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Ion Engine Propels Probe to Moon

lenin writes "The BBC is reporting that Europe's first moon mission, SMART-1, appears to be a success thus far. It also talks about the low-cost technology being used and the charged xenon (ion) propulsion system. Can TIE-fighters be far off?"

34 of 330 comments (clear)

  1. Tie fighters by panurge · · Score: 4, Funny
    If Tie fighters had the acceleration of the Smart-1, Lucas Skywalker would have had nothing to fear. There's obviously some sort of competition on for the slowest flight to the Moon. The acceleration is even lower than that of the Smart car.

    Yes, I do know why ion engines are a good idea. Just leave Star Wars out of this.

    --
    Panurge has posted for the last time. Thanks for the positive moderations.
  2. TIE by CGP314 · · Score: 5, Funny

    It also talks about the low-cost technology being used and the charged xenon (ion) propulsion system. Can TIE-fighters be far off?

    Yup, that's how technology goes, straight from moon probe to TIE fighters. No intermediate steps necessary. No life support, no radiation shielding, necessary. I can't wait to buy my A-Wing.

    1. Re:TIE by gl4ss · · Score: 4, Funny

      dude, tie fighters don't have life support(the pilot needs a full space suit)! that's why they're so cheap at your local imperial clearing sales.

      geez, the people on slashdot these days!

      --
      world was created 5 seconds before this post as it is.
  3. Obligatory. . . by Limburgher · · Score: 4, Funny
    "But Ion engines can never acheive fast accelleration"

    (sigh) Then the Emperor has already won.

    --

    You are not the customer.

  4. elevator by spectrokid · · Score: 5, Funny

    If we combine this with the space elevator, we can send shit to the moon on 6 AA batteries!!!

    --

    10 ?"Hello World" life was simple then

  5. Re:Its about time. by dex22 · · Score: 5, Insightful

    Russia does far more launches than the US.
    Russia does them much more safely. In manned launches, they have something like a 99.9% success rate (one launch mishap in over 1000 launches). The US has had two mishaps in about 115 launches.

  6. Re:Ooh, IONs by puetzc · · Score: 5, Funny

    Of course you don't understand - after all, this time it really IS rocket science.

  7. Re:Ooh, IONs by quasi_steller · · Score: 4, Informative

    (Frankly, the physics of using rockets in space has never made sense to me - how do they go anywhere? - but it seems to work, so that's fine.)

    Rockets use the same priciple that ion propulsion uses, the law of action and reaction (one of Newton's Laws, can't remember which one off the top of my head). Basically matter is accellerated out the back of the engine (by chemical means in the chemical rocket engine, and by using electro-magnetic forces in the ion propulsion engine). This accelleration causes causes a force to be placed on the engine that is equal to, but oppisite in direction, to the force accellerating the matter.

    To answer your first question, Deep Space 1 used ion propulsion.

    --
    ...interesting if true.
  8. Re:Ooh, IONs by BTO · · Score: 3, Funny
    Frankly, the physics of using rockets in space has never made sense to me - how do they go anywhere?

    It's pretty simple, really. In the atmosphere, rockets work by pushing against the air, as you might expect. However, when the rocket leaves the atmosphere and enters a vacuum, or what we physicists call an "inertial frame," then your thrust is pushing against this inertial frame, which is kind of like what physicists used to call the "Aether." Aether has gotten a bad name, since Einstein proved that electromagnetic waves don't need to travel in the aether, but this has led to the misconception that aether doesn't even exist. Mach's principle shows that Aether is real, since it is what we need to push against to rotate and accelerate in space.

    --

    Banach-Tarski Overdrive
  9. Re:Ion drive is cool, but... by lurker412 · · Score: 3, Insightful

    What's the hurry? The moon will keep. Think science, not Star Wars.

  10. Friction by RetroGeek · · Score: 3, Insightful

    Can TIE-fighters be far off?

    There will be no TIE fighters until we have friction in space. To be able to turn like an airplane in an atmosphere you need something to react against.

