Ice fuel for rockets...

Discussion in 'General Science' started by cmartinez, Mar 17, 2015.

  1. cmartinez

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    Jan 17, 2007
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  2. alfacliff

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    why not? ice is denser than gaseous fuel, or liquid fuel, more fuel in a smaller space. those cubesats are small, not much room for fuel. some engines are even using small arc's to vaporize metal used for fuel. an ion engine using a gas is ineficient, you have to heat the gas to keep it from liquifying or freezing, and to keep it pressured.
     
  3. cmartinez

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    I didn't mean to imply that I didn't like the technology... in fact I think it's an excellent idea. My observation was rather that it is going to be used in micro-satellites, and that those small satellites could become a hazard for generating space-junk. I think we're in the verge of heavily polluting the earth's orbital space... and we don't even know how to clean it yet!
     
  4. alfacliff

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    another problem with the microsats is that a lot of them are using ham radio frequencies without any ham usage. kind of clutters up the somewhat crowded bands. mostly around 145.7mhz and in the uhf 70 cm band.
    the Fcc (icont know why them) already requires ham radio satelites to have a de-orbit motor to kick them out of orbit, dont know what the commercial cubesats have to do.
     
  5. Kermit2

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    NORAD currently tracks all space debris in orbit, what difference will a few more bits make in a field of thousands and thousands already there?
     
  6. cmartinez

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    It tracks debris down to a certain size... then again, tracking debris doesn't really solve the problem. One of these days an event of some magnitude is going to force the space agencies to develop a viable form of collecting or disposing of that debris.
     
  7. shortbus

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    Are you talking about a "bird strike" in space? http://en.wikipedia.org/wiki/Bird_strike
     
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  8. cmartinez

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    Something like that yeah... but in this case it would be called a "cube strike"... and have the consequences shown in the movie "Gravity"
     
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  9. alfacliff

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    at least the cubesats design standards are for smaller satelites, imagine having refrigerator sized satelites zipping around in low earth orbit. even sputnik 1 was one meter in diameter.
     
  10. GopherT

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    Lets see, what's more dangerous?
    - a satellite full of hydrazine falling to earth, (1:10,000 risk to human life) or,
    - blowing it up in a low earth and letting the debris risk all future space craft.

    What would you do?

    What did nasa do?

    Well, they called the US Navy, of course.

    Here is the story, from IEEE Spectrum
    http://spectrum.ieee.org/aerospace/satellites/us-satellite-shootdown-the-inside-story


    Here is the simulation of debris
     
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