate that the origin of mass in the universe depends on the hypothesized Higgs boson(s) that do not exist and will fail to demonstrate the existence of dark matter or dark energy that do not exist as per the above EmD relationship. I avoid the "extra dimensions" since they are beyond my simple-minded comprehension. IMO they are religious concepts. Per my commonsensical scientific concept of cosmic evolution everything started with The Inflation and will eventually, when nearly all mass-fuel is depleted and expansion is overcome by gravity, revert back to singularity and …..

    Dov Henis
    (comments from 22nd century)
    http://universe-life.com/

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  5. 5. jgrosay 10:06 AM 9/24/11

    It seems that a consensus exists about an ever expanding universe. Can this change to a zero start zero end universe depending on how much dark matter is detected as existing ?. Anyway, some say nothing can be compressed below the strings size. A british astronomer, don't remember the name, proposed decades ago an expanding then contracting universe.

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  6. 6. Asobel` 09:18 PM 9/25/11

    How do we know the shape and dimensions of our galaxy?

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  7. 7. Asobel` 09:19 PM 9/25/11

    How do we know the shape and dimensions of our galaxy?

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  8. 8. Dr. Strangelove in reply to jtdwyer 10:23 PM 9/25/11

    Strange that you have no trouble accepting that galaxies contain "non-luminous masses" yet could not accept dark matter. Dark is non-luminous. Your non-luminous masses do not emit not just light but other radiations as well. If they do, astronomers would have detected it already. What's the difference between your non-luminous masses and dark matter?

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  9. 9. R.Blakely 06:33 AM 9/29/11

    Photons can orbit black holes. The mass of these photons is zero, but the photons have gravity. This means that the photons act like dark matter.
    Neutrinos act similarly. But neutrinos can move slower than light speed, and faster than light speed, which means that they can escape black holes. Neutrinos and photons in orbit around stars, act like dark matter because they exert gravity. They are invisible, which means they are dark.

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  10. 10. profchuck 10:22 PM 9/30/11

    Are there any estimates of the effective density of the dark matter clusters? For example, interstellar space contains on the order of two or three hydrogen atoms per cubic meter, from this the mass contained in a large volume of space may be estimated. Can similar estimates be made of the density of dark matter based on the gravitational influence? Also, do polarization studies of light or radio waves passing through suspected dark matter show any signs of bi-refringence or relativistic effects?

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  11. 11. ktperera 09:25 AM 10/3/11

    The secret of dark stuff is in the MOND equations, explain MOND and discover the new gravity.
    http://cosmicdarkmatter.com/Newtonian_Dynamics.html

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  12. 12. IRAFail 05:10 PM 10/8/11

    The double slit experiment makes me want to believe in an atomic conscious. No formula accounts for this and yet all mass that is visible can be affected by it. Like binary, 0 can be observed photon and 1 can be unobserved. The fact we view it with a telescope means it was hit with a photon and it acts a certain way. The fact dark matter is pulling on this or that doesn't mean it's dark it only means no photons are hitting it. The dark matter may behave like regular matter if only photons hit it.

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  13. 13. Dov Henis 11:38 AM 12/8/11

    Dark matter, energy...?

    An Embarrassingly Obvious Theory Of Everything

    I. EOTOE, Some Implications (I)

    A.
    EOTOE is an Embarrassingly Obvious Theory Of Everything.

    In essence it states that all things in the universe, nouns and verbs objects and processes, originate and derive from the energy-mass dualism.

    Origin and essence of this derivation are expressed mathematically by

    E=Total[m(1+ D)] (D = distance travelled by mass since singularity)

    Which suggests that the universe cycles between two poles: singularity/all-mass , and maximum-expanded/nearly-all-energy.
    The “nearly” all-energy leaves behind some mass formats that begin consolidating by gravity, when it eventually overcomes expansion as the mass fueling the expansion is nearly depleted, becoming very small m multiplied by very large D = E .

    B.
    Thus the essence/definition of gravitation is:
    “Gravitation Is the propensity of energy reconversion to mass”.

