Star exploded, survived, and exploded again:

Discussion in 'Astronomy, Exobiology, & Cosmology' started by paddoboy, Nov 9, 2017.

  1. paddoboy Valued Senior Member

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    Star exploded, survived, and exploded again more than 50 years later
    November 8, 2017

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    Artist's impression of a supernova explosion. Credit: European Southern Observatory/M. Kornmesser.
    It's the celestial equivalent of a horror movie villain—a star that wouldn't stay dead.

    An international team of astronomers including Carnegie's Nick Konidaris and Benjamin Shappee discovered a star that exploded multiple times over a period of 50 years. The finding, published by Nature, completely confounds existing knowledge of a star's end of life, and Konidaris' instrument-construction played a crucial role in analyzing the phenomenon.

    In September 2014, the intermediate Palomar Transient Factory team of astronomers detected a new explosion in the sky, iPTF14hls.

    The light given off by the event was analyzed in order to understand the speed and chemical composition of the material ejected in the explosion.

    This analysis indicated that the explosion was what's called a type II-P supernova, and everything about the discovery seemed normal. Until, that is, a few months later when the supernova started getting brighter again.

    Type II-P supernovae usually remain bright for about 100 days. But iPTF14hls remained bright for more than 600! What's more, archival data revealed a 1954 explosion in the exact same location.



    Read more at: https://phys.org/news/2017-11-star-survived-years.html#jCp
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    the paper:
    https://www.nature.com/nature/journal/v551/n7679/full/nature24030.html

    Energetic eruptions leading to a peculiar hydrogen-rich explosion of a massive star:

    Every supernova so far observed has been considered to be the terminal explosion of a star. Moreover, all supernovae with absorption lines in their spectra show those lines decreasing in velocity over time, as the ejecta expand and thin, revealing slower-moving material that was previously hidden. In addition, every supernova that exhibits the absorption lines of hydrogen has one main light-curve peak, or a plateau in luminosity, lasting approximately 100 days before declining1. Here we report observations of iPTF14hls, an event that has spectra identical to a hydrogen-rich core-collapse supernova, but characteristics that differ extensively from those of known supernovae. The light curve has at least five peaks and remains bright for more than 600 days; the absorption lines show little to no decrease in velocity; and the radius of the line-forming region is more than an order of magnitude bigger than the radius of the photosphere derived from the continuum emission. These characteristics are consistent with a shell of several tens of solar masses ejected by the progenitor star at supernova-level energies a few hundred days before a terminal explosion. Another possible eruption was recorded at the same position in 1954. Multiple energetic pre-supernova eruptions are expected to occur in stars of 95 to 130 solar masses, which experience the pulsational pair instability2, 3, 4, 5. That model, however, does not account for the continued presence of hydrogen, or the energetics observed here. Another mechanism for the violent ejection of mass in massive stars may be required.
     
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  3. Kittamaru Now nearly 40 pounds lighter. Staff Member

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    I just saw an article on this posted elsewhere:

    http://www.astronomy.com/news/2017/11/zombie#.WgORj68xcPg.reddit

    I... am very confused by all this. Is it possible it was massive enough (or that it... I dunno, exploded slowly enough?) that it recombined into a star and blew up again? I don't see how... but... yeah. This is weird!
     
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  5. geordief Registered Senior Member

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  7. RajeshTrivedi Valued Senior Member

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    Yes, two violent explosions of this magnitude are not predicted by present mainstream theories, but the same was predicted by me in my paper (Neutron Star as ultimate Mass to Energy Converter) which was accepted for publication by Journal of Modern Physics, but I withdrew due to possibility of further addition to my work.

    What I propose is as follows:
    First let us consider how it is possible for an explosion to give a neat neutron Star. Any explosion as such should damage the entire structure, but mostly supernova explosions leave a neat Neutron Star as remnant. This is also not clear in present mainstream theories.

    This is possible only if Neutron Star structure gets formed inside before the explosion (may be during implosion of the star), this innermost Neutron Star type structure releases energy (as per release of bond energy between quarks as proposed by me), and since NS innermost structure is superconducting type, this huge radiation energy travels away from the center and gets trapped between the upper non (or less) conducting layers causing first violent explosion. This does not damage the innermost Neutron Star structure as the explosion is radially away from it around outer layers. This is what happens mostly.

