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Raise the screen over a galaxy composed of dark matter

A cluster of young stars - pulsars discovered on the far side of the Milky Way Galaxy may mark the location of a dwarf galaxy that is mostly composed of dark matter and, in addition, is hiding behind clouds of dust.

The Milky Way. Illustration: shutterstock
The Milky Way. Illustration: shutterstock

A team of researchers led by Suknia Chakrabty from the Rochester Institute of Technology analyzed data in the near-infrared field taken by the VISTA sky survey conducted by the European Southern Observatory telescopes and discovered four young stars at a distance of about 300 thousand light years. The young stars are of the Cepheid variable type, which serve as the "standard candles" that astronomers use to measure distances in space.

According to Chakrabati, these are the most distant Cepheid variables that can be found near the plane of the Milky Way. These stars appear to belong to a galaxy that Chakrabty predicted existed in 2009 after analyzing ripples in the Milky Way's outer disk. The previous study predicted the location of that dwarf galaxy composed mostly of dark matter. The radiation emitted by the cephalic variables allows her to derive exact distances and check the forecast.

Chakrabty analyzed the VISTA database containing data on tens of millions of stars. During the review, she discovered these cephalic variables in the Norma group, about one degree apart.

"These young stars are the hallmark of the predicted galaxy," says Chakrabty, an assistant professor in the Rochester Institute of Technology's School of Physics and Astronomy. "They cannot be part of our galaxy because the disk of the Milky Way ends at a distance of 48 thousand light years.

Invisible particles, known collectively as "dark matter" make up about 23% of the mass of the universe. The mysterious matter is a fundamental problem for astronomy because its nature is still not understood," says Chakrabati.

"The discovery of the Cepheid variables showed us that the method of discovering the location of dwarf galaxies consisting mainly of dark matter works" she said. "It may eventually help us understand what dark matter is made of. He also shows that Newton's theory of gravity can also be used at the edge of the galaxy, and there is no need to correct the theory of gravity.

Vista's infrared eyes allow scientists to explore unfamiliar regions close to the galactic plane that are inaccessible to optical surveys. The visible wavelength cannot penetrate the dust and gas in these areas. This kind of advanced sky survey can help scientists observe galaxy structure and distant stars at low latitudes. Infrared surveys can help resolve the contradictions between observations and paradigms by providing a more complete view of the Milky Way's structure, Chakrabati says.

"I decided to see if I could actually find it," said Chakrabty. "This was a difficult prediction to test because the galaxy is close to the plane of the Milky Way and therefore difficult to observe in the optical field. The new survey, Vasita was able to help us lift the curtain and see the young pulsars".

The article was published in the Astrophysical Journal
to the notice of the researchers

73 תגובות

  1. skeptical
    And again you write me a comment...

    By the way, I don't accept the "Torah from Sinai" - maybe that's why you treat things in such a stupid way?

  2. skeptical,
    Yesterday I talked with my dear partner about why there are so many people who call themselves a nickname that has the root SPK on the science website and how it happens that these are the least skeptical people. I don't think you understand what it means to doubt. You question anything that goes against your agenda. great. But this is not skepticism. Skepticism is questioning even the things that serve your agenda and that's not what anyone with that root bothers to do here.
    Another thing in skepticism that the SPK people don't like to do is the ability to get to know the subject in depth before passing the criticism and "casting the doubt".
    Me, personally, and from my impression also all the other commenters who "go like a herd after the scientific theories they receive as Torah from Sinai" don't really do that. What we do is understand when the limit of our understanding is over and when we are unable to criticize a certain subject simply because we do not have the tools. In such a case, experience teaches me that it is indeed better to listen to someone who clearly understands the subject (in this case Albanzo) than to someone who clearly "doubts" and passes criticism just for the sake of passing the criticism when he has no idea about the subject (in this case the SPK people). If it is called following the herd and accepting scientific teachings which are probably very well established as the Sinaitic teachings, I am proud to be part of the herd. In my research areas, by the way, I am very inclined to doubt, but, you know, properly, while understanding the subject. Maybe you should try it sometime.