    --

    - - - - - - - - - - -
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    1. Re: Friction by shoemakc · · Score: 4, Interesting

      There will be no TIE fighters until we have friction in space. To be able to turn like an airplane in an atmosphere you need something to react against.

      AFAIK, space isn't a perfect vacuum, there is matter in space, just that it's concentrations are extraordinarily low. You'd need either a very large control surface, or some method of increasing friction over what limited matter there is. Why do we use brake pads on a car and not say, bars of moist Ivory? Same reason.

      Also, there is also free energy in space...particularly in a solar system. I'm not sure if light energy is believed to be particulate this week, but is it possible that photons or other forms of high frequenty energy could be used as a repuslive force? There's still quite a bit we don't understand about this stuff, and though at this point it's still probably the rhelm of science fiction, It's not impossible. Remember, there are no fictionless surfaces, no perfect vacuums, no perfect superconductors, only asymptoticly approaching approximations.

      -Chris

      PS - I apologize in advance for the above average number of typos and possible flaws in knowledge and logic....I'm on an iMac today ;-)

      --
      --an unbreakable toy is useful for breaking other toys--
  11. Re:Ooh, IONs by WTFmonkey · · Score: 4, Informative
    Kind of an asshole, aren't you?

    I think what confuses some people is that we're used to pushing against something to go somewhere. People have a misguided idea that it's the exhaust pushing against the ground that makes a rocket go, but it's actually the rocket pushing against its exhaust that makes it go. Basically, you mix two things together in a chamber, and under high pessure you shoot ("throw" in the parent's words) the resulting gases out the back end, and away you go. There's no need to interact with the atmosphere which is why rockets work in space and propellers don't.

  12. Re:ion engine limitations by Shihar · · Score: 3, Informative

    While the Ion engine is very slow, it actually turns out to be faster then most engines in the long run. For a normal engine they generally burn real quickly then the object just coasts to wherever it is going. With an ion engine they can burn for very long periods of time. Over long distances it is better to burn for a long time with a slow acceleration then it is to burn quickly.

    Even better, if you are doing something like flying to Mars, an ion engine combined with a normal engine has a lot of potential. Just strap a big old disposable solid fuel engine onto your spacecraft and let it burn dry. This will get you well on your way to your destination. Dump the solid fuel engine and continue to burn with the ion engine. You will get to where you are going fairly quickly.

  13. We Like The Moon... by Anonymous Coward · · Score: 3, Insightful

    We like the moon
    Coz it is close to us
    We like the moon
    But not as much as a spoon
    Cos that's more use for eating soup
    And a fork isn't very useful for that
    Unless it has got many vegetables
    And then you might be better off with a chopstick

    Unlike the moon
    It is up in the sky
    It's up there very high
    But not as high as maybe
    Dirigibles or zeppelins or light bulbs
    And maybe clouds
    And puffins also I think maybe they go quite high too
    Maybe not as high as the moon
    Coz the moon is very high

    We like the moon
    The moon is very useful everyone
    Everybody like the moon
    Because it light up the sky at night
    And it lovely
    And it makes the tide go
    And we like it

    But not as much as cheese
    We really like cheese we like zeppelins
    We really like them and we like kelp and we like moose
    and we like deer and we like marmots
    and we like all the fluffy animals
    We really like the moon

  14. Re:Ooh, IONs by FrostedWheat · · Score: 3, Funny

    For ever action their is an equal and opposite reaction

    I'm sorry, but that dosen't explain the curry from my local Chinese restaurant. The reaction is way bigger than the action. Perhaps they should have powered SMART-1 using that.

  15. Re:Its about time. by troc · · Score: 3, Insightful

    Yeah, That dammed Ariane 4 rocket was only the most successful, accurate, reliable launcher ever.

    Nasty horrid Europeans.

    Sure Ariane 5 has had some teething troubles but don't mock the Europeans, they are the ones who made space commercial. Ariane is much more reliable than the Delta or Atlas Centaur launchers the US uses and whilst the shuttle is quite reliable, it's a ridiculously expensive way to put a commercial satellite in space.

