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Water into the sun

  1. Mar 15, 2005 #1
    i have a feeling this was answered a while ago. however, my problem is, a shere of water (as it is in space) is launched into the sun from here, assuming it hits no graviational feilds and continues on it's path into the sun, the following will happen:

    1. the water, frozen from its trip through space will melt and heat up
    2. the water will boil and evaporate to give up water vapor, still hurling twords sun at same speed
    3. ??? i do not know what hapens next, im assuming that the atoms split and enter the sun where the incredibly small amount of hydrogen fuels it for less than a fraction of a eccond

    can someone explain what happens in #3?
    i think one of my teachrs once told me that it catches fire. this makes not too muchsence seeing as there is no oxygen to do so, and even fire leaves residue so it ould just be left with H and O


    the long versoin of this; might we someday be able to fuel the dying sun by supplying it with hydrogen from other planets sometime in the distant future?

    seems extremely unlikely

  2. jcsd
  3. Mar 15, 2005 #2


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    You don't want to try to continually refuel the Sun. One, the Sun has a thousand times more hydrogen than Jupiter, and probably a few billion times more than the Earth. There simply isn't enough hydrogen around. Two, continually refueling the Sun will continually increase its mass. The increase in mass will increase both the temperature and pressure at the Sun's core, eventually causing it to collapse into a neutron star.

    Also, water in outer space does not freeze, it vaporizes. It boils violently. If you had a ball of water the size of a small planet, it would have enough self-gravitation to stay relatively intact, due to the pressures it would generate inside; without gravitation, the ball would simply vaporize and diffuse away, though its center of mass would continue along the original trajectory.

    The water molecules that eventually made it into the Sun would be split up into hydrogen and oxygen atoms, and the electrons would further be stripped from those atoms.

    "Fire" cannot exist in the Sun, because, paradoxically, the Sun is too hot. Combustion, the chemical process involved in fire, is the coming together of fuel and oxygen atoms into molecules, releasing energy. The Sun is so hot that it such molecules would be broken apart again by collisions.

    - Warren
  4. Mar 15, 2005 #3
    ok, ive heard this word a lot and i honesly dont know what it relly meens, vaporise, doesnt this men it will turn into a gas?

    frezing in space didnt seem to make sence either


  5. Mar 15, 2005 #4


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    Fueling the sun, huh? Interesting thought. The only reason I can think that one might want to do this is if the earth became uninhabitable and we wanted to live further from the sun (say on Mars or Pluto). Needless to say, this would be the least cost-effective way of solving the problem, but in theory it would succeed in making the sun brighter.

    However, if your goal is to increase the sun's lifetime, then you're actually better off removing mass. Adding mass will only cause it to exhaust its available fuel more quickly.

    Hydrogen would probably be stripped of its electron, but oxygen would be left with plenty to spare, probably just losing one. To strip all of the electrons from oxygen, you need extremely high temperatures (orders of magnitude higher than the solar surface).
  6. Mar 15, 2005 #5


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    Note that a comet is a nucleus of ice (and of course impurities as well) which throws off increasing amounts of water in the gas phase, the nearer it gets to the sun. The liquid phase of water is something that would not last long in space, as you probably already realize. My intuition tells me that a large ball of liquid water thrown suddenly into space would boil rapidly enough to chill the inner core enough to freeze, leaving you with a reduced-mass body, essentially a comet.

    I think there are known instances of comets hitting the sun. If I am right about that, then given sufficient starting mass, a chunk of ice could partly survive all the way into the outer perimeter of the sun.
    Last edited: Mar 15, 2005
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