  3. miracles,

    This is at least the third time I am writing to you because you do not deserve a response...

    I feel sorry for all those who write here
    who practice the custom of a herd,
    and accept without question all "scientific" theories as Sinaitic Torah...

  4. Skeptic (...alek),

    Really, it's a shame and disgrace that the science site gives titles that you don't like and that don't match what you *decided* (without any examination of the theoretical or experimental background) to be true. Hurry, write a complaint to Abi Blizovsky.

    And for that matter - the dark matter is indeed found. It is found in large clusters, but not in individual particles. What has not yet been found and is still missing to complete the model, is a single particle of dark matter - which we can look at and say what its microscopic properties are (mass per particle, charge under the various forces, etc.). Clusters of dark matter have been observed throughout the universe for many years. If my memory serves me correctly, the first confirmed observation of dark matter was in the Bullet cluster. But between us - what's the point of trying to explain to you...? After all, walking death already gave you a reference that shows that they measured the propagation speed of gravity and found to an accuracy of 1% that it moves at the speed of light. Did it bother you to completely ignore it and continue to claim that no one ever thought to check it?

    "skeptical". Yeah right. Just one more in a long line of commenters on the science website who want to challenge the scientific consensus from outside interests (whether religious like the repentant commenters who sometimes appear here, whether out of feelings of inferiority and the need to show that "all these scientists are not smarter than me!", etc.) , and decided that they could do this without bothering to learn even the most basic things about the theories they were challenging (at the theoretical or experimental level - that is, what evidence and evidence there is for the correctness of the theory they don't like).


    The fact that gravity is a curvature of space does not mean that it is instantaneous. Also in the theory of relativity, gravity moves at the speed of light. That is, if there is any distribution of energy in space, then it will have a certain form that we will perceive as gravity. If you change the distribution of energy - for example, you move a particle with some mass from point A to point B - then the geometry of the space will change accordingly, but in a continuous and gradual manner, which can be described exactly as the movement of a wave moving at the speed of light.

  5. incidentally,

    I would expect from the respected science site,
    Not to write the misleading title at the top of this article...

    The title implies that the dark matter is indeed found...

  6. Gravity does not depend on the speed of light at all.
    We also exert gravity on objects beyond the visible range of the galaxy, because it is a curvature of space-time.

  7. skeptical

    "A solar eclipse causes there to be a tiny deviation in the power of the sun
    Attracts the Earth..."

    what? In what world? By what mechanism?

    Like, on the one hand I'm really glad it's not the stupid thing I thought you were thinking on the other hand this thing isn't really better in any way.

    Have you considered trying to understand the thing you are talking about a little before you start criticizing and talking about it?

  8. Your answer to walking death in Italian is defined as mumbo jumbo. And in spoken Hebrew, Harta Barta.

  9. walking dead

    Her mistake!
    A solar eclipse causes there to be a tiny deviation in the power of the sun
    pulls the globe.
    Because of the addition of the moon's gravity.

    It may be better to do the tests during an olfactory impairment
    Then the attraction will be in reducing the attraction of the moon.

    All you need to check
    Length of response time to change.
    This added or subtracted gravity.

  10. The most reliable is Eddie.

    The most relic - Yossi.

    And the most faithful - Yuval.

  11. skeptical
    I didn't understand me, I'm sorry. I don't respond for you to respond back, I'm not interested in hearing your bullshit. I am responding so that readers a little smarter than you can see what a fool you are.

    I'm sorry I wasn't clear.

  12. Wait, I think I got it.

    A skeptic thinks he forgot the attraction carried by light (probably because of the speed of light), and that during a solar eclipse, because the light does not reach part of the Earth, it affects the gravitational force between the Sun and the Earth.

  13. Israel
    There is the "Amos" satellite, but you cannot see it without digging a deep hole - it is at longitude 5...

  14. skeptical
    You don't really understand how science works, nor do you understand physics very well.

    Look at science like any art and sport. The three things have no purpose, and all three "waste" money.

    And regarding a solar eclipse - where do you conclude that the sun's gravity changes??

