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Space Science

Ion-Propulsion Craft Reaches The Moon 395

Posted by timothy 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."
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Ion-Propulsion Craft Reaches The Moon More

Ion-Propulsion Craft Reaches The Moon

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  • Warp ? (Score:2, Funny)

    by Killjoy_NL ( 719667 )
    "It ain't warp speed"

    But to me, it's a good step forward :)

  • Peak of eternal light (Score:5, Informative)

    by Rei ( 128717 ) on Monday November 15, 2004 @06:40PM (#10825113) Homepage
    I think what is most interesting is one of the destinations they're going to visit - the peak of eternal light [bbc.co.uk]. 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.

    • Re:Peak of eternal light (Score:5, Interesting)

      by binarybum ( 468664 ) on Monday November 15, 2004 @06:48PM (#10825193) Homepage
      man, screw your moon base. Perfect place for a five-star resort. This sounds like prime realty. The europeans should stake a claim to it and auction it off as land for when the moon is colonized. The price this would go for would probably fund a colonization project, oh and a moonbase - somewhere else.

      • Re:Peak of eternal light (Score:5, Informative)

        by RebelWebmaster ( 628941 ) on Monday November 15, 2004 @06:51PM (#10825214)
        I'm pretty sure there are international treaties banning any country from claiming extraterrestrial land for their country.
        • I'm pretty sure there are international treaties banning any country from claiming extraterrestrial land for their country.

          International treaties? BWAHAHAHAHAHA!
        • I'm also pretty sure that no one could do anything about it if the U.S. built a base and claimed to own 10 miles in every direction around it.
          • Sure they could. China could send up a "scientific mission" that just happens to fail and crash into the US Moon base. Do you really think the USA would start WWW (III/IV/V) over it? Humm, if the president at that time happens to be a Bush, maybe "we" would.

          • Re:Peak of eternal light (Score:5, Funny)

            by uncoveror ( 570620 ) on Monday November 15, 2004 @07:19PM (#10825436) Homepage
            No one on earth could do anything about it, but not everyone who goes to the moon is from earth. The Zhti Ti Kofft [uncoveror.com] would probably destroy any U.S. base in no time, or at least conquer it, and say ALL YOUR BASE ARE BELONG TO US!
          • You honestly think the US will remain the leading superpower forever?

            You poor thing.

            • Re:Peak of eternal light (Score:4, Interesting)

              by JudgeFurious ( 455868 ) on Monday November 15, 2004 @11:33PM (#10826987)

              Well of course nobody thinks the US will remain the leading superpower forever. Nobody who gives it any thought at least. At one point damned near ever real "power" on the earth was located in Europe. Now there's not a single nation in Europe that equals the United States. Together they do the job quite nicely though.

              That's just it. Despite what we've seen from the former USSR there is life after being a superpower. Most Americans aren't living under the impression that the ride's going to last forever and only the small percentage of real paranoids think it has to at any cost.

              I can't wait for us to return to being one of the pack so to speak. Then maybe our leaders wouldn't feel like it's necessary to station troops all over the planet. A military that can protect the United States is fine by me. An economy in the upper half of the world is more than many could ask for. Damn I'd like to see us get out of the world police business and back to the "working on making America better" business.
              • I think you're right, and I know it's off topic, but though I detest our present foreign policy, I don't want some other country to be a superpower either. Well, maybe some sane country like Norway or Canada, but China or India seem far more likely candidates.

                I think after USA falls apart, the world should get together and have a "no superpowers" rule. But then again, there were no superpowers at the 70 years ago, and things didn't turn out so well. Europe sort of punched itself out, somebody else took ov

                • Well, maybe some sane country like Norway or Canada,

                  And just how long would they remain "sane" when living with the status as "superpower"? How long before they too turned paranoid, or pissed off somebody and really got something to worry about?

                  Has there been studies on how even being targeted with nuclear weapoins for prolonged periods affects human psychology, and in the extent, foreign politics?

