Astronomers Reveal Previously Unknown Details About The Milky Way

Previously Unknown Details About The Milky Way

Schematic diagram showing two stages of star formation in the Milky Way galaxy according to Noguchi. In upper illustration, blue (cold) and red (hot) indicate gas. The color map in bottom panel shows distribution of the elemental composition of stars calculated by Noguchi’s model with the purple line indicating how the elemental composition of the gas changes over time (Credit: M. Noguchi, courtesy of Nature). Overlaid contours show the distribution of solar neighborhood stars observed by APOGEE, a spectroscopic device attached to the 2.5 m telescope of the Alfred P. Sloan Foundation at Apache Point Observatory in New Mexico. Credit: M. Haywood et al. A&A, 589, 66 (2016), reproduced with permission © ESO

The Milky Way galaxy has died once before and we are now in what is considered its second life. Calculations by Masafumi Noguchi (Tohoku University) have revealed previously unknown details about the Milky Way. These were published in the July 26 edition of the journal Nature.

Stars formed in two different epochs through different mechanisms. There was a long dormant period in between, when star formation ceased. Our home galaxy has turned out to have a more dramatic history than was originally thought.

Noguchi has calculated the evolution of the Milky Way over a 10 billion year period, including “cold flow accretion”, a new idea proposed by Avishai Dekel (The Hebrew University) and colleagues for how galaxies collect surrounding gas during their formation. Although the two-stage formation was suggested for much more massive galaxies by Yuval Birnboim (The Hebrew University) and colleagues, Noguchi has been able to confirm that the same picture applies to our own Milky Way.

The history of the Milky Way is inscribed in the elemental composition of stars because stars inherit the composition of the gas from which they are formed. Namely, stars memorize the element abundance in gas at the time they are formed.

Previously Unknown Details About The Milky Way Revealed

Model prediction for three different regions of the Milky Way (Credit: M. Noguchi, courtesy of Nature). Contours are from observations by APOGEE (Credit: M. Haywood et al. A&A, 589, 66 (2016), reproduced with permission © ESO).

There are two groups of stars in the solar neighborhood with different compositions. One is rich in α-elements such as oxygen, magnesium, and silicon. The other contains a lot of iron. Recent observations by Misha Haywood (Observatoire de Paris) and colleagues revealed that this phenomenon prevails over a vast region of the Milky Way. The origin of this dichotomy was unclear. Noguchi’s model provides an answer to this long-standing riddle.

Noguchi’s depiction of the Milky Way’s history begins at the point when cold gas streams flowed into the galaxy (cold flow accretion) and stars formed from this gas. During this period the gas quickly began to contain α-elements released by explosions of short-lived type II supernovae. These first-generation stars are therefore rich in α-elements.

When shock waves appeared and heated the gas to high temperatures 7 billion years ago, the gas stopped flowing into the galaxy and stars ceased to form. During this period, retarded explosions of long-lived type Ia supernovae injected iron into the gas and changed the elemental composition of the gas. As the gas cooled by emitting radiation, it began flowing back into the galaxy 5 billion years ago (cooling flow) and made the second generation of stars rich in iron, including our sun.

According to Benjamin Williams (University of Washington) and colleagues, our neighbor galaxy, Andromeda nebula, also formed stars in two separate epochs. Noguchi’s model predicts that massive spiral galaxies like the Milky Way and Andromeda nebula experienced a gap in star formation, whereas smaller galaxies made stars continuously. Noguchi expects that “future observations of nearby galaxies may revolutionize our view about galaxy formation.”

Reference: “The formation of solar neighbourhood stars in two generations separated by 5 billion years” by Masafumi Noguchi, 25 July 2018, Nature.
DOI: 10.1038/s41586-018-0329-2

36 Comments on "Astronomers Reveal Previously Unknown Details About The Milky Way"

  1. Bugsy Muldhoon | August 21, 2018 at 9:35 am | Reply

    And we pay these guys for this? The money could be better spent creating jobs for Americans

  2. This is all planned and precise calculated formation of our galaxy and each layer of protection. Now to understand more The Sun,Air,Water and Fire all are also the creature and have some sort of hearing/listening/obeying capabilities To one and only GOD.
    The knowledge we possess has been given to us and the one we do not know is hidden from us but it does exist. There are seven sky’s?

    • “He” is not “hidden” ! You can find him in your heart. The Creator has attributes and qualities beyond human comprehension. He is no where yet present and “visible” every where. The word “ONE” is not used as the mathematical one (quantity)! The seven skies (to me) refer to seven dimensions .

    • Why don’t both of you get a room and take your religious noises with you? It has no place here.

