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Important question! (possible end of the world scenerio?)

  1. Mar 13, 2012 #1
    yeah, sort of, but im unsure.

    So Is that possible, that supernova explosion of a star will cause another ray of fast moving stuff like photons, which is focused, so it has damaging effects far away from the stellar system?

    like for example there re at least 1000 of such stellar systems where there is a hot jupiter in it, and these are all edge on to earth, so sometimes the the hot jupiter "is" between us and the star. i think that the hot jupiter might change cause of the energies from the rays of supernova, sine it might be close enough to get enough concentrations. The changed material of the planet might eihter focuse some wavelength, or the secondary nuclear reactions starting from one surface of HJ interacting with the farther away part of waves of the star somehow result in focused beam.

    Was that considered by some, simuklated its piosibilities based on data available or such? is it possible by theory?
  2. jcsd
  3. Mar 13, 2012 #2
    Your whole idea of a 'hot Jupiter' getting in the way of its parent star and somehow refocusing light to cause harmful effects here, albeit change anything at all, is completely wrong. No chance at all of happening.

    However what you first said is sort of possible. If a close (in galactic terms) star went supernova, it could potentially do a lot of damage. Supernovas create a lot of x-rays and gamma-rays, and both are harmful in large enough quantity. I have heard the claim that were Betelgeuse to go supernova (a very large star that is also very close in galactic terms-20 light years), it would create enough of these ionizing particles to potentially cause severe environmental damage, possibly even of an apocalyptic level.

    However, there is absolutely no signs that this will happen at any point in the near future (and this is the near future as far as stars go-a long, long time for us), and so most likely when this does happen the human race will be long gone.
  4. Mar 13, 2012 #3


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    Picture a gnat (Jupiter) in front of the world's biggest floodlight. Jupiter isn't going to affect what happens on earth. Supernova Effect on Earth
  5. Mar 13, 2012 #4


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    It is possible that this could occur, but extremely unlikely that it would be damaging. The nearest stars that are close to going supernova are far enough away that they would not have any major detrimental effects.

    If anything these planets would absorb energy from the supernova, protecting us. (Even if it is just a miniscule fraction of the energy) The gas giant would absorb high energy gamma and x-rays, not focus them.
  6. Mar 13, 2012 #5


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    Betelgeuse is about 640 light years distant, not 20. It does not pose a threat to life on earth.
  7. Mar 14, 2012 #6
    Vorde: u said that something going supernovae 20 light years away can cause us possibly apocalipse (something big). energy density ű(ok to call that pressure?) decreseases with the squrare of the distance. so compare the position of the hot jupiter to 20 light xears apocalips, and i say the hj is desintegrated near it. Someone else sais the opposite, it will just absorb.

    Because of that vaguenesss of answers, i still cant decide. Plese if someon can, calculate the distances between atoms in hj, calculate energy density of supernovae waves, estimate backed up by calculations, thaat what would happeb to the hj, , aand how would it react, also, the length of the major wavefront of the red giant has to be known. (thats since im not a physicist).

    But any rate, back up ur claims and conclusions at lest with one layer of stugff - which serve as basis for ur conclusion. Btw, i didnt call the title apocalipse, accidentally. most of science people have a strong prejudice against apocalipse theories, i hope its not the decisive factor for ur answer.

    EDIT: based on Vordes claim about 20 light year betelguse causeing dmage (it ionises splits some atoms, but enough tpo cause big trouble, reduced the supernova energy output by half (possibly a general kind of supernova). That kin of star would create same near/apocalipse, ionisation splittinggarbage at 14 lightyears. Many of such stars has hot jupiter (as far as its the average giant star?) in wikipedioa its stated, 75 * 10^6, i increased that to 9 * 10^7, a light year is 9*10^12 (so to give smaller numb in comparison. So near apocalipse distance is 1400000 times farther then most hot jupiter so compared to apocalipse ionisation, at hj ssurface when supernova, its 1960000000000 time larger energy density, and i think hj hs much mettallic hydrogene and other light gases, and i think if the 20 light year apocalipse energy is correct, then a hj would experience massive fusion pulses in its hidrogen mantle. Since its in the metallic state it has peculiar characteristics regarding propagating some waves. Again the fusion starts at the "surface" of thehj, now draw it and u swill see, thatat given right ratio of processes, there will be focused emissions (but only if 20 lightyear apocalipse, and the extimated supernova outpu of average giant/hot jupiter system is right)
    Last edited: Mar 14, 2012
  8. Mar 14, 2012 #7
    Disregard where I said 20 light years, I followed that claim back to a news article from a non-scientific publication, that number is incorrect. Your science is messy and disorganized so I cannot follow it, but I can promise you a Jupiter size planet orbiting a supernova would not make a noticeable difference to us.
  9. Mar 14, 2012 #8
    i dont know howdisorgannised. anyway, i just took the claim, that such a starmight be hurtfull from 20 lightyears, then assuming the energy waves are gouing in every direction (sphere) i calculated how much denser (apocaliptic energy units/ per square kilometer since we were not taliking joules :P) it ould be at a far hot jupiter position. that is all. I dont know if supernova is ring or just some secondary waves are created i a ring shape as the star had a spin).