                  There was said something about how power corrupts.... Perhaps every state should have plans for how _not
              • Some comparisons
                • Currently European Union has more citizens (~400M) than United States (~280M), but US I think has younger population. Europeans aren't having enough immigration or kids.
                • European Unions economy is a bit bigger than US economy, but US has still more GDP per capita. US spends larger portion of its GDP on Defence (or Offence I guess now days), also Europeans have longer vacations and shorter work weeks that eat up the GDP a bit. Quality of life for citizens is hard to measure.
                • Europe doesn't
        • Country yes, corporation or person, no. Get up there and plant your stake, no international treaty is in your way.
        • <bushvoice>We'll see what my nukes say about that! ha!</bushvoice>

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

          Sorta. You're probably thinking about the Lunar Treaty [demon.co.uk]. While that treaty only prohibits the actions of states, I doubt that a private industry would be able to claim moon land with any authority. Still, Article 9 specifically grants the authority to build moon bases provided "that they do not impede the free access to all areas of the moon by personnel, vehicles and equipment of o

      • You can get that on Earth already. Where I grew up, just down the street from the North Pole, we had 3 months of daylight during summer. And plenty of water ice, if that's important to you.

        It's actually the one thing I miss the most. Once you've experienced life without any darkness, you realize how much the night cripples your life, and it's a hard thing to lose.

  • better article (Score:5, Informative)

    by teridon ( 139550 ) on Monday November 15, 2004 @06:41PM (#10825125) Homepage
    Nature has a better article here [nature.com].

    • Re:better article (Score:4, Funny)

      by macdaddy357 ( 582412 ) <macdaddy357@hotmail.com> on Monday November 15, 2004 @07:04PM (#10825322)
      That one's pretty good, but I think this one [rathergood.com] says it all.

  • Is it regular speed? (Score:5, Interesting)

    by xanthines-R-yummy ( 635710 ) on Monday November 15, 2004 @06:42PM (#10825129) Homepage Journal
    Does anyone know how the trip time compared other expeditions? I realize that the longer the flight, the more efficient and speedy this method would be, but I was just trying to get an idea of how fast this thing moves. Could cryogenics and this propulsion technology together land humans on other planets?

    • Re:Is it regular speed? (Score:5, Informative)

      by Rei ( 128717 ) on Monday November 15, 2004 @06:52PM (#10825224) Homepage
      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.

      • Re:Is it regular speed? (Score:5, Interesting)

        by bcrowell ( 177657 ) on Monday November 15, 2004 @07:50PM (#10825671) Homepage
        Apollo 11 took 73 hours from the burn that took it out of Earth orbit to the burn that inserted it into lunar orbit. This is actually very close to the time it would take to free-fall to the surface of the Earth from a distance equal to the radius of the moon's orbit. This is pretty much always the case with chemical rockets, which work by doing short burns followed by very long periods of free fall: the time to get there is the time it takes to orbit from here to there. To go to Mars, you can use Kepler's laws, and you find that the time to get to Mars in an elliptical orbit is 0.70 years.

        The problem with getting to Mars is fundamentally the radiation. If you send astronauts to Mars on a 0.70-year orbit, without any shielding against penetrating radiation, their radiation dose ends up being on the same order of magnitude as the dose that kills you. This is Not Good :-) There is a variety of ways to get around this:

        1. Use electromagnetic shielding. (There was recently a Slashdot article on this. The idea is to use a quadrupole field, which discriminates between high-mass and low-mass particles.)
        2. Use really thick material shielding. This requires either a really really really thick layer of rock, steel, ... (very heavy), or a really really thick layer of liquid hydrogen. Either way, it's a lot of mass.
        3. Cut the trip time dramatically.
        Solar-powered ion drive could make method #2 practical, because it would theoretically allow very large masses to be moved around without having to lift huge amounts of propellant off of the Earth's surface. However, a ship with a nuclear reactor aboard (not just a passive RTG) could accomplish both #2 and #3.