    But if the original star is massive and implosion is sudden and very dynamic, then it is quite likely that post first explosion, the inner most structure gets inside its schwarzchild radius. In this scenario no Neutron Star structure will be visible even though it is present (inside Event Horizon), this structure in due course continues to release the radiation energy (Quark Quark Compression) which remains inside till the mass reduces so much that the structure comes out of its event horizon, at this point second huge explosion occurs, which could be in the form of jet also.
     
  8. exchemist Valued Senior Member

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    Is a link to your paper available?
     
  9. paddoboy Valued Senior Member

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    Thus seems the most likely explanation Kitt,.....
    https://www.nature.com/articles/nature06333

    Pulsational pair instability as an explanation for the most luminous supernovae:

    Abstract
    The extremely luminous supernova SN 2006gy (ref. 1) challenges the traditional view that the collapse of a stellar core is the only mechanism by which a massive star makes a supernova, because it seems too luminous by more than a factor of ten. Here we report that the brightest supernovae in the modern Universe arise from collisions between shells of matter ejected by massive stars that undergo an interior instability arising from the production of electron–positron pairs2. This ‘pair instability’ leads to explosive burning that is insufficient to unbind the star, but ejects many solar masses of the envelope. After the first explosion, the remaining core contracts and searches for a stable burning state. When the next explosion occurs, several solar masses of material are again ejected, which collide with the earlier ejecta. This collision can radiate 10 to the 50 erg of light, about a factor of ten more than an ordinary supernova. Our model is in good agreement with the observed light curve for SN 2006gy and also shows that some massive stars can produce more than one supernova-like outburst.
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  10. paddoboy Valued Senior Member

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    From your link......
    "It soon became clear this exploding star wasn't conforming to expectations. For one thing, it didn't fade, but shone brightly for 600 days - nearly two years.

    What's more, the astronomers found that its brightness varied by as much as 50% on an irregular timescale, as if it was exploding over and over again.

    And, rather than cooling down as expected, the object maintained a near-constant temperature of about 5,700C.

    60 years later
    Intriguingly, by combing through archived data, scientists discovered an explosion that occurred in 1954 in exactly the same location. This could suggest that the star somehow survived that explosion, only to detonate again in 2014.

    The object may be the first known example of a Pulsational Pair Instability Supernova.

    "According to this theory, it is possible that this was the result of a star so massive and hot that it generated antimatter in its core," said co-author Daniel Kasen, from the University of California, Berkeley.

    "That would cause the star to go violently unstable, and undergo repeated bright eruptions over periods of years."

    That process could even repeat itself over decades before the star's final explosion and collapse to a black hole".

    As Kitt said, weird, weird indeed, but these things happened eons ago and very distant and anomalies are probably bound to reveal themselves on odd occasions. This though is no reason to shout out that the standard cosmology model need be abandoned.


    I'm not sure I understand exactly what you are saying...Let's be frank: Once the Schwarzchild radius is reached, further collapse is compulsory and a BH is formed. There is no reason as yet why this can be shown to be false and I certainly remember arguing that point with you some time ago, and my position was fortified links I gave at that time.
    A Neutron star is pretty dense, (as one might expect ) and is held up from further collapse by NDP. Obviously a Neutron star can also collapse to a BH if enough mass is accreted, so perhaps this type of reaction may explain the multiple S/N explosions. Also in a previous post details are given for another possibility with "Pulsational Pair Instability".
    Again the present cosmological model explains the overwhelmingly vast amount of what we observe and isolated anomalies such as this, is certainly no reason to suddenly over turn what is a highly descriptive and validated model.
    DM did not invalidate GR, and of course with relation to another recent debate I have been having, unexplained UFO sightings do not automatically mean Aliens, if you get my drift.
     
  11. paddoboy Valued Senior Member

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    Perhaps this article today is relevant......a variation perhaps?

    https://phys.org/news/2017-11-hubble-echo-supernova.html

    Hubble spots expanding light echo around supernova
    November 9, 2017

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    Light from Supernova Bouncing Off Giant Dust Cloud
    Light from a supernova explosion in the nearby starburst galaxy M82 is reverberating off a huge dust cloud in interstellar space.