    There is no known case where information passed at a speed higher than c. There is no reason to think otherwise.

  15. To the anonymous user,

    Many millions of dollars of public money
    referred to the parties who "investigate" the wrong theories or rely on them,

    Like the "big bang" theory and at least part of the "speed limit" theory.

    They have no interest in bringing an end to ambiguity on these issues.

  16. skeptical

    Who has an interest in answering the question? Why?

    And speaking of conspiracies: what about the few socks in the laundry?

  17. Israel.

    Obviously such a fundamental question
    Can't solve on the blog

    Intaxant factors, of the kind that receive appropriate public budgets,
    Want this topic to remain obscure.

    It seems to me that sensitivity tests during a solar eclipse can give an answer.

    You have to take into account that it is stuck in a time of 16 minutes (going back to the sun)
    Which should give a clear answer..

  18. skeptical

    Regarding what you asked:

    "An answer to this question will put an end to the controversy about whether information can move
    At a speed exceeding the speed of light..."

    I have posed this question on several blogs. Here is the wording:

    "Although it is not possible to transfer information through entanglement, and Bell's theorem and the Aspect experiment proved that there are no hidden variables, doesn't this require that information - the state of spin or polarization - passes from one entangled object to another?"

    The only answer I received so far was from Guy Hatzroni:

    "This is a bit of a big question for the forum (I will gladly discuss it here face to face), and it does not have an agreed upon answer."

    It is not clear to me how information can not pass between entangled particles, but so far I have not received an explanation other than "non-local correlations".

  19. I would suggest conducting simple experiments
    during a solar eclipse.

    in such an event,
    The Sun's gravitational pull is significantly smaller,
    And you can simply measure, if it is immediate or takes 8 minutes until the effect begins and expires..

  20. About Einstein..

    Why do we need another reference? marriage certificate?

  21. Emphasize,

    Answering this question will put an end to the controversy about whether information can move
    At a speed that exceeds the speed of light...

    It seems to me that the answer to this question,
    should be the first priority of the entire scientific front
    And it is appropriate to give her clarification all the necessary resources...

    It will bring an end to wasting money on subjects that are no longer worthy of research...

  22. Food for thought,

    If a double star system exists,
    That is: a pair of stars that revolves around a common center of gravity,
    and one of the stars is suddenly diverted from its orbit (external force),

    Will the reaction in the position of the opposite star be immediate
    Or only after the time has passed for the information to reach him, at maximum speed, which is the speed of light?

    Assuming that there is no answer, it was expected of "science" to make observations b

  23. Miracles

    Come visit..

    Do you know perhaps from which geosynchronous satellite a clear and stable signal can be received and which scanner is available? The natural choice is SIRIUS XM, but they have a 4.5 second BUILT IN delay that messes up the stability of the signal.

    By the way, do you get video ads in the comments or is it just me?

  24. Israel
    I will think about the formula tomorrow 🙂
    By the way, was in your area last week - UCSF. And I hope to get to UCLA soon.

  25. Jenz
    It is very possible that the universe is infinite. We are able to see up to a certain limit because light, and any other way of transmitting information, is limited to the value c. This does not mean that there is something blocking, it means that information cannot be received beyond this distance.

    I don't understand where the problem is.

  26. Miracles
    I admit I admit I didn't understand you.
    Do you mean that I don't know the word "observed"?
    Even if the observed universe is of size x this indicates that the limit of the universe is x. Simply because there is nothing beyond that no matter how much you try to expect or calculate.

  27. Miracles
    13.7, 46 These are "final numbers".
    Infinity is defined in a different way.
    If the universe is 96 mils in size then it is finite, even if tomorrow it will be 97 it will still be the limit - 97.

    In my unprofessional opinion, the envelope exists.
    The envelope is the dark energy and it functions like a black hole that sucks all the matter and energy into it and transfers it to an outer envelope which by its very definition defies all logic and existing laws of physics.

  28. Jenz

    So where is the envelope? And why exactly there? What about homogeneity, isotropic, anaraf..

    The cart is Michael's blog. He now writes about the Holocaust, and claims that anti-Semitism is not because of the Germans. I told him that it was true, it was because of the Jews.