        Fundamentally, I don't see the justification for sending humans to Mars in the forseeable future. The really exciting science task would be to find out of there is unicellular life on Mars (with a positive result probably qualifying as the most important scientific result of the last 200 years). This can be accomplished with an uncrewed sample return mission.

        Want to send humans to Mars? Great! Please dream up either (a) a valid scientific reason, or (b) a valid commercial reason. I don't think either exists presently, and I don't think either will exist within the next 100 years.

        • Re:Is it regular speed? (Score:5, Interesting)

          by Rei ( 128717 ) on Monday November 15, 2004 @08:02PM (#10825741) Homepage
          The problem with all shielding methods proposed is that none that are lightweight handle GCR well. Electromagnetic shielding, mind you, does have some very promising applications concerning the Van Allen belts and other lower-energy particles. Right now, it looks like either liquid hydrogen or heavily saturated plastics (HDPE, for example) are going to be the best way to shield a craft on long trips.

          While I agree that there *currently* isn't a good reason to send people to Mars, I think that once we can demonstrate some cost-effective mix of ability to mine low-G bodies, grow realistic amounts of food outside of Earth, create bulk raw structural materials outside Earth, and to produce fuel outside Earth, there is ample reason to work on colonizing Mars. Not only would being able to do these reduce the costs of operation, but even high costs could be justified by the future-potential of using Mars as a triangle trade with Earth and the asteroid belt (one of the few things I agree with Zubrin on). So, I would argue in favor of working on the technology with the goal of eventually having it become a realistic course of action.

    • Re:Is it regular speed? (Score:5, Interesting)

      by centauri ( 217890 ) on Monday November 15, 2004 @06:54PM (#10825247) Homepage
      Could cryogenics and this propulsion technology together land humans on other planets?

      No, especially if you're aiming for extrasolar planets. Ion engines are good for a small payload that can take its time getting to where it's going. Humans (even those in some kind of imagined stasis) need something with a higher thrust to get where they're going in a reasonable time (ie, before cosmic radiation carves up their DNA, or a micrometeor holes their lifesupport system).

    • Re:Is it regular speed? (Score:2, Informative)

      by Metryq ( 716104 )
      Ion propulsion would be the last drive I'd consider for human transport. It is extremely low thrust, but can maintain drive for a very long time. Take a look at nuclear thermal rockets at nuclearspace.com. The book TO THE END OF THE SOLAR SYSTEM is an excellent primer on the technology and history.

      I think it was the TOS Trek episode "Spock's Brain" where Scotty commented on an ion-driven ship, "they could teach us a thing or two!" Right.

    • Re:Is it regular speed? (Score:4, Interesting)

      by purfledspruce ( 821548 ) on Monday November 15, 2004 @06:57PM (#10825270)
      The high radiation environment of space keeps us from using this method for humans.

      However, it would be quite useful to use this technology to bring cargo to the Moon for possible astronauts to use. For instance, it's possible to deploy an entire habitat--crew quarters, energy producer, perhaps even in-situ resource production ("mining" water-ice for oxygen and hydrogen to feul your return vehicle)--all before we launch humans on a high-energy tracjectory that will get them there in three days, thus avoiding high radiation exposure.

      You could do similar things with Mars. Here's a reference done by the Revolutionary Aerospace Systems Concepts part of NASA:

      OASIS [nasa.gov]

      It will take a suite of technologies to get safely to other planets, and possibly another suite of technologies to get back.

    • looks like this took quite a bit longer than the last trip to the moon but, IIRC, wasn't this same tech considered to keep Mir up in orbit? I thought they were considering bolting on a couple of Ion-Propulsion units and shuttle up some fuel ever now and then. I thought there was even a concept of a very long Ion absorbsion line they might extend down toward Earth to almost elimate the need for external fuel. Or I was just dreaming....

      LoB
    • Other people have pointed out that the Apollo missions got there in much shorter times.

      However, an interesting oddity is that the SMART mission averaged a significantly higher speed than Apollo did: It spiralled out from the Earth, and travelled around 80,000,000 km, according to the Nature article someone posted. Apollo went to the moon pretty much by the shortest route.

