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New Nuclear-powered Spaceship Design Revealed

Iddo Genuth writes "A U.S. based company introduced an innovative propulsion system that could significantly shorten round trips from Earth to Mars (from two years to only six months) and enable future spaceships to reach Jupiter after one year of space traveling. The system, which may dramatically affect interplanetary space travel is called the Miniature Magnetic Orion (Mini-Mag Orion for short), and is an optimization of the 1958 Orion interplanetary propulsion concept."

72 of 285 comments (clear)

  1. Didn't we by scoot80 · · Score: 5, Funny

    recently have an article about trip to mars in a week? So.. this is really.. an inferior mode of transport for all those Mars holidayers...

    1. Re:Didn't we by blahdeblah2000 · · Score: 2, Informative

      Yep

      http://dialog.newsedge.com/newsedge.asp?site=2006121916143901110346&block=folderstory&briefs=off&action=XMLStoryResult&smd=true&storyid=p0906509.2rw&rtcrdata=off

      Also same site was touting anti-matter proplusion last year http://www.tfot.info/articles/33/new-antimatter-engine-design.html

      Also - do we really want to do fission - its so 20th century and dangerous - news today - The UK has built up a stockpile of 100 tonnes of plutonium - enough to make 17,000 nuclear bombs http://news.bbc.co.uk/1/hi/sci/tech/7006056.stm

  2. hopefully by weirdcrashingnoises · · Score: 3, Funny

    Hopefully this spaceship will be able to slow down before it reaches mars.

    Unlike some spaceships... http://science.slashdot.org/article.pl?sid=07/09/13/2328233

    --
    sigs... don't talk to me about sigs....
    1. Re:hopefully by moderatorrater · · Score: 2, Insightful

      What makes you think the photonic drive wouldn't be able to slow down? Does the drive not work if you flip the ship in the opposite direction?

    2. Re:hopefully by Propaganda13 · · Score: 4, Funny

      1) Start your trip from Earth Orbit, by firing up them engines and transferring into a nice trajectory to our friendly-neighborhood planet Mars.
      2) ???
      3) Profit!... no, I mean, half-way through the journey (or actually, just a little bit before half way, to give some leeway for properly transferring into a Mars orbital path), switch off them engines!
      4) Swing your craft around so that the pointy-end is towards the trajectory's rear and the business end (the engines) are pointing towards the trajectory's forward path.
      5) Fire up them engines again! Hey presto! You're now flying into nuclear explosions!
      6) ???


      fixed
    3. Re:hopefully by icebrain · · Score: 3, Informative

      It would work just fine... that is, assuming it works at all. The photon drive has a little problem; namely, it requires about 300 megawatts of power to produce a Newton of thrust... and that's at 100% efficiency.

      The Orion concept is much more technically feasable, barring any massive breakthroughs in materials and fusion power.

      --
      The meek may inherit the earth, but the strong shall take the stars.
    4. Re:hopefully by Minwee · · Score: 4, Funny

      6) Go back to school. Go directly to school. Do not pass Go, do not collect $200.
      7) Learn about strange new concepts like Galilean Relativity, Newton's Laws of Motion and Inertial Frames of Reference.
      7a) And no, I'm not going to link you to Wikipedia's articles on those. You're going to have to go with step six for that.
      8) Now that you understand why step five is no different from step one, you can figure out what step six was supposed to be.
      9) For extra credit, write "I will not talk out of my ass about Physics" 6x10^24 times on the chalkboard.

  3. Re:That's nothing.. by cduffy · · Score: 3, Insightful

    That's unfair. Gibson's "design" was loose speculation, whereas hard math has been done both on the original Orion and on this potential improvement.

    Certainly, neither of them has existed in practice -- but one was wild speculation, whereas the other had (and has) actual engineering.

  4. What about the surging nature of the propuslion? by Kaenneth · · Score: 4, Funny

    An WHUMP Orion WHUMP based WHUMP drive WHUMP can WHUMP be a WHUMP bit WHUMP rough, WHUMP any WHUMP study WHUMP on the WHUMP effects WHUMP on cargo/passWHUMPengers?

  5. What about manned? by Tanman · · Score: 2, Interesting

    speeding up via riding the wave of successive explosions is great for an unmanned craft. For a manned craft, though, I have a couple questions:

    1. How will people deal with the psychological effect of the never-ending pounding brought by this type of propulsion?

    2. Will scientists avoid this issue by instead strapping people into some kind of suspension and using a fewer number of larger explosions to get up-to-speed per day?

    3. What effect would that have on a person physically? We know people can take X G's, but what about being subjected to constant hits like that. If they are stronger, it could have some as-yet unforseen effect on our physiology.

    1. Re:What about manned? by flyingfsck · · Score: 4, Insightful

      How do deal with all those explosions in your car engine?

      --
      Excuse me, but please get off my Pennisetum Clandestinum, eh!
    2. Re:What about manned? by Fox_1 · · Score: 3, Informative
      1. lot of explosions in a car engine, and we're all mostly still sane. Seriously though they are small contained explosions (couple grams of material) that vent plasma, there is no reason why people in the passenger compartment would even be aware of each individual explosion. The point is that these are nuclear weapon sized explosions, but many smaller ones providing relatively constant thrust. It won't be jerky.

      2. I don't know if you understand how acceleration works. But Fewer larger explosions would make for a rougher ride. And you don't get up to speed on a day to day basis, that would be a weird way to fly a space craft.