  29. Miracles
    If the universe has a limit - even if the size of the limit increases - then the universe is finite.
    What is the definition of "universe"? – All matter contained within space-time? Dehino - a shell of matter and energy.

    After the universe there is a shell that makes no sense to us 🙂

    The question is not: what is the shell?
    The question is: does the shell exist or not?
    And if so, then it solves a lot of problems related to the second law of enderlamusia.
    And tell this Michael to get on the cart, otherwise it doesn't work like that..
    And Yuval... well...

  30. I don't think I understood the question.

    Don't know if the universe is finite or not, or how it's related.

    In any case, the size of the observed universe is not equal to the size of the universe (under our current understanding of the matter).

  31. Miracles

    You said "the radius of the observable universe is about 46 billion light years", Za Sofi.

    And what limits an infinite universe?

  32. Miracles

    How does a finite radius for the universe compare with an infinite universe?

    Jenz and the striped shirt

    A shell for the universe? And what's next, sea?

    I spoke yesterday with Yuval (or what's left of him). Michael can be reached by cart, but you have to run fast.

  33. Jenz
    Nothing mandates, or even implies that there is a shell for the universe. And - I know of no evidence that the universe is finite.
    I would love to learn from you..

  34. Israel
    Zvi says the universe is infinite. But there is also evidence to the contrary. It does not matter. None of the claims have been proven yet.
    What is interesting is that, according to logic, a shell is required for all material. We call it a universe. But, even the universe according to logic should be contained within something - no matter how illogical it may be... But interesting... isn't it?
    After all, everything is inside something.
    As you increase the resolution, you reach such a conclusion..
    Interesting, isn't it?

  35. The radius of the observable universe is about 46 billion light years, not 13.8 billion.
    And there is no contradiction here...

  36. Wookie what's up?

    It seems to me that everyone is wintering now in Israel, only with us it is spring, the daffodils are blooming and the crocus..

    Zvi says that the universe is probably infinite. So how does this stack up to the diameter of the universe?

    And what will the Honorable Rabbi Yakom say about it? Where are all the universes contained and in which universe?

    Who knows - rehabilitation!

  37. skeptical

    The professor is right.

    And what's the problem with 13.7 billion years? Calculate the expansion rate of the universe by measuring the distances of the galaxies from each other, reverse the direction and calculate when they were together. That's the number you'll get, isn't it?

    Your second question is about the size or diameter of the universe, and the number you gave is quite close to the approximate size (not that I understand what "size of the universe" means because what's after that, Kir?).

    But here's something nice to have fun with:

    If G is Newton's gravitational constant.

    M is the mass of the universe.

    R the radius of the universe.

    c the speed of light

    So roughly: GM = Rc^2.

    Nice, huh?

  38. I once asked a professor of astronomy at Tel Aviv University
    "In which direction did the "Big Bang" occur?
    He was embarrassed by the question and answered "It is impossible to point to the direction".

    I was shocked…

    I would be happy if I get an answer here to my questions about the connection
    The sacred number 13.7 billion years of the existence of the universe.

    If you look at distant galaxies in the east direction, you will see a maximum
    At this distance of light years.
    If we look towards the west, we will again be seen at this distance of light years.

    Doesn't this mean that the space of the universe should be 13.7 times 2 light years?
    (ie 27.4 billion)

  39. Albanzo, what's up?

    Listen, I have a hard time reading English, especially when it contains terms I don't know. And I'm not well versed in the field of advanced physics.
    Could you take one of the pieces of evidence from the article you brought, and simplify it for our benefit, as far as possible for you?

  40. Eddie,

    Yes. I know a lot of people who know dark matter theory very well. They don't talk about her until they know what her strengths are, and what her weaknesses are. What can be tested in an experiment, and what can't.

    We know a lot about dark matter. But, we don't know everything. Mainly we do not know the microscopic properties of the particles that make it up - properties such as mass per particle, charge under the weak force (just as there is an electric charge under the electromagnetic force, there is also a charge under the weak force), etc.