  3. Curtis, the beach bum | August 21, 2018 at 1:20 pm | Reply

    The guy that did this research is Japanese, the Japanese are the ones who paid for it, It was done at a Japanese research institute, and you think, they would spend their money to create jobs for Americans?
    Furthermore this is the knowledge of the universe, of how it works and how we can fit into it and alter it to suit our needs. This research has profound effects on out lives and is a strong positive influence on our society. We use some of the knowledge that is discovered through science like this to better our lives and to create a better existence for our children. In order for the human race, and actually all life that exists on Earth today to survive we need knowledge like this so that we can reach out beyond our own solar system to new worlds where we can settle and expand our horizons. Without it we will surely die.

    To the sultan and Khurram

    This is science, not religion. The two are separate, one functions by faith alone, and the other requires evidence, observation, careful thought and LOTS of math. You can try to mix the two, but they are diametrically opposed, kind of like oil and water. You really shouldn’t try to mix the two and trying to fit the facts to your religion is not going to work. Let religion stay religion and keep science apart so it won’t be corrupted.

  4. Thank you Curtis!

  5. So this is what we’ve come to re the 3 previous comments: One idiot who thinks Americans pay the salaries of professors/researchers in Japan, and who, aside from having no intellectual curiosity, sees no value in anything except “creating jobs for Americans.” And two would- be cosmogonists still living in the Middle Ages. It is becoming a very scary world.

  6. The power is mythology is fascinating. It is rooted in ignorance and fear and religious people will ascribe anything they personally don’t understand to some deity of their choice. It is pathetic and is a clear example of why dogma and religion has been the cause of so much suffering on earth. God Forbid (yes, that is sarcasm) that these idiots are ever in a position to impact the quest for knowledge about our universe

  7. @Bugsy: Do you realize that nothing creates more and better jobs for people (Americans or otherwise) than scientific research?

  8. @ Curtis You miss the point about combining science and religion. God is the author of both – and one proves the other. They are not diametrically opposed as you suggest, once each is properly understood. As Einstein once said, “I want to know God’s thoughts – the rest are mere details.”

  9. Michael Cleveland | August 21, 2018 at 5:17 pm | Reply

    @Finn: Three vs three. The world of + and – is still in balance and all’s well, and not well, as it will be.

  10. Michael Cleveland | August 21, 2018 at 5:23 pm | Reply

    @Chauffeur I think the missed point is on your side. The difference between Science and religion is that science is observable, testable, knowable, where God is unobservable, untestable, and unknowable. If God is infinite, then thinking you can know God is infinite conceit.

  11. Michael Cleveland | August 21, 2018 at 8:10 pm | Reply

    To add to the above, and maybe the most important point of all: Science begins with an attempt to understand the world through observation, experiment where possible, and rational thought. Religion starts with an immutable idea, which any observations and thought must be molded to fit. The superiority of the one system over the other should be obvious, but it never is to those infected with that immutable idea.

  12. @ Michael Cleveland – From your perspective, it appears your belief for the methodology of evaluating truth is very limited – apparently limited to five senses. Does that mean that truth cannot exist outside of what five senses can observe? Is it possible that a sixth sense might offer greater insight?

    • Michael Cleveland | August 22, 2018 at 4:57 pm | Reply

      And which sixth sense would that be? Define it, show a physiological function, describe how it works. You confuse belief with fact. A thing is true or not true, but belief in it or non-belief does not make it one or the other. If belief were synonymous with truth, then we could all expect to collect our reward of 49 virgins on the other side simply by killing infidels for Allah.

      • Michael Cleveland, suppose half the world were blind from birth. They asked sighted people what “color” or “vision” were but didn’t believe they existed because they couldn’t grasp the explanation provided. Were they correct in insisting that color and vision do not exist?

        I know what I know – and it’s not mere “belief”. It’s a fact, just as certain as you could pick up a rock and call it a rock. As much as I would like all blind people to see, some never will be able to – and it’s not their fault; they’re not culpable. But for others, that’s not true.

        • Michael Cleveland | August 23, 2018 at 6:13 pm | Reply

          The underlying principles that govern sight and color vision can be explained and understood by a blind person, even if that person cannot experience them directly. There’s the difference.

  13. “The Milky Way galaxy has died once before and we are now in what is considered its second life. ”

    This is pure, unadulterated, weapons-grade bulls#!tonium. As usual, whomever wrote this thinks that what is being said are facts, and writes them as if they are. They are not. They are theories (and some pretty harebrained ones at that). It’s just the mental ruminations of someone who thinks he/she might have an idea what happened.

  14. joel in oakland | August 22, 2018 at 2:04 am | Reply

    @ Chauffeur
    Intuition is helpful in all kinds of activities, including science. But it isn’t science. Intuition depends on Reality Checks to avoid the fog of fantasy. Most people have a very hard time telling the two apart – which is why many sciences use math.