    The supernova, called SN 2014J, occurred at the upper right of M82, and is marked by an "X." The supernova was discovered on Jan. 21, 2014.

    The inset images at top reveal an expanding shell of light from the stellar explosion sweeping through interstellar space, called a "light echo." The images were taken 10 months to nearly two years after the violent event (Nov. 6, 2014, to Oct. 12, 2016). The light is bouncing off a giant dust cloud that extends 300 to 1,600 light-years from the supernova and is being reflected toward Earth.

    SN 2014J is classified as a Type Ia supernova and is the closest such blast in at least four decades. A Type Ia supernova occurs in a binary star system consisting of a burned-out white dwarf and a companion star. The white dwarf explodes after the companion dumps too much material onto it.



    Read more at: https://phys.org/news/2017-11-hubble-echo-supernova.html#jCp
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    the paper:
    http://iopscience.iop.org/article/10.3847/1538-4357/834/1/60

    INTERSTELLAR-MEDIUM MAPPING IN M82 THROUGH LIGHT ECHOES AROUND SUPERNOVA 2014J

    Abstract
    We present multiple-epoch measurements of the size and surface brightness of the light echoes from supernova (SN) 2014J in the nearby starburst galaxy M82. Hubble Space Telescope (HST) ACS/WFC images were taken ~277 and ~416 days after B-band maximum in the filters F475W, F606W, and F775W. Observations with HST WFC3/UVIS images at epochs ~216 and ~365 days are included for a more complete analysis. The images reveal the temporal evolution of at least two major light-echo components. The first one exhibits a filled ring structure with position-angle-dependent intensity. This radially extended, diffuse echo indicates the presence of an inhomogeneous interstellar dust cloud ranging from ~100 to ~500 pc in the foreground of the SN. The second echo component appears as an unresolved luminous quarter-circle arc centered on the SN. The wavelength dependence of scattering measured in different dust components suggests that the dust producing the luminous arc favors smaller grain sizes, while that causing the diffuse light echo may have sizes similar to those of the Milky Way dust. Smaller grains can produce an optical depth consistent with that along the supernova-Earth line of sight measured by previous studies around maximum light. Therefore, it is possible that the dust slab from which the luminous arc arises is also responsible for most of the extinction toward SN 2014J. The optical depths determined from the Milky Way-like dust in the scattering matters are lower than the optical depth produced by the dust slab.


     
  12. RajeshTrivedi Valued Senior Member

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  13. RajeshTrivedi Valued Senior Member

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    Should you not understand what I am saying before throwing it in dustbin.


    Please correct me if any of below points are against your views or incorrect

    1. I fully agree that as per GR once inside Schwarzschild radius, further collapse is imminent.
    2. I think I am correct in saying that as such GR does not talk about state of matter, it talks about geometry of spacetime.
    3. I think I am correct in saying that we do not know any known counter force to balance the gravity beyond NDP.
    4. In absence of known counter force beyond NDP, if the gravitational pressure is more (beyond NS) collapse is imminent.
    5. But collapse to what? we don't know and we call it BH or BH singularity as we cant peep inside Event Horizon.

    Now what I am saying:

    6. As the collapse continues, then a point comes when the gap bewteen quarks reduces.
    7. This reduction in gap between quarks reduces the bond strength as per Asymptotic Freedom (Nobel Winning Theory).
    8. Total mass of a neutron is around 940 MeV, but mass of 3 constituent quarks is only 12 MeV.
    9. So when the bond strength reduces, due to reduction in gap, it is a very natural that at least a part of 940-12 = 928 MeV will be released as radiation.
    10. This release will happen at the most central part of the object. It has to travel away from the centre.
    11. It does that on two accounts, one is the innermost part is fully Neutron and very superconducting type, but more crucial is how the radiation which is produced at or around r = 0, can travel away from centre. Then only the mass would reduce due to exit of radiation.
    12. Simple algebra On schwarzschild radius and spherical packing (kepler conjecture) will establish that for a BH > 3.24 solar mass (which otherwise is a lower mass limit for BH), the innermost 3.24 Solar Mass sphere will be out of its Schwarzschild radius, so there is no restriction on radiation to not travel from r = 0 away, thus reducing the mass, which in due course will bring out the full object out of its Event Horizon and blast.
    13. To clarify #12, for a 1 million solar mass BH, the Schwzrschild radius is around 3 million Kms, and Schwzrschild radius for 3.24solar Mass is around 10 Kms. So when an object of 1 million solar mass is just at its Schwzrschild radius, the 3.24 solar innermost mass will occupy >>>>>10 Kms. So a photon produced at r = 0 will have no problem in travelling in inner areas.