    --
    Troc's dubious podcast and blog: http://www.trocnet.net
  16. Re:Its about time. by jdhutchins · · Score: 4, Interesting

    You're russian history is incorrect. They have had several mishaps. The ones that I can think of off the top of my head are Soyuz 1 and Soyuz 11. They have probably had somewhere between 150-200 manned launches. We'll hav change your definition of "launch mishap" to "the rocket went up but the people didn't come down alive".
    We have had two accidents in our space program (3 if you count Apollo I, but in the above definition, it doesn't count)
    The Russians do more launches than we do. In the past, they've done more manned launches than we did. Since the past 5 years, I'd say that we've probably done about the same number of manned launches.

  17. Other science fiction reference... by dpilot · · Score: 4, Interesting

    This one is more reputable, I believe credited to Arthur C. Clarke.

    It was a short story about an Earth-to-Moon (orbit-to-orbit) space race, in the spirit of the Kremer prize. The spacecraft were propelled by ion engines, which were energized by Whimshurst-type machines, which were powered by ...

    bicycles.

    The racers pedaled their way to the moon, the pedals effectively powering the ion engines that drove them. The race took several days, with the right stuff added in for absurd athletics, rest breaks, minimal life-support, race security, etc.

    No doubt someone here will do the math that I never bothered trying to do. One of these days, maybe I will.

    --
    The living have better things to do than to continue hating the dead.
  18. Re:Ion drive is cool, but... by adeyadey · · Score: 4, Informative

    This is really a test bed for the ion-drive technology - although even on this mission, its effective to do it this way, once in lunar orbit the drive can make slow adjustments to cover the whole surface, without having to carry huge amounts of propellant. Over LONG periods of operation, the ion drive is something like 10 times more effective in terms of fuel carried vs thrust given compared to chemical rockets - and that figure is set to improve as research progresses. SMART-1 is an important step in that research. The Ariane-5 launch rocket is a fraction of the size/cost of the Apollo/Saturn-5's..

    In the future missions you will see these sorts of drives giving much faster flight times to Mercury, Mars, Jupiter, Saturn.. - although for the outer system you may need nuclear instead of solar power.

    Yes both this and parent are dupes from previous thread..

    --
    "You lied to me! There is a Swansea!"
  19. Ion Propulsion by Listen+Up · · Score: 4, Informative

    I spent a lot of time studying this technology while I was working towards my Bachelor's Degree. Okay, let's get some facts straight, for those of you without a degree in Mathematics or Physics:

    1) Ion Propulsion is NOT new technology. The Russians and German's have been experimenting with Ion Propulsion since the early 1950's. NASA is actually a late comer to the game, although the first with a completed ion propulsion engine.

    2) Ion Propulsion do not work in an environment with an atmosphere. An ion engine does not have enough force to lift a sheet of paper more than a few inches.

    3) An Ion Engine is very simple in design. For a simple explanation, an inert gas is ionized and injected into a chamber with an opening on one end. The opening has a magnetized torid ring around it. Using the right hand rule (make a fist, stick your thumb out like you are hitchhiking...your thumb is the direction of the electric current, your fingers are curled in the direction of magnetic field flow) you create an electrical flow around the metal torid ring. The resulting magnetic field 'pulls' the ions through the ring, resulting in propulsion.

    4) The reason for slow inital acceleration is because the force of the ions passing through the ring is very small, but the velocity of the ions is very high. So, since there is no friction or other losses in space, after a period of time the velocity of the ions leaving the ring increases the velocity of the engine. After a matter of days the engine can be travelling at 10-30,000MPH.

    For more information and history on Ion Propulsion engines you can go to the following websites:

    http://science.nasa.gov/newhome/headlines/prop06 ap r99_2.htm

    http://www.grc.nasa.gov/WWW/PAO/ds1.htm

    http://space-power.grc.nasa.gov/ppo/projects/nst ar /

    1. Re:Ion Propulsion by jd · · Score: 4, Informative
      Two small notes:


      First, this probe was from the European Space Agency, not NASA. NASA doesn't own Europe, as far as I know, and can't even afford to replace the bearings on the ancient platforms that carry the Space Shuttles to the launch pad.