    So a scholastic like you will come and say that we actually don't know what dark matter is. So you have to ask yourself, if 30-40 years ago you would have said that we don't know what an electron is. Yes, a few decades ago still not much of the microscopic properties of electrons. Not to mention protons, neutrons and other baryons, which we didn't even know what they were made of (reminds you of something....?). So if we were corresponding in 1970, would you try to convince me that electrons are a "spaghetti monster" and all the nonsense you said earlier?

    Do I know positive evidence for the existence of dark matter? Honestly, it's a bit hard for me to answer that. Not because I don't know, I'm just too busy laughing. Just kidding because in the previous comment I attached a link to a scientific article whose title is "evidence for the existence of dark matter". So you didn't even bother to read what I wrote. Well, well, not really surprising coming from a man who feels comfortable writing about theories that are wrong when he knows nothing and a half about them.

    "But", the wise man will say, "all the evidence we have is indirect! The theory of dark matter produces a predication, and the predication is adjusted when it is tested in the laboratory, but we do not hold dark matter in our hands, and we do not know what its particle composition is, so we have to ignore the mountains of evidence for its existence!" Well, right. Sorry for bothering.

    Only... once again our friend the electron came to our aid. Do you think he is just a physicists dream? I ask because no one has ever seen an electron. didn't hold it in his hand. All the evidence we have for the existence of electrons is indirect. There is a theory of the existence of electrons, it has predictions, and we test them in the laboratory. But no one has ever seen the particle, because it's just too small.

    So if you want to return to a parametric form of research (literally, you can't even call it science) that advocates "if I haven't seen it with my own eyes, then it's not true", you're welcome. Say hello to the 16th century, please. We have progressed to an era where objects can be photographed millions of light years away, where any two points in the world can be communicated with in 0 time, when life spans can be tripled and the secrets of the universe cracked - not by deciding to ignore indirect evidence because it is not real enough for some commenter on the Internet ….

    And by the way, don't think I didn't notice that you ignored it. You ignored that you *do* know nothing about dark matter theory. that you don't know and didn't bother to check if it has evidence (come on, a Google search would already show you that it has mountains of positive evidence), that you have no idea what the phrase "spaghetti monster" means, that your comparison to religion is detached from reality and just demagoguery, and that you don't understand at all Ockham's razor (or at least, that you are not willing to reveal to us the other possible solutions that do not fall in their predictive power from the dark matter solution). You talked nonsense, you were exposed as a nonsense speaker, and when you didn't have anything to say - then you simply ignored it and moved on, hoping that the fact that the post you wrote barely contained 2 words that were not ignorant bordering on stupidity would be largely forgotten. But again - what can you expect from a man who is not afraid to slander on the Internet a theory he knows nothing about? integrity? A minimum degree of ability to think and analyze scientifically? Understanding of the need to reason and explain his claims? No way. All that is needed is to continue grinding more demagogic and senseless arguments to convince that if Eddie does not understand what the theory of matter is, why it is in the scientific consensus, and why it works - then no one understands!

  41. Miracles That's why I said "to see" and the intention is through our senses and even if it is with the help of elaborate measuring devices. Therefore it is possible to "see" air. Forces are something else, but they are always related to matter. Here there is *matter* that cannot be "seen" but only the force of gravity that is affected by it.

  42. Raphael
    There are many things in the world that cannot be seen, but only their effect.

    Gravity for example. Magnetic field for example. Air for example...

    Don't be fooled by the nonsense of the commenters here who dismiss dark matter without understanding what they are talking about. I don't understand physics at a high level, and I avoid making a judgment on a subject I don't understand enough.

  43. dear elbentzo,
    First of all, you're right... I don't know what 'dark matter' is.
    By the way, do you know someone who does?
    I really appreciate the knowledge of people of your kind. But - do you know what dark matter is? Do you have a plausible concept for it?
    Do you know of positive evidence (not hypothesis, not speculation, not guesswork) for the existence of dark matter?

  44. From the dark matter we will learn that there are things in the world that cannot be "seen" but we will know about their existence through their effect on things that can be "seen".