  15. @joel I’m not talking about intuition. It might be convenient for critics to assume that’s the 6trh sense, but that would be incorrect. But in fact, there are ALSO scientific proofs that validate the existence of God. I’m speaking about Eucharistic miracles, incorrupt bodies, inexplicable healings, and validated apparitions etc. – which of course would be just smoke an mirrors to the blind. “There are none so blind as they who will not see.”

    • Michael Cleveland | August 22, 2018 at 5:04 pm | Reply

      There is no science in these things, nor is there any scientific authority that will stand for them. To put these things under the umbrella of science is oxymoronic. Science verifies by observation, measurement, experiment. A scientific observation must be repeatable to gain validity. It must be consequent of definable underlying scientific principles, and miracles, by definition, are unique events, not subject to these kinds of verification. Miracles are by nature and definition precisely anti-science.

      • Michael Cleveland, there IS science in these things. You have to look for it. Some people do not want to find it though. Atheistic scientists have evaluated various miracles (some converting) but all mystified by their findings. Research this one:
        This is merely an introduction. You need to check out the credentials of the stunned scientists and go deeper. Same with all the others. Then, you have to compare that with research from other sources involving similar phenomenon. As your skepticism is eroded, then you need to delve even deeper into the research. But of course, nobody wants to “know” the truth – it’s an inconvenient truth with implications for responsibility. But to the persistent, you can add it all up and realize that our societal reality is an illusion. (But I’m getting ahead of myself.)

      • Michael Cleveland, apparently my reply was deleted because it contained some links. But yes, scientific proof is available, you have to look for it. There are ongoing miracles that can be tested again and again, such as live blood. I had links to the Eucharistic miracle in Tixtla Mexico.

        • Michael Cleveland | August 23, 2018 at 6:40 pm | Reply

          The links are there, but even the stated results are inconclusive and contradictory. It says the event does not have a paranormal origin, yet if you accept it as a miracle, it is by definition paranormal. There are many things to question in this, not the least of which the status of the altogether not-independent church-related “scientist” who led the study. And even if it occurred as stated, it proves only that an event occurred. No cause is proven, no cause is given, nor can be, yet any real proof of what you claim is proven demands a demonstrable connection which you only assume. Sorry, but you’re not there yet. This does not meet the standard of proof. It’s not proof of God because you cannot connect it to God except by faithful assumption. Fundamental principle: The existence of God can neither be proven nor disproven by scientific or logical argument.

          • Michael Cleveland, you have to look deeper. You want a quick reply that provides proof to the biggest issue in the universe. It’s not that easy. I gave one example of hundreds available. You dismiss one, apparently believing that settles the issue. If you were invited to reach into a black box that contained diamonds and other stones, would you quit after the first rock claiming there are no diamonds there? The real issue is (with most atheists) is that they don’t want God to exist, because there are implications to that discovery. “Seek and you will find; knock and the door will be opened to you.”

          • Michael Cleveland | August 24, 2018 at 5:07 pm |

            @Chauffeur: I’ve not said anything settles the issue. I’m trying to get across that it cannot be settled. You don’t have scientific proof of God because you can’t use science or reason to support or refute the existence of God. I don’t care how many examples you offer: it can’t be done. It will always break down when you try to connect an event with an ultimate Cause that is undefinable, addressable only by faith. Science does not address God because God is not within the purview of that way of looking at the world that is science. I’ve never stated anything about my religious beliefs, nor have I ever said I was an atheist. Again, you make assumptions and from those assumptions, inferences that are unsupported by fact.

          • I can’t prove the sky is blue, or that water is wet, but the obvious conclusion is there for a reasonable observer. When you amass overwhelming evidence on any issue, one can argue an opposing view in spite of the evidence. In other words, there’s no “proof” for anything, from a certain point of view. (Obviously, this is unreasonable.)
            btw – I didn’t say you were an atheist.

          • Michael Cleveland | August 26, 2018 at 5:17 pm |

            @Chauffeur The blue of sky is a matter of definition, not proof. It is defined by everything from mutually agreed sensory experience to a specific and measurable range of electromagnetic wavelengths. In the broadest sense, blue is blue. In that context, what you cannot prove is that we all experience the same sensory translation of blue, but the measurable aspect of it defines it and we agree to call it blue. The wetness of water is easily definable in terms of the physics involved, in a continuous series of links between the physical phenomena from contact to the generation and transmission of nerve impulses to the translation of that sensory input by the brain. Overwhelming Evidence (not belief) that can be verified by consistent repeatable observation and measurement leads to Theory, which is the highest level of understanding of a phenomenon or group of phenomena at any given time (not, as too many insist, speculation, and as well, not proof). God is not subject to observation or measurement, so there is no universal truth about God, no proof, only speculation and belief. A thing may or may not be true, but belief alone does not make it so. The remarkable thing about this discussion is that you are the one who is insisting on proof, as though proof were somehow necessary to validate your belief in God. Any rational being necessarily will be agnostic, will acknowledge the fundamental truth that there can be no proof either way, and most theologians will agree with that. Agnosticism has nothing to do with what you believe. Once you recognize that proof is neither possible nor necessary, that faith has it’s own place, you can believe what you want to believe, and believe it as fervently as you will. But there would be less mayhem in the world if believers approached belief rationally, with the understanding that belief is personal, did not assign their beliefs the appellation of Absolute Universal Truth and insist that all other beliefs are inadequate or wrong.