      Doing the math, I find the SMART average speed was around 8500 km/H, while Apollo averaged around 5500 km/H.

  • SMART-1
    BEAGLE-0

  • I don't get it (Score:4, Insightful)

    by centauri ( 217890 ) on Monday November 15, 2004 @06:42PM (#10825132) Homepage
    this method of propulsion could be ideal for travel in near-weightless space as it does not require any combustion to occur

    What were you trying to say here? That combustion rockets are not a good way to travel through space? Maybe they're not the best, but it's going to be some time before anyone seriously considers getting people to the moon with ion engines.

    • Re:I don't get it (Score:5, Interesting)

      by Headw1nd ( 829599 ) on Monday November 15, 2004 @07:05PM (#10825334)
      Ok.. the reason this is noteworthy, despite it's lethargic speed, has to do with reaction mass. Ion propulsion and rockets are similar in that both require reaction mass for propulsion- the craft goes forward because something goes back. The speed which the craft goes forward is proportional to the speed that something is ejected out back. Ion drives have ejection speeds far above that of conventional rockets, thus are far more efficient in their use of their propellant.

      So?

      So this is crucial on the long haul. With a reaction drive, when you run out of reaction mass, you're done. The craft becomes inert. The trick here is that the saturn V was out fuel within 15 minutes, wheras this craft is still accelerating a year later. Concievably, it could run for another year, or a dozen. (I don't know how much reaction mass it has) An ion drive craft might be made that could with enough reaction mass for an interstellar voyage, where a chemical rocket could not. (esp. considering the mass needed to decelerate at the ead!)

    • it's going to be some time before anyone seriously considers getting people to the moon with ion engines.
      Well, at least 13 months, at any rate.
    • I *think* what they were saying is that because there is constant thrust during the entire trip as opposed to a massive amount at just the very beginning, that constant thrust would in effect simulate gravity. This might be the intent, but the reality is it would be very low, and I would love to see someone calculate the actual generated g's.

  • So when do we get to see the US flag? (Score:5, Funny)

    by rsborg ( 111459 ) * on Monday November 15, 2004 @06:42PM (#10825135) Homepage
    On one hand, showing the US flag on the moon would make for very good press...

    [conspiracy] On the other hand, if they can't find it... [/conspiracy]

  • It REALLY Ain't warp speed (Score:5, Interesting)

    by guitaristx ( 791223 ) on Monday November 15, 2004 @06:45PM (#10825162) Journal
    Considering that Apollo 8 [wikipedia.org] made it around the moon in less than a week, and this mission took over a year, we're not dealing with lots of speed here.

    I'm interested in seeing some comparisons with project cost, energy consumption, etc.

  • How long will it take to reach Mars? (Score:4, Funny)

    by jerichohol ( 821580 ) on Monday November 15, 2004 @06:46PM (#10825174)
    Warp 0.0001 more like it, Picard would say"E....N.....G....A....G......E"

  • wrong link (Score:5, Informative)

    by Anonymous Coward on Monday November 15, 2004 @06:47PM (#10825184)
    it's http://www.esa.int/ [esa.int] not http://www.esa.in/ [www.esa.in]

  • Plasma technology is the space enabler (Score:5, Interesting)

    by QuantumG ( 50515 ) <qg@biodome.org> on Monday November 15, 2004 @06:49PM (#10825199) Homepage Journal
    Although it's called an "ion engine", it's really just the first step in the progression of plasma propulsion. Next up we have the VASIMR [nasatech.com] which they've been talking about testing on the space station. It can produce slow thrust like an ion engine, or it can produce hard thrust like a chemical rocket. You can power it with solar panels, or you can power it with a nuclear reactor. Eventually, almost the exact same design will be used in fusion rockets, and possibly even antimatter rockets. Then we're in Startrek country with plasma power distribution and ships which you can actually live and work on.