    Gravitation is the “monotheism” and the “ genesis” of the universe. Singularity, at D = 0, is the very brief all-mass pole of the universe. The Big-Bang-inflation did not produce matter or anti-matter. It was the beginning of mass reconversion into energy, of increasing D fueled by decreasing m.

    The conjectured gravitons, smallest basic particles, most probably do exist, but must be with mass, and gravitons microclusters must “big-bang” during the on-going expansion at a resolution of their energy-mass superposition.

    This is rationally commonsensical, therefore it is scientifically probable.
    Inflation started with the whole universe m shattering into fragments that evolved into, became, the galaxy clusters. The clusters expansion is fed at a constant rate by m-fuel. Since expansion accelerates, since the clusters depart from each other at an ever increasing velocity, we learn that the rate of m-to-E reconversion in the universe is constant. The accelerated expansion derives from the ever decreasing m of each cluster.

    C.
    Thus the essence/definition of evolution, natural selection is:
    Mass formats attaining temporary augmented energy constraint in their successive generations, with energy drained from other mass formats, to temporarily postpone, survive, the reversion of their own constitutional mass to the pool of cosmic energy fueling the galactic clusters expansion.

    This explains why black holes and humans, in fact all mass formats, must feed themselves in order to survive.
    This explains that the essence of quantum mechanics of all processes is the detailed procession steps, the evolution details, between physical states ordained for natural selection.

    D.
    Thus comes to light the universe inspected progressively in greater detail.
    Science reveals the universe’s nature-scope and directing drive, followed by technology studying its evolution details-aspects, followed by engineering exploitation of the attained information. This suggests the specific weight, importance, of science, technology and engineering in considering of research or enterprise plans and implementation.

    Dov Henis (comments from 22nd century)
    http://universe-life.com/

    PS1:
    Definitely: Dark energy and dark matter YOK! Universe's m reconverts to E at a constant rate…
    Universe accelerated expansion is per Newton's motion laws, obviously…
    Also, universe physics constants should vary, probably slightly, between galaxies clusters due to different clusters sizes...
    Also, the clusters formed by dispersion at inflation…

    PS2:
    The singularity constituents must have been the smallest elementary particles. They may be designated gravitons, but they MUST HAVE MASS. They were born at the energy-mass superposition resolution, together with the fragments that became galaxies clusters.
    At expansion D increases, therefore m decreases, which per Newton mandates mass and matter acceleration. This goes on, most probably, at a constant rate of mass-to-energy reconversion, at an energy-mass resolution, mandated by the equality of both sides of the top equation.. And this resolution is, for each graviton, most probably in a format of a minuscule big-bang.

    This is a lesser fantasy than the dark matter and energy fantasy. Such mass-energy gravitons may be omnipresent within each galaxies cluster, maintaining each cluster as a primordial Newtonian body and being the fuel-driver of expansion.


    II. EOTOE, Some Implications (II)

    This equation describes the presently expanding universe:

    E=Total[m(1 + D)] D = distance travelled by mass since singularity

    This equation describes the future contracting universe:

    E=Total[m(1 + D)] D = reduced expansion distance travelled by mass in the preceding expansion phase

    Implications:

    The base units of mass - may be designated gravitons but MUST have mass - are not temporal, they never disappear.

    In the present expanding universe they are in motion as mD away from the singularity point.
    Those of them that hit a whatever mass format and move it become inert. This will go on until all or nearly all of them cease moving forward, i.e. until D ceases growing.

    When D ceases growing gravitation will overcome the inertial motion away from the singularity point and will start pulling them back towards it. It is then that D will start diminishing, to maintain the equation’s equality…

    And MORE, MUCH MORE:

    The rational commonsensical, and therefore scientifically probable, implication is that Space is imbued with these massed gravitons that are continuously left behind during Expansion… also as micro clusters sized between gravitons and neutrinos…


    III. EOTOE, Some Implications (III)

    Classically:

    Energy = dynamic quality, the capacity of acting or being active, a fundamental entity of nature that is transferred between componentsts of a system in the production of physical change within the system and usually regarded as the capacity for doing work.