    To sum it up, the continued collapse would release the radiation energy, this will reduce the mass of the object from inside and a stage comes when the object comes out of its event horizon, thus exploding to the universe. No BH singularity.
     
  14. NotEinstein Registered Senior Member

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    Quick question: Let's assume you are entirely correct. What kind of object would remain? If a neutron star radiates away the bonding energy between quarks, surely it will collapse a bit further, causing more bonding energy to be radiated away. Now, if it never reaches the Schwarzschild radius this way, what are the properties of the object that's left behind after it reaches an equilibrium (energy radiating away vs incoming radiation)? Does it still have neutrons, but now super-squeezed? Or are they no longer neutrons?
     
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  15. paddoboy Valued Senior Member

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    Its not a matter of 'my views" or your views either, it's the data and research undertaken by the professional experts with access to a myriad of scientific instruments, and the results that they determine.
    Compulsory is a better word.
    Yes.
    Yes
    Yes
    Since the collapse as per GR is compulsory, I would suggest it continues, at least up to where GR fails us at the quantum/Planck level. The mathematical singularity of infinite quantities most likely does not exist and most reputable cosmologists now accept this.
    OK, I believe I get the point you are making. This supposed gap between Quarks is pretty difficult to fathom from where you are in the macro world...then of course we have the gluons. Taking into account GR fails us at the quantum/Planck level, my reasoning is opposite to yours. I see any compression beyond NDP as being affected by tidal gravity effects, and subsequently as particles approach the region we call the quantum/Planck level, the quarks are actually ripped asunder. These are my own thoughts just as your thoughts are your own.
    Here are a couple of links I did find......
    https://www.physicsforums.com/threads/void-between-plank-particle-and-quark-what-else.871837/
    https://www.quora.com/Since-there-i...an-that-the-space-between-is-at-absolute-zero

    And finally I'm rather interested in how you view the so far four incidents of gravitational radiation from BBHs and their mergers/collisions. Not only has gravitational waves been validated, but also any lingering doubt re the existence of BHs.
    And I believe a Professor Bennett Link put your hypothetical to sleep a while back, did he not? (or was that the god?) apologies if I have you mixed up.
     
  16. paddoboy Valued Senior Member

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    As NotEinstein has asked, what do you you believe is left to exist, if we assume you are correct? It appears to me at least that if BHs did not exist, then something far more sinister and weird would be taking its place. Sometimes Rajish to be contrary just for the sake of being contrary, is not very productive.
    But hey, you knock yourself out...but please remember that arguing and/or claiming you have made a new found discovery, and/or invalidated some long held scientific theory, will not happen on any science forum open to all and sundry. From memory you did have a paper rejected, did you not? and of course Professor Link also rejected it. But if you are confident then you need to submit it for proper professional peer review with say arXiv....and of course accept their verdict, then go away and learn from it.
    This is also off topic for this thread, but hey! I don't really mind that. I'm just really interested in how you are still able to believe BHs do not exist after recent events.

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    ps: Your efforts over at "Cosmoquest" were quite admirable, even if finally rejected and invalidated. That's not meant as criticism by the way...I was truly impressed.