    • Re:Plasma technology is the space enabler (Score:4, Informative)

      by WolfWithoutAClause ( 162946 ) on Monday November 15, 2004 @07:22PM (#10825460) Homepage
      Next up we have the VASIMR ... it can produce hard thrust like a chemical rocket.

      'Fraid not. To do that requires an enormous, lightweight, electrical power source. No current powerplant, solar, nuclear, chemical or other can provide enough power to generate high thrust when used with VASIMR.

      VASIMR is a wannabe fusion power drive. Trouble is, fusion doesn't work well enough right now to use it for this; and they are stuck with trying to powering it the old fashioned ways. It works, but not noticeably any better than ion drive- if you were to get VASIMR to work with a new power supply, you can pretty much just gang up any of the existing ion drive thrusters and get about the same thrust.

      VASIMR has theoretical advantages of being able to vary the exhaust velocity to increase the thrust, but even on the lowest settings I've seen them talk about, ion drives usually give better thrust.

      • For some reason I think a 190MWt nuclear submarine engine would be more than adequate for heating plasma. There simply isn't a big enough dedication to making space colonisation happen. It's such a shame that we need militarisation to see innovation in technology.

  • Boeing has some power... (Score:4, Informative)

    by domenic v1.0 ( 610623 ) on Monday November 15, 2004 @06:52PM (#10825228)
    Boing has developed the PAS-5, the world's first commercial satellite with an ion thruster. [boeing.com]

  • This is not the first ion drive... (Score:5, Informative)

    by meringuoid ( 568297 ) on Monday November 15, 2004 @06:52PM (#10825234)
    ... JPL's Deep Space 1 [nasa.gov] 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.

    • 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.

      Yes, it really could make a difference. Specifically, it'd make the difference between how many times you'll have to say "great" before you get to the "grand-father was alive when they launched that thing" part of the conversation your descendants will have when it gets there.

  • Cheap Technology! (Score:5, Funny)

    by jd ( 1658 ) <`imipak' `at' `yahoo.com'> on Monday November 15, 2004 @06:57PM (#10825272) Homepage Journal
    Give me a Bussard Ramjet [woodmansee.com] any day! Well, that and an extremely good handbrake.
    • I think plasma sails [wikipedia.org] are more likely in the short term.
    • Actually, analysis of Bussard Ramjet showed that it is a good handbrake!

      Inspite of early promise it turned out that the thrust/drag of the ramjet against solar wind and interstellar gas turned out to be below unity. That's bad- you don't go anywhere.

      This lead to a concept called M2P2, which is an 'inflatable' plasma. You turn it on and it expands out to a few tens of kilometers, the solar wind pushes on it, and a few months later you are leaving the solar system at high speed, dragged along by the plasma

  • TIE Fighers? (Score:5, Informative)

    by ecliptik ( 160746 ) on Monday November 15, 2004 @06:57PM (#10825281) Homepage
    Isn't this how TIE Fighers from Star Wars worked? Their wings were solar panels, and TIE stood for Twin Ion Engine.

    • Re:TIE Fighers? (Score:5, Funny)

      by jfengel ( 409917 ) on Monday November 15, 2004 @07:09PM (#10825370) Homepage Journal
      That's right. What the movie doesn't make clear is that it was sped up by a factor of 10,000, because solar panels that size result in only a trivial amount of thrust.

      • Re:TIE Fighers? (Score:5, Funny)

        by mikael ( 484 ) on Monday November 15, 2004 @07:42PM (#10825618)
        That's right. What the movie doesn't make clear is that it was sped up by a factor of 10,000, because solar panels that size result in only a trivial amount of thrust.

        No, the TIE fighters had a large bank of 48 car batteries which were kept topped up by the solar cells. Each TIE fighter had to charged up from the mains at least once every 48 hours, otherwise the battery would run flat, and you'd be stuck in space. In that case, the only way to start the engines was to plug an R2D2 unit into the cigarette lighter socket.
        • What the hell is an "R2D2" unit??? "R2D2" was an individual "R2" unit with the designation "D2".