    Mass = Mass is the quantity of inertia possessed by an object or the proportion between force and acceleration referred to in Newton’s Second Law of Motion.

    Per EOTOE :

    E=Total[m(1 + D)] D = distance travelled by mass since singularity

    Energy is mass in motion.

    The mass of the universe is either in motion or in the form of inert massed gravitons, with which the universe is imbued.

    m of the EOTOE equation is only the energetic m, the m which is in motion.

    The inert gravitons do not play a role in the E,m,D relationship. At the (present) universe expansion phase mass reconverts to energy at a constant rate, leaving behind inert gravitons. Inert gravitons become energetically active when they are reset in motion, i.e. when acted upon by energy, such as by gravity during the universe re-contraction phase.

    Dov Henis (comments from the 22nd century)
    http://universe-life.com
    On Light And Dark Mass And Energy
    http://universe-life.com/2011/10/03/on-light-and-dark-mass-and-energy/


    IV. EOTOE, Some Implications (IV)

    This equation describes the future contracting universe:

    E=Total[m(1 + D)]
    D = reduced expansion distance travelled by mass in the preceding expansion phase

    Elaboration and conjectured implications:

    D is the distance travelled by mass in all spatial directions emanating from the Big-Bang singularity point. During contraction it decreases, accompanied with increasing m effected by the constant E.

    A commonsensible conjecture is that contraction is initiated following the Big-Bang event, steadily re-forming the Universe Singularity simultaneously with the inflation and expansion, i.e. that universal expansion and contraction are going on simultaneously.

    Additional conjectured implications are that the Universe is a product of A Universal Black Hole with a Singularity consisting of mass gravitons, and that gravitation is a weak force due to the graviton’s size.

    Dov Henis (comments from the 22nd century)
    http://universe-life.com/2011/10/07/eotoe-some-implications-i/
    http://universe-life.com/2011/10/14/eotoe-some-implications-2/
    http://universe-life.com/2011/10/26/eotoe-some-implications-iii/

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  14. 14. Dov Henis 04:10 AM 1/2/12

    On The Universe and Life Comprehensions, EOTOE (V) and (VI)

    EOTOE, Some Implications (v)

    The Gravitons Nature-Origin Puzzle

    My model for the EOTOE has been evolutionary biology. Since life must be just another mass format, and due to the oneness of the universe, it is commonsensical that natural selection is ubiquitous and that life, self-replication, is its extension. And it is commonsensical, too, that evolutions, broken symmetry scenarios, are ubiquitous in all processes in all disciplines and that these evolutions are the “quantum mechanics” of the processes.

    However, there is yet an origin of origins puzzle.

    Whereas the genesis of genes, life’s primal organisms, is rationally commonsensical, thus highly probably, the “naturally-selected” RNA nucleotides - the existence, origin and nature of the rationally commonsensical conjectured massed graviton are yet much farther from probable than the nucleotides life’s genesis. The gravitons are more enigmatic because science has not yet accumulated the extent and variegated considerations and examinations required to approach the comprehension of the origin of origins of the universe.

    PS: From
    http://universe-life.com/2011/12/13/21st-century-science-whence-and-whither/
    notwithstanding…
    “The origin-reason and the purpose-fate of life are mechanistic, ethically and practically valueless. Life is the cheapest commodity on Earth. Human life is just one of many nature’s routes for the natural survival of RNAs, the base primal Earth organisms.
    It is up to humans themselves to elect the purpose and format of their life as individuals and as group-members.”
    ===========================

    EOTOE, Some Implications (VI)

    Yet something about the gravitons

    Yet one possible conjecture about the gravitons is that they, too, must have a dual mass-energy nature…

    From singularity it is a rationally commonsensical conjecture that they are a mass format, the smallest elementary mass particles.
    Nevertheless from the Big-Bang it is a rationally commonsensical conjecture that they must also be energy, i.e. mass in motion, even at singularity. This is rationally commonsensical since otherwise the Big would not Bang…

    This raises the origin of origins puzzle to an unknown power…

    Dov Henis (comments from 22nd century)
    http://universe-life.com/2011/12/10/eotoe-embarrassingly-obvious-theory-of-everything/

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  15. 15. Dov Henis 05:31 AM 6/12/12

    1. Dark energy/matter YOK...
    2. Galaxies clusters separation accelerates per Newton as clusters masses decrease at constant rate..

