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Ion-Propulsion Craft Reaches The Moon

Posted by timothy on from the not-landing-just-saying-hello dept.

Rollie Hawk writes "It ain't warp speed, but it's exciting new technology at work! The European Space Agency put an ion-propelled rocket into lunar orbit today. While not much horsepower is generated, this method of propulsion could be ideal for travel in near-weightless space as it does not require any combustion to occur."

9 of 395 comments (clear)

  1. Peak of eternal light by Rei · · Score: 5, Informative

    I think what is most interesting is one of the destinations they're going to visit - the peak of eternal light. Perfect spot for a moonbase - constant sunlight instead of 2 weeks of light and 2 of darkness, water ice likely in nearby craters, and temperatures warm enough that you might be able to get by with passive solar heating alone.

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    Nobody pushes buttons like our bunny. Big red buttons with labels that say "IGNITION", apparently.
    1. Re:Peak of eternal light by RebelWebmaster · · Score: 5, Informative

      I'm pretty sure there are international treaties banning any country from claiming extraterrestrial land for their country.

  2. better article by teridon · · Score: 4, Informative

    Nature has a better article here.

    --
    I hold it, that a little rebellion, now and then, is a good thing. -- Thomas Jefferson
  3. wrong link by Anonymous Coward · · Score: 5, Informative

    it's http://www.esa.int/ not http://www.esa.in/

  4. Re:Is it regular speed? by Rei · · Score: 5, Informative

    Well, apollo took a little over 3 days to accomplish what this craft took a year to do. And it's not neessarily "the longer the flight, the more efficient and speedy this method would be". It's all about ISP. The faster the "exhaust" leaves the craft, the less mass of propellant you need to achieve a given delta-V - and it falls off fast.

    In fact, ion drives tend to be rather energy-inefficient. However, they get their energy from electricity, which is renewed either by solar or RTG energy. Since RTGs are extremely energy-dense compared to conventional fuels, and solar cells constantly take in more energy, the penalty for a large amount of electrical waste and much, much larger propulsion system (for a given amount of thrust) is dwarfed by the benefits in terms reduced propellant mass.

    --
    Nobody pushes buttons like our bunny. Big red buttons with labels that say "IGNITION", apparently.
  5. Boeing has some power... by domenic+v1.0 · · Score: 4, Informative

    Boing has developed the PAS-5, the world's first commercial satellite with an ion thruster.

  6. This is not the first ion drive... by meringuoid · · Score: 4, Informative
    ... JPL's Deep Space 1 demonstrated the potential of such an engine back in the 20th century. Now we're seeing the first missions to rely on ion propulsion.

    It'll be interesting to see, if the Pluto probe ever flies, whether that uses ion propulsion. An ion drive could really make a difference on such a long-haul flight.

    --
    Real Daleks don't climb stairs - they level the building.
  7. TIE Fighers? by ecliptik · · Score: 5, Informative

    Isn't this how TIE Fighers from Star Wars worked? Their wings were solar panels, and TIE stood for Twin Ion Engine.

  8. Science writing at its best by peggus · · Score: 5, Informative
    The engine does not combust fuel; rather it splits atoms with electricity to get ions, accelerates them at high speed, and then ejects them, driving the spacecraft forward. SMART-1 generates its electricity by converting sunlight with outsize solar arrays that give the spacecraft a 45-foot wingspan.

    Brilliant science journalism there. If the smart probe was splitting atoms it wouldn't need solar panels. Not to mention you don't need to split atoms to get ions.

    That reminds me of the article that was written on some research I was involved with. We were pulsing cells with high potential electric fields. The field strength was measured in MegaVolts per meter due to a very small gap between the electrodes, the actual voltage was only a kilovolt or so (over a 300ohm load for 5-15 ns). The journalist / engineer-reject thought that megavolts sounded really big and took it upon herself to proclaim that our pulse generators could power a whole city. Moan, groan....