      Second, NASA's Ion engine (on Deep Space 1) failed in lab tests, and then failed in space. NASA had to "shake" the probe using the gas-based manoevering jets, using up valuable fuel. The probe was a success in the end, but more by luck than design.

      --
      It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
    2. Re:Ion Propulsion by brocheck · · Score: 4, Funny

      Where-ever it is you live I imagine our glorious country is not far from demonstrating quite plainly where it is we've spent the money that was once sent to NASA for the foolish exploration of space (we already discovered there is no oil there). We may not have space-craft built in the last twenty years but what we do have speaks for itself: GPS guided smart-bombs, and a lot of them!

      Don't worry, citizen, soon we'll liberate you too!

      --

      suddenly I feel very tired

    3. Re:Ion Propulsion by Manhigh · · Score: 3, Informative

      The opening has a magnetized torid ring around it. Using the right hand rule (make a fist, stick your thumb out like you are hitchhiking...your thumb is the direction of the electric current, your fingers are curled in the direction of magnetic field flow) you create an electrical flow around the metal torid ring. The resulting magnetic field 'pulls' the ions through the ring, resulting in propulsion.

      Actually, what you describe there sounds like a Hall effect thruster. Not all ion drives are Hall thrusters.

      DS1's ion engine used charged grids rather than a metal toroid to achieve the acceleration of the ions.

      In addition to Hall effect thrusters and grid-based ion engines, there are also arcjets, resistojets, and the ever-sexy-but-a-few-years-off magneto-plasma-dynamic thrusters.

      --
      "Open the pod by doors, Hal" > "I'm afraid I can't do that, Dave" sudo "Open the pod bay doors, Hal" > alright
  20. Re:Ion drive is cool, but... by jd142 · · Score: 4, Funny

    The moon will still be there in 15 months.

    That's what you think. Ooops, I've said too much already.

  21. Re:Ion drive is cool, but... by Clueless+Moron · · Score: 5, Insightful
    slightly more economical???

    This project cost just 100E6 Euros. That's about one quarter the cost of a single shuttle launch, never mind the astronomical costs of each Apollo mission.

    Personally I'd much rather see 4 new projects like this and one fewer shuttle launch.

  22. Re:me? by geekoid · · Score: 4, Funny

    "Dark Sith" should that be moderated redundent? Or are there happy-go-lucky-smiley-face-Siths I'm unaware of?

    heh.

    --
    The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
  23. Xenon sucks by Waffle+Iron · · Score: 5, Funny
    It also talks about the low-cost technology being used and the charged xenon (ion) propulsion system.

    I hate those self-important A-holes who have those xenon propulsion systems. It seems like every night that I go for a short trip in low earth orbit, at least one schmuck has to fly by with those damned things turned on. How am I supposed to see where I'm going when I'm being blinded by the obnoxious blue glare that they spew? If they're the only ones who can see anything, it's not making things any safer overall.

    I swear, I'm going to start flashing these jokers with my laser range finder if they don't get more considerate and stop using those damned xenon units in congested orbits.

  24. thoughts by itzdandy · · Score: 3, Interesting

    if your '71 chevy truck is slow, you just put in a bigger engine right?! so how about a bigger ION drive. and a small nucleur reactor.

    i suppose you do lose some efficiency by carrying your own fuel, but nuclear power is far more efficient than solar power right now.

    with larger ION drives, or more small ION drives, and enough power from the reactor, this may be able to compete with a rocket engine for inter-solarsystem travel.

    but then again, id rather have laser,mazer, or phaser cannons. I'll travel really really slowly if I have a really big gun!

    --

    another advantage would be less vibration during accelleration. Imageing sending a team to Alpha Centauri using standard rockets. They would have to burn for 3 solid months to accellerate and the same to decellerate. 3 months is a long time to be strapped to a chair.

    this solves the lack of gravity problem as well. Just accellerate at a rate the would be near 1G or at some acceptable level of force, then spin the ship around and do the same thing for decelleration. This way you would have artificial gravity for a good portion of the trip. I can't imagine the side effects of a couple of years is zero G, and what happens when the team trys to go to the plannet with no muscles built up for planetside life.