    Natural Selection Is Ubiquitous

    Higgs Particle? Dark Energy/Matter? Epigenetics?
    These Are YOK!
    Update Concepts-Comprehension…
    http://universe-life.com/2011/12/13/21st-century-science-whence-and-whither/

    Evolution Is The Quantum Mechanics Of Natural Selection.
    The quantum mechanics of every process is its evolution.
    Quantum mechanics are mechanisms, possible or probable or actual mechanisms of natural selection.
    =================

    Universe-Energy-Mass-Life Compilation
    http://universe-life.com/2012/02/03/universe-energy-mass-life-compilation/

    A. The Universe

    From the Big-Bang it is a rationally commonsensical conjecture that the gravitons, the smallest base primal particles of the universe, must be both mass and energy, i.e. inert mass yet in motion even at the briefest fraction of a second of the pre Big Bang singularity. This is rationally commonsensical since otherwise the Big would not have Banged, the superposition of mass and energy would not have been resolved.

    The universe originates, derives and evolves from this energy-mass dualism which is possible and probable due to the small size of the gravitons.

    Since gravitation Is the propensity of energy reconversion to mass and energy is mass in motion, gravity is the force exerted between mass formats.

    All the matter of the universe is a progeny of the gravitons evolutions, of the natural selection of mass, of some of the mass formats attaining temporary augmented energy constraint in their successive generations, with energy drained from other mass formats, to temporarily postpone, survive, the reversion of their own constitutional mass to the pool of cosmic energy fueling the galactic clusters expansion set in motion by the Big Bang.

    B. Earth Life

    Earth Life is just another mass format. A self-replicating mass format. Self-replication is its mode of evolution, natural selection. Its smallest base primal units are the RNAs genes.

    The genesis of RNAs genes, life’s primal organisms, is rationally commonsensical thus highly probable, the “naturally-selected” RNA nucleotides.

    Life began/evolved on Earth with the natural selection of inanimate RNA, then of some RNA nucleotides, then arriving at the ultimate mode of natural selection, self-replication.

    C. Know Thyself. Life Is Simpler Than We Are Told, Including Origin-Nature Of Brain-Consciousness-“Spirituality”***

    The origin-reason and the purpose-fate of life are mechanistic, ethically and practically valueless. Life is the cheapest commodity on Earth.

    As Life is just another mass format, due to the oneness of the universe it is commonsensical that natural selection is ubiquitous for ALL mass formats and that life, self-replication, is its extension. And it is commonsensical, too, that evolutions, broken symmetry scenarios, are ubiquitous in all processes in all disciplines and that these evolutions are the “quantum mechanics” of the processes.

    Human life is just one of many nature’s routes for the natural survival of RNAs, the base primal Earth organisms.

    Life’s evolution, self-replication:

    Genes (organisms) to genomes (organisms) to mono-cellular to multicellular organisms:

    Individual mono-cells to cooperative mono-cells communities, “cultures”.

    Mono-cells cultures evolve their communication, neural systems, then further evolving nerved multicellular organisms.

    Human life is just one of many nature’s routes for the natural survival of RNAs, the base Earth organism.

    It is up to humans themselves to elect the purpose and format of their life as individuals and as group-members.

    Dov Henis (comments from 22nd century)

    ***המקור והמהות של "רוחניויות", כולן וירטואליות,
    הרוחניויות נובעות מהמאמינים, לסיפוק ולשימוש שלהם

    An Embarrassingly Obvious Theory Of Everything
    http://universe-life.com/2011/12/10/eotoe-embarrassingly-obvious-theory-of-everything/

    Tags: brain origin, gravitation, gravitons, lifeevolution, nerved organisms, RNAlifehood, spirituality, universeevolution

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