    Anyway, so if thats untrue whatever, but please someone do some calculations, using energies ofsupernovae (calculating why it shouold have so much energy/performance etc).
  10. Mar 14, 2012 #9
    You might be interested in the book "Death from the Skies", by Phil Plait. It covers various apocalyptic scenarios, and discusses the dangers and odds surrounding them. Read this, and supernovae may not be your biggest worry any more. :)
  11. Mar 14, 2012 #10
    You can actually calculate what would happen to a Jupiter-like planet if it absorbs the spectra of a supernova. I am not going to attempt it myself, but my instinct is that it will actually lower the wavelengths of photons it absorbs.

    Why? Because our sun's core produces very energetic photons, but they are absorbed and emitted so many times before they reach the surface that the effective surface temperature of the sun is relatively low compared to what nuclear physics predicts the temperature in the core should be.
  12. Mar 14, 2012 #11


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    I'm sorry, what exactly are you asking? Please be as specific as possible. You're grammar and spelling isn't that great and I'm having a hard time following you. Do you want to know if there are any stars close enough to us to harm us in the event of a supernova? Or if your hot jupiter idea works? Or what?
  13. Mar 15, 2012 #12
    ok, lets forget everyithing in this thread and start over - i will be as specific as i can be.

    i explain too, how i come to that thought.

    I was thinking that a very dangerous apocaliptic thibg would be somethin which moves very near or at the speed of light. I dont know if there are aliens out there, so i dont consider it, but there are stars, which sometimes go through a supernova explosion, releasing a lot of energy under a small period of time. I know that the spatial density of this energy wave thing drops rapidly with disstance from the sar. In fact, if the energy release from the star is aproximately equal to every direction in 3d space, then the spatial energy density will drop with the square of distance away from the star. Thats very rapid, so i think it probably wont cause harm on its own. BUT, it might evaporate a planet or change it, so the planet become either a lense or a lens and a secondarywave source. Think about it, the energy waves reach that hot jupiter on one side first, so if it starts a nuclear fusion (much hidrogen in the HJ ) it might go very rapid (since the performance of supernova is gtreater then for example a burning star). that fusion might cause moving of particles which canat leaast generate long waves. the hj mantle in itself is permeable to some not so low but not so high frequeny electromagnetic waves. then if these waves start out not from inside but on one side of the hj (where the supernova hit), they will leave the hj mantle on the other side (all relative to the normal of surface piont where it left it). then as the vacuum has different permeability for waves, the hj mantle, rays woill difract, like in a lense.

    that fusion on one side means some number of earth amount of hydrogen fusing, at once pretty much. IO would like to know is that possible, with the energy output/performance of a supernova, and the distance of a regular hj, or small star? Please back up utr claims with calculations.
  14. Mar 15, 2012 #13
    It's not so much we have to prove that a exoplanet would not refract the waves of a supernova, where are your calculations that they would?
  15. Mar 15, 2012 #14
    Just a few thoughts.

    1) Supernovas are not necessarily isotropic.

    2) Nuclear fusion is sustained in stars due to gravity. Even if a supernova caused nuclear fusion within a planet, it would likely puff out and could not sustain a chain reaction. Chain reactions are required for sustained nuclear fusion which is why you cannot build a hydrogen bomb simply by packing a fission bomb with H2.

    3) Even if all the mass of Jupiter suddenly released its energy in the form of a fusion explosion, the total energy released would be far less that that released by a massive star undergoing a core-collapse supernova.

    I am not going to back this up with calculations simply because I have enough of my own to do at the moment. If you want to figure it out for yourself, look up the energy released in a proton-proton chain reaction or the triple alpha process. Then, calculate the energy released if every atom of hydrogen in Jupiter went through that process. That is the absolute maximum amount of energy release possible. I think you will find that it is at least a magnitude lower than the smallest core-collapse supernovae.
  16. Mar 15, 2012 #15


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    Mzoltan14, I'm sorry but that simply isn't possible.

    1. I think your view of a supernova is a little off. While a supernova releases a tremendous amount of energy, this does not happen in seconds or minutes. Supernova 2011fe happened on 24 August 2011. It's peak magnitude, which corrosponds to the light released from the event, was +9.9 on 13 September 2011. I just took a picture of this supernova in January and while it is less visible than before, it still shows up clearly. So the energy of the supernova is released over months of time, much of it from decaying isotopes that were created in the shockwave. So this energy isn't so much a "blast", but more of a sustained glow.

    2. A gas giant planet does not focus the radiation from the supernova. Instead it absorbs much of the radiation that falls on it.

    3. As mentioned above, a fusion reaction requires sustained pressures to contain it. With half of the planet experiencing no force from the explosion, there will be no way to confine the gas at a high enough pressure and temperature required to blow the planet apart. At worst the planet experiences a tiny amount of reactions and is vaporized by the event.

    4. Even the largest gas giants are absolutely tiny compared to the stars that go supernova. Jupiter is 0.1% of the Sun's mass and the Sun is by far too small to go supernova. So, even IF there was some way for the planet to explode the energy released would be many orders of magnitude lower than the energy released from the star itself. So it's like a artillery shell hitting you at the same time that the blast from a thermonuclear bomb at close range does.
  17. Mar 15, 2012 #16
    On the other hand, you can start worrying about meteors...which are far more likely to impact us (Far more likely than zero in this case).

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