          Now, somebody needs to explain how the maximum number of R2 units with unique ID's in the WHOLE FRIGGIN' GALAXY could only have been 1296???
    • Isn't this how TIE Fighers from Star Wars worked? Their wings were solar panels...

      "Luke, you may get away today, but in 12,000 years my total thrust will eventually exceed yours, and you'll be MINE!" -- Darth "Quickie" Vader

  • Sharper Image (Score:3, Funny)

    by nick_davison ( 217681 ) on Monday November 15, 2004 @06:59PM (#10825291)
    Anyone who's anyone knows Sharper Image have been selling these for years.

    There's really no end to the crap Sharper Image can add ions to and double the price for. It only stood to reason they'd release spaceships with them too. ;)

    You'll find them in their catalogue next to the negative ion vacuum cleaners, negative ion air purifiers, negative ion hair driers, negative ion bikini zone razors, and negative ion pet hair brushes (the scary thing is I only made one of that entire list up).

  • Science writing at its best (Score:5, Informative)

    by peggus ( 749983 ) on Monday November 15, 2004 @07:03PM (#10825317)
    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....

  • How is weightlessnes relevant? (Score:5, Interesting)

    by mowler2 ( 301294 ) on Monday November 15, 2004 @07:05PM (#10825333)
    I dont understand why they talk about the probe being (near) weightless in space in the same context as the engine beeing useful in space?

    No matter where the probe is, it has got the same mass, and hence the same inertia. Low-thrust engines work good in space because of no friction and often no requirement on quick travel (if it is a non-manned spacecraft). On earth an ion engine would never work for several reasons, one beeing friction against air and ground, but none of them has to do with the weight of the vechile/probe?

    Or have I misunderstood something?
    • Newton's law of universal gravitation: Fg = GMm/(r^2) where:
      Fg is the force of gravity
      M is the larger mass
      m is the smaller mass
      r is the distance between the center of hte two objects.

      An object at the surface of the earth with a mass of 1 kg is subject to a gravitational force of 9.8N. At the moon, the gravitational force exerted by the earth on the 1kg mass, using newton's law of universal gravitation is 0.0026N.

      So indeed, gravity and weight have a pretty big part to play in this. On the surface of the
    • I think they were implying that you couldn't use one of these engines to get off the earth's surface. The thrust they generate is on the order of the weight of a single sheet of paper. If you don't have to fight earth's gravity to get the craft moving, you're set. If you're trying to get off-planet, you're not going anywhere.

      JPL has an open house every year. A few years back, they were in the middle of a multi-year burn test and during the open house, you could see the engine's blue glow as it sat there chu

  • NASA announces it will outdo the ESA (Score:5, Funny)

    by i41Overlord ( 829913 ) on Monday November 15, 2004 @07:09PM (#10825367)
    "After hearing the news that the ESA's slow ion-powered probe has entered Moon orbit after a record-long 13 month voyage, NASA has announced that it will launch an even slower probe that propels itself by gliding on a trail of its own mucous."
  • JP Aerospace has proposed [hobbyspace.com] using an ion drive to take a special purpose blimp orbital.

    What is interesting about this approach is the high ISP might make space fairly cheap. Personally, I find the fact that travel using this means is slow somewhat interesting. Humanity might benefit by having some "wide open spaces". Communications inside the solar system would be rapid in any event. Slow transportation might act to help discourage things like rash, interplanetary wars.

  • Technical project info (Score:4, Informative)

    by d2ksla ( 89385 ) <krister AT kmlager DOT com> on Monday November 15, 2004 @09:18PM (#10826278) Homepage
    The project home page can be found here: http://www.ssc.se/ssd/smart1.html

  • Ion propulsion for cars! (Score:4, Funny)

    by cpghost ( 719344 ) on Monday November 15, 2004 @09:22PM (#10826303) Homepage

    Imagine ion propulsion in our cars! Just gimme some months to reach those 55 mph...

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