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Stoping the desturaction of the sun?

  1. May 4, 2006 #1
    In about 5 billon years the sun will become a red giant. Would it be possible to stop with furtristic (super extrme) technology. Like by putting more hydorgen in the sun or somthing.

    It might be possible assuming that if were still alive that we could have the technology to that five billon years(just think of what computers would be like in five billon-superfast and superpowerful...but it still gets spam:frown: )
     
    Last edited: May 4, 2006
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  3. May 4, 2006 #2

    chroot

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    If you could inject hydrogen into the sun's core at the same rate it was being consumed, you could prolong the sun's main-sequence lifetime by a significant amount of time. The added mass would eventually cause some changes, but they would take a long, long time.

    Keep in mind that injecting hydrogen into the sun's outer layers won't do anything at all; even as the core begins to shrink because of diminishing fuel supply, the rest of the Sun's envelope is still mostly hydrogen. You'd need to get those protons into the core itself.

    Good luck!

    - Warren
     
  4. May 4, 2006 #3

    Astronuc

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    It is highly unlikely that humans would have such technology. As for the hydrogen, where would one obtain such quantities of hydrogen? Jupiter? and Saturn? How much energy would need to be expended to move that mass to the sun? The pressure on objects close to the sun is enormous.

    Adding a lot of additional mass to the sun would also increase its gravitational pull. Earth might get a little too warm. :biggrin:

    Computer speeds will eventually saturate.
     
  5. May 4, 2006 #4
    In five billon years we could have that kind of technology.
    It's the most common element in the unvierse thare billons of stars I think in five billon years we might be able to extract hydrogen form other places in the universe.
     
  6. May 4, 2006 #5

    SpaceTiger

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    To really extend the sun's lifetime, your best bet is just to strip off something like half its mass. Assuming it then settles onto the main sequence, the sun effectively becomes an M star with a much longer lifetime (approximately five times longer). Of course, M stars are much dimmer -- a move to Mercury might then be in order.

    All in all, I suspect it would be easier to just move to another star system. Any civilization with the ability to strip off half the sun's mass ought to be able to make a simple interstellar trip.
     
  7. May 4, 2006 #6

    dav2008

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    I think we have more important things to worry about before the sun becomes a red giant like losing our atmosphere. How long is that supposed to take?
     
  8. May 4, 2006 #7

    SpaceTiger

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    Perhaps the earth scientists will have a better feel for this. Assuming a Maxwellian velocity distribution, one can compute the fraction of molecules of a certain mass that exceed the escape velocity as a function of time, but this is not the only process occurring. There are many feedback processes, including volcanic activity, evaporation, respiration, pollution, comet/asteroid impacts, and solar wind injection. There are also other means of depleting the atmosphere, including condensation, rainfall, and tidal stripping. I suspect the answer is not well known.
     
  9. May 4, 2006 #8
    I think everone is misunerstanding my question. I'am asking is it possible to stop the desturction of the sun not the earth. It's really about stars in genreal. I'am just using the sun as an example since it's the star we know most about.
     
  10. May 4, 2006 #9

    SpaceTiger

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    Does the first part of my post not answer that question, or did you want the sun to live indefinitely? All stars will run out of fuel eventually, some just take longer than others.
     
  11. May 4, 2006 #10

    As he said, strip off the mass. Though I don't know that this would necessarily work. See, when a low mass star forms naturally, from a gas cloud, it has a very long life span. However, if you were to instantly remove 50% of the sun's mass, it would expand rapidly due to a far larger pressure gradient than the amount that creates hydrostatic equilibrium. The remaining matter should still be gravitationally bound, but it would expand outwards rapidly at first, with unpleasant consequences for anything in the path. That said, once it reached equilibrium again, it would last much much longer. Of course, you could remove the matter slowly enough to keep the sun always close to equilibrium, which avoids this problem, but would probably take a very long time.
     
  12. May 4, 2006 #11

    SpaceTiger

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    I'm not clear on why you think this is a problem. Are you suggesting that it would expand past 1 AU and envelope the earth?
     