    Alpha Centauri is something like 5,644,944,000 kilometers away, this is most likely a 5-10 year trip. Yes, artificial gravity would be good.

    Also, the waste material from the reactor could be used as the actualy propellant(maybee, IANORS(I am Not a Rocket Scientist) and then you wouldn't have to store it, you could just eject it out the back of the craft.

    1. Re:thoughts by ninthwave · · Score: 4, Informative

      ok Alpha Centauri is a star system consists of Alpha Centauri A, Alpha Centauri B and Proxima Centauri, that appears as a single star to the naked eye. Of that system we are closest to Proxima Centauri not Alpha Centauri. The distance to Proxima Centauri is 4.36 light years.
      In Kilometers this is:
      41,220,846,106,794

      So you calculation is a bit off in the time scale.
      To reach it in 10 years you would have to be going roughly half the speed of light or 150,000,000 meters per second

      --
      I was thinking of the immortal words of Socrates, who said: "I drank what?" - Chris Knight (Val Kilmer)- Real Genius
  25. Re:Ooh, IONs by f97tosc · · Score: 4, Informative

    Rockets use the same priciple that ion propulsion uses, the law of action and reaction (one of Newton's Laws, can't remember which one off the top of my head). Basically matter is accellerated out the back of the engine (by chemical means in the chemical rocket engine, and by using electro-magnetic forces in the ion propulsion engine). This accelleration causes causes a force to be placed on the engine that is equal to, but oppisite in direction, to the force accellerating the matter.

    All means of propulsion -on Earth and in Space- use Newton's third law.

    In practical terms, the difference is that Ion engines use energy from the sun, to accellerate small portions of matter (ions) over a long period of time.

    Rockets use chemical energy to throw out matter, typically violently for a short period of time.

    For these reasons Ion engines are predicted a bright future for travel over long distances (to the moon is unusually short in this context), there efficient use of energy wins out in the long run.

    However, it seems unlikely that they could be used for lifting things into orbit; then you need to quickly accelerate to high speeds and get out of the athmosphere. Ion Engines are probably not suitable for chasing X-Wings around the Death Star either for that matter.

    Tor

  26. Re:Its about time. by RayBender · · Score: 4, Interesting
    You're russian history is incorrect. They have had several mishaps.

    In more than 35 years of spaceflight the Russians have had something like 4 fatalities, and 3 (?) accidents (including one where the crew survived a booster failure in mid-flight - the stage didn't separate). In comparison to the U.S. record this is remarkably good. They have also flown more people for longer periods of time.

    Since the past 5 years, I'd say that we've probably done about the same number of manned launches.

    The same number of launches as the U.S., with a total budget of something like 200 million dollars, a factor of 30 less money. That's pretty impressive. The simple turth is that the U.S. is a second-rate space power.

    --
    Human genome = 3 billion base pairs = 6 GBit. Windows + Office = 20 Gbit. Which is more impressive?
  27. Re:Its about time. by gbjbaanb · · Score: 3, Insightful

    so what you're saying is that NASA is the Microsoft of the space industry, and Russia, Linux...

  28. Re:Its about time. by RayBender · · Score: 3, Interesting
    hey were also the first at everything in the space race apart from the manned moon landing... and if you believe that happened you'll believe anything. Seriously, is anyone still fooled by those dodgy special effects and the lame script writing?

    Yes, I damned well belive the Moon landings happened. I've done chemical analysis on the rocks; I've met some of the astronauts; my best friends dad helped build the LEM at Grumman. So yeah, they happened.

    I'm not sure what annoys me more: idiots like you who don't think it ever happened, or the idiots in the White House, Congress and the public who didn't think it's important enough to keep funding.

    I guess we're living in a society where our greatest achievements lie behind us, rather than ahead of us. In that situation I shouldn't be surprised that there are fools like you who try to make themselves feel better by claiming the achievements of the past never happened.

    --
    Human genome = 3 billion base pairs = 6 GBit. Windows + Office = 20 Gbit. Which is more impressive?