  45. Life
    If there is any energy then there is mass. (e=mc^2)
    Therefore dark matter is not empty.
    Apparently its mass is very low.
    But, since the substance cannot be detected by instruments (because it does not respond to electromagnetism in the conventional ways, i.e., in the existing instruments) and therefore cannot be measured either - it is not possible to determine the mass of the dark matter.

  46. Eddie,

    1. You don't seem to know what dark matter is. OK, 95% of the people who comment on dark matter (in general and specifically here on the site) are people who have no idea what the theory says and why. For example, if you knew what dark matter is, you might feel the need to address the fact that it rests on a lot of observational evidence, that it has predictions and that they are verified compared to nature. Your comparison to religion ("idols in the pantheon") is ridiculous because religion is by definition faith-based - that is, without evidence, and dark matter is a theory with a solid evidentiary foundation.

    2. You don't seem to know what the "Flying Spaghetti Monster" is. The Spaghetti Monster was invented as an entity at the base of the Pastafarianism religion. Its purpose is to draw attention to many ridiculous ideas in conventional religions. That is, if dark matter was, as you say, "the spaghetti monster of astrophysics", it means that it was an idea proposed in a ridiculous and not in good faith, which is deliberately ridiculous and shares most of the features of the accepted theories in astrophysics. His purpose was to show that conventional astrophysics is itself ridiculous.

    3. You don't seem to know what Ockham's Razor is. A prerequisite for Ockham's razor (which holds that when solving a problem, the simplest solution - simple in the sense of the one that requires the smallest number of assumptions - is the one that should be chosen), is the existence of several possible solutions. That is, if you encounter a problem of hers *several solutions, none of which gives a better prediction than the others for the solution*, then you have to choose the simple one. Please list the other solutions (apart from the dark matter) that explain the observed natural phenomena in an equally good way and give predictions that hold no less accurately than the dark matter. If you find more such solutions, then apart from publishing them here on the website and silencing me, I recommend that you also publish them in a scientific monthly. A pretty sure recipe for a Nobel.

    For the benefit of section number 1 (in case you did not know that there is evidence for the existence of dark matter) and section number 3 (so that you have an idea of ​​what predications your alternative theory should give and what problems it should solve no less well than dark matter), I am attaching a link to a short document that reviews some of the evidence for the existence of matter Dark. Of course, an intelligent search on Google (and preferably, on arXiv and Inspire) will yield more articles and documents on the evidence and testimonies.

  47. 'Dark matter' is the spaghetti monster of astrophysics. The 'dark energy' is her sister. Together they serve as idols in the pantheon of highly sophisticated but primitive science that suddenly thrives around a few unexplained observations, instead of the god of truth of Ockham's razor.

  48. to the skeptics -
    Dark matter = yellow cheese that does not respond to anything except gravity
    It can be "seen" with the help of -
    -Gravity recycling
    -Effect on the orbits of "non-dark" objects
    - Redshift
    Of course Einstein could be wrong. And there is a "site" or another correction for gravitation is needed.
    Anyone who has studied general relativity and understood what a graceful and simple theory it is, (derived only from basic assumptions of a finite speed of light) - will not be in a hurry to throw relativity in the trash.

  49. incidentally,

    I would love to learn from followers of the "dark matter" theory

    How can we tell if the dark matter or if the "yellow cheese"
    Are they the dominant factor?

  50. the title

    "A cluster of young stars - pulsars discovered on the far side of the Milky Way galaxy may mark the location of a dwarf galaxy that is mostly composed of dark matter and, in addition, is hiding behind clouds of dust."

    I would add "and maybe also consist of yellow cheese"...

  51. Around our galaxy there are many dwarf galaxies that, although they contain few stars, rotate relatively fast as if they contain up to ten thousand times the dark mass (article here on the science website). Just like this galaxy. Of course, it can also be seen in another way that the relationship between the rotation of the galaxy and between Newton Mikri's gravitation formula definitely.
    So instead of raising a curtain over a galaxy composed of dark matter, maybe it's time to lower the curtain over the gravity formula?
    Good night
    Sabdarmish Yehuda

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