  13. May 4, 2006 #12
    Yes it does answear question.Thanks.
     
  14. May 4, 2006 #13
    No, I have no idea how far it would expand off hand, and I won't venture a guess either because it would just be a shot in the dark, though I suppose it wouldn't be too hard to calculate an order of magnitude estimate of peak volume. I was merely pointing out that if you were to instantly remove the matter, it would expand, and probably rapidly. Not that it matters since you can't instantly remove the matter anyway. But since this entire discussion is an entirely hypothetical exercsize, I thought I'd point it out.
     
  15. May 5, 2006 #14

    Astronuc

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    Your asking is it possible for organisms to directly influence stellar evolution.

    I strongly doubt it!

    As ST indicated, if mankind had the technology to influence a star (sun), then interstellar travel would be possible . . .
    . . . which is what your solution would require.

    Your basically suggesting that mankind would have technology to go somewhere else in the Galaxy - grab a star (a very massive object) or a HUGE quantity of hydrogen (say an amount on the order or Jupiter or perhaps 10 Jupiters) and bring it back to the sun!

    Um . . . . NO WAY!

    It would be more efficient to find a similar star - or move the Earth. But then the Earth would get pretty darn cold way out there in interstellar space.
     
  16. May 5, 2006 #15

    chroot

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    It's true, it'd be easier to send thousands of tons of human beings to settle another star system than it would be to bring hundreds of thousands of tons of hydrogen back to save our own star.

    Another fact, perhaps worth considering, is that stars still have an enormous quantity of hydrogen left even as they're dying. The hydrogen is just stays in the envelope of the star, even while the core is becoming more and more depleted and is collapsing.

    If there were simply a way to "mix" the star a little more effectively, pushing fresh hydrogen fuel from the envelope into the core, you could extend a star's life by an enormous amount.

    - Warren
     
  17. May 17, 2006 #16
    In 5 billions years (theoretically assuming our species can even possibly survive that long) human civilization would be so advanced that it would make today's civilization look like a small bacteria colony. So yeah, I think by that time we would be able to ignite our own stars.
     
  18. May 20, 2006 #17
    Every one seems to be unaware of the fact that for every 1 billion years the sun will get 10% brighter... in the net 1 billion years earth will no longer be habitable... much the same as venus is now and mars will be our bet. The billion years after that mars may become to hot and europa around Jupiter or Titan around Saturn will be the place to live.

    lets consider the time period we are thinking here for a moment...

    1 BILLION YEARS

    The length of (...time since) life on earth is 3.5 billion years
    The length of multi-celled organisms 3000 million
    The length of none ape human like primates... ~5.4 million years
    The length of Homo Sapiens 120000 years
    The length of recorded history ~11000 years
    The length of sophisticated technology such as agriculture 10000 years
    The length of time since the industrial revolution 250 - 300 years
    The length of time since the computer revolution ~30 years

    Now lets move forward, considering technolgies such as nano, genetic, space, energy, checmical, and disciplines none of us have even imagined yet it is not hard to say that assuming humannity does not blow itself up or get destroyed by an outside force we have 100s of millions of years to evolve...

    That being said we will not always be as we are now (evolution baby) but we will still use technology and that will also evolve it is not unreasonable to think that we will have the technology to move entire galaxies one day in the furture given the rate of progress we have seen the last two hundred years and the speed that that progress is increasing.

    if we have the inclination to do it is another thing all together.

    So in believing we will have the technology to transport hydrogen to and from the sun...

    A slow and gradulal shift from the sun's outer layers that replenishes the sun's core will not only save on the mass change problem that introducing new hydrogen into the sun would produce it will allow the sun to last a great deal longer, say for whatever reason who knows huammnity could become nostalgic about earth and our solar system and decide to keep on trying to save it, after the sun's own hydrogen has been depleted a method for removing the heavier elements up to iron from the sun's core will need to be established and then extra hydrogen will need to be added in order to maintain its current state, other unknown forces may act on the sun that we do not currently know about and still other cosmological events, such as the Milkyway Galaxy on a collison course with the Andromeda Galaxy may cause other problems but given a closed situation free from external influence using the elements available in the solar system only, we could pro long the life span of the sun but we will not be able to prevent it from dying unless we master alchemy and can convert iron back to hydrogen... a possibility maybe with nano-technology.
     
    Last edited: May 20, 2006
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