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  17. paddoboy Valued Senior Member

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    With regards to the OP, it's important to note that this isn't really the first time...Eta Carina comes to mind.
    https://en.wikipedia.org/wiki/Eta_Carinae
    Eta Carinae (η Carinae, abbreviated to η Car), formerly known as Eta Argus, is a stellar systemcontaining at least two stars with a combined luminositygreater than five million times that of the Sun, located around 7,500 light-years(2,300 parsecs) distant in the constellation Carina. Previously a 4th-magnitude star, it brightened in 1837 to become brighter than Rigel marking the start of the Great Eruption. Eta Carinae became the second-brightest starin the sky between 11 and 14 March 1843 before fading well below naked eye visibility after 1856. In a smaller eruption, it reached 6th magnitude in 1892 before fading again. It has brightened consistently since about 1940, becoming brighter than magnitude 4.5 by 2014. Eta Carinae is circumpolar south of latitude 30°S, so it is never visible north of about latitude 30°N.

    The two main stars of the Eta Carinae system have an eccentric orbit with a period of 5.54 years. The primary is a peculiar star similar to a luminous blue variable (LBV) that was initially 150–250 M☉ of which it has lost at least 30 M☉ already, and is expected to explode as a supernova in the astronomically near future. This is the only star known to produce ultravioletlaser emission. The secondary star is hot and also highly luminous, probably of spectral class O, around 30–80 times as massive as the Sun. The system is heavily obscured by the Homunculus Nebula, material ejected from the primary during the Great Eruption. It is a member of the Trumpler 16 open cluster within the much larger Carina Nebula. Although unrelated to the star or nebula, the weak Eta Carinids meteor shower has a radiant very close to Eta Carinae.
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    Another that appears to not know whether it is Arthur or Martha

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  18. paddoboy Valued Senior Member

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    More info on the OP.....
    http://adsbit.harvard.edu//full/1963PASP...75..133M/0000133.000.html



    and this.......Perhaps a TZO?? (Thorne-Zytkow object??
    https://en.wikipedia.org/wiki/Thorne–Żytkow_object
    A Thorne–Żytkow object (TŻO or TZO) is a conjectured type of starwherein a red giant or supergiant contains a neutron star at its core, formed from the collision of the giant with the neutron star. Such objects were hypothesized by Kip Thorne and Anna Żytkow in 1977.[1]In 2014, it was discovered that the star HV 2112 was a strong candidate.[2]
     
  19. RajeshTrivedi Valued Senior Member

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    You are able to fathom Planck level (1E-35 meter) but you are not able to fathom Quarks level (1E-16)?
    To reach at Plank level you have to go through Neutron Compression (Billions of Trillion times larger distance) and thats where energy release will ensue.
    And tidal gravity is not so strong at NDP level, and there is nothing like quarks "actually getting ripped asunder".
     
  20. RajeshTrivedi Valued Senior Member

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    This is taken up in paper, which you have accessed.
    https://www.academia.edu/34549343/Gravity_causes_release_of_Energy_in_Neutron_Star

    The object would be the Neutron Star at its maximum mass (around 3.24 Solar Mass).
    If you refer back to the paper it shows two radii R(s) and R(p), which are tabulated. R(p) is the point beyond which the innermost Neutrons will be compressed thus the point of start of release of energy. The table shows that for a core of Solar mass 3.24, the R(s) and R(p) are same, for smaller cores R(s) < R(P). That means if a Neutron star accretes and reduction in size takes place, then it will encounter R(p) first (before Schwarzschild radius) and thus release of energy and subsequent reduction in mass, so a Neutron Star can never become a BH by the process of accretion, at the best it will stabilize at the peak massed NS, that is around 3.24 Solar Mass (Incidentally that is TOV limit also).
     
  21. NotEinstein Registered Senior Member

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    When the distances between the quarks of different neutrons becomes comparable to the distance of the quarks inside a neutron, is it still a neutron? If you compress the neutrons down far enough, won't the neutrons break down at some point, just as atomic nuclei broke down during the formation of the neutron star?
     
  22. RajeshTrivedi Valued Senior Member

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    Yes, of course it breaks down.
    What happens when 940 MeV breaks down with just 12 MeV as rest massed quarks?
     
  23. NotEinstein Registered Senior Member

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    Ok, so the resulting object doesn't have neutrons at its core. What does it have then?

    I cannot parse that sentence; how can energy break down? What is "rest massed quarks"? Please rephrase it.
     

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