          • Michael Cleveland | August 27, 2018 at 9:42 pm |

            @Chauffeur I’m going to take your so-called proof apart, piece by piece. Let’s start with transubstantiation, in which the wafer becomes the body of Christ and the wine the blood of Christ. Therefore, the whole premise of this particular miracle is skewed, since blood in the wafer (as opposed to the wine) makes no sense, except that blood in the proper red wine would not have been visible, hence not so great a show. Staging is everything. Then there is the added ingredient of cells of heart muscle in the blood. That makes no sense either. Why would they be there? Body of Christ? Then why just heart cells? Those cells either belong to the “miracle” or they were simply present in the blood that was used to fake this. Which is more likely? They are not related to the creation of blood cells, so they really have no place in the miraculously manifested blood, unless they got there by accident along with the blood that was placed in the wafers, which is what you are left with when you shave the whole thing with Occam’s Razor. Getting the blood to appear from the inside of the wafer is technically challenging but not impossible; it’s just a matter of clever packaging. And let’s consider, too, the very long tradition that God doesn’t do demos. There is an element of showmanship in this “miracle” that is very un-God-like if we accord that tradition any validity. Again, when you shave away the improbabilities, you’re left with a clever hoax. I was struck that the conclusions stated that there was no sign of involvement of “the enemy.” On the contrary, if you believe in Satan as an entity, it shows all the signs of perpetration by that enemy, as a perfect method to undermine the value of faith, to replace faith with a false belief in proof. Personally, I am more inclined to put a human face on it, with mundane human actions. If you want to be credible as a true believer, you can’t be gullible. You have to filter everything through a hard screen of skepticism, and realize that there are all too many out there who, for their own reasons, want to take you. Part of that skepticism is recognition of the fact that not all scientists are unbiased, and there are even a few that can be bought. The answer to that it built into the scientific method, which requires that a result be repeatable by independent observers/experimenters, and scientific truth be recognized by a broad collective consensus of peers.

  16. Edward J Chaffee Jr | August 22, 2018 at 7:23 pm | Reply

    Everybody needs to start thinking “Outside the box” and think about the possibility that the universe is just a small adjunct of a far larger universe, like comparing the branch of a tree, our universe, to the trunk it originates from. We are not able to view this “trunk” simply because light has not had the time to cross the void towards us. Has anyone ever noticed fireworks when they ignite, scatter particles away from the main source of the explosion, and that there is an immense, dark night sky between the particles and the center of the explosion?

    • Michael Cleveland | August 22, 2018 at 7:42 pm | Reply

      All well and good, but how is this outside the box? It’s certainly not new. This has all been understood for a long time.

  17. Hey All Above interesting comments from all of you … but I did not mention any religion or religious thoughts.
    God Existence has never been denied and that has nothing to do with religion
    Like you and I am a creature, why not all the planets and galaxies out there could be creature too ?….
    Science is just one pixel on bigger scale of picture…….
    Again I am saying this is very well planned not just happened by itself….
    Just imagine Milky Way is 100,000 Light years in diameter
    How many times we have changed our thoughts about orbit/universe/galaxies and each time some new knowledge pop up and we scrap old theories look at our own limitation of knowledge…

  18. There are layers of growth/developent within any galaxy type. The rings are layers concealing different areas of space; possibly to minimize radiation exposure to a gentile people, probably to hide the celestrial bodies which make up the quarters for other worlds/heavens. A supernova once exploded can create a veil of fine dusts leading to supurb coverage; i.e. a nebula/nebuli.
    Hubble picked up on large amounts of gamma-radiation being emitted from the center of our galaxy, the projected size was huge compared to our own sun (Not sure on the mass, though it is insane!); this large body of mass can generate gravitational pull, thus sending smaller objects into an orbit around.. Our sun is within the orbit of this giant star. We could be slowly entering the next stage of progression as a planetary body of space; our whole solar system is slowly traveling further into our own galaxy! This will help us learn more about our own galaxy by not remaining on the outter edge, learning most of what we know from our sister galaxy: Andronema. Not on topic, though I see this is common… “There is no end to matter, there is no end to space”.

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