      3. 1 g constant acceleration for a few hours is pretty freaking fast. This engine could do the thrust of the space shuttle - which is more then 1 g, but why would you do 12 g for more then a few minutes?
      If you do 1g acceleration for a full day you are going about After 1 day, you are going 800,000 m/s - 800km/sec or 288,000 km/hour mars is about 78million km away - so you can see how this is going, if you stop accelerating at this speed it's about a 4 or 5 million km a day just coasting, or 20 or so days to get there. So it's silly to do more then 1g acceleration, unless you are leaving a planets surface and need to reach escape velocity. So no worries about weird physical effects from the acceleration - now long term zero g is a whole'nother type of problem, but again no need to make it a long trip with this kind of power.

      --
      The rock, the vulture, and the chain
    3. Re:What about manned? by sssssss27 · · Score: 3, Insightful

      What's the difference? An internal combustion engine is coupled directly from the explosion all the way to the road, well at least in a manual car. The reason you don't feel each explosion though is that instead of using one big one there are thousands of tiny ones so it seems like a smooth motion.

    4. Re:What about manned? by Tablizer · · Score: 4, Funny

      1. How will people deal with the psychological effect of the never-ending pounding brought by this type of propulsion?

      Explains...why...Kirk...talked...like...this. The...future...is...here.

    5. Re:What about manned? by DigiShaman · · Score: 2, Informative

      A four, six, and eight cylinder engine will have their pistons out of phase from each other as to provide a continuous and smooth power curve. Now compare that with a single piston engine (lawn mower, weed eater...etc) and take notice of the excessive vibration. Even though the crank shaft has counter weights, it's the interleaving of the detonations (and flywheel) that provides smooth motion.

      --
      Life is not for the lazy.
    6. Re:What about manned? by Duhavid · · Score: 3, Informative

      There is also the flywheel, which dampens the effect of each combustion event.

      Also, it is not an explosion, but rapid combustion.

      Further, the magnitude of the events is quite different
      ( in a car engine, the events are relatively small,
          on orion, well, bigger ).

      --
      emt 377 emt 4
    7. Re:What about manned? by Grond · · Score: 4, Informative

      The full press release notes that the maximum acceleration would be a mere .6 G's or so, which is more than Mars but obviously less than Earth. This is unlikely to result in any unknown physiological changes. In fact, the at least occasional exposure to g-forces would probably be beneficial compared to continuous micro-gravity.

      Anyway, a 100 metric ton craft would be pretty wimpy. That's 5% of the Space Shuttle's mass, for instance. I suspect this would be an unmanned mission. (For reference, the Apollo Service Module & Lunar Module together were about 40 metric tons and the longest Apollo missions only lasted 12 days).

      Also, the 'ignition mass' for the fastest version would be a whopping 1300 metric tons of plutonium. Using uranium prices as a stand-in, that's about $300 million in fuel. That's an awful big price tag for just getting a larger probe to Mars faster.

    8. Re:What about manned? by fyoder · · Score: 3, Funny

      I think many of your concerns would be addressed by the addition of an inertial compensator. As the wikipedia article points out, this may not fully protect against sudden shocks. It also seems less effective on people suffering from HPD (hamminess personality disorder), who may be thrown about much more violently than people less drama prone.

      --
      Loose lips lose spit.
    9. Re:What about manned? by modecx · · Score: 5, Interesting

      Isn't it kinda sad that people on a site which is supposedly for nerds can't naturally grasp the idea of waves, pulse-width, modulation, duty cycle, and psychophysical thresholds?

      Exactly what kind of nerds are they cranking out these days?

      --
      Constitutional rights may be respected, repealed, or modified; but they must never be ignored.
    10. Re:What about manned? by zippthorne · · Score: 2, Informative

      "Dampen" doesn't mean what you think it means. Or rather, it wouldn't if people would stop adding superfluous letters to seem more intelligent.

      The word is damp. The infinitive is "to damp" and a device which damps is a damper. There's no need for the extra -en unless you want to have a confusing half-synonym for moisten.

      On an orion, the pusher plate is connected to the main spacecraft body by shock absorbers. Quite similar to a gun recoil mechanism, I imagine, except that for manned flight it would spread the impulse out over a much longer time period. Timed just right, occupants of a habitat at the top of the structure would experience constant acceleration.

      The main problem with Orion is that it doesn't solve a problem that exists. It has less Isp than some of the better electric propulsion options, and huge structure requirements. It is high thrust, high Isp, so it's main use would be getting off the planet, but its nature contraindicates ever being used within the atmosphere.

      --
      Can you be Even More Awesome?!
    11. Re:What about manned? by PitaBred · · Score: 5, Funny

      It's now more popular to be a nerd, rather than just a state of being for people who are truly drawn to it, so you start getting a lot of wannabe's who can't hack it intellectually, but are still drawn to the "lifestyle", or more the perks of being known as a nerd. For example, look at Apple users ;)

    12. Re:What about manned? by gravij · · Score: 4, Informative

      "Dampen" doesn't mean what you think it means. Or rather, it wouldn't if people would stop adding superfluous letters to seem more intelligent.

      The word is damp. The infinitive is "to damp" and a device which damps is a damper. There's no need for the extra -en unless you want to have a confusing half-synonym for moisten.
        Care to back that up? No source that I could find online supported your claim. All I found was this:
      (from dict.die.net)
      Source: Webster's Revised Unabridged Dictionary (1913)

      Damp \Damp\, v. i. [imp. & p. p. Damped; p. pr. & vb. n.
            Damping.] [OE. dampen to choke, suffocate. See Damp, n.]

            2. To put out, as fire; to depress or deject; to deaden; to
                  cloud; to check or restrain, as action or vigor; to make
                  dull; to weaken; to discourage.

      Source: Webster's Revised Unabridged Dictionary (1913)

      Dampen \Damp"en\, v. t. [imp. & p. p. Dampened; p. pr. & vb.
            n. Dampening.]

            2. To depress; to check; to make dull; to lessen.

      Dampen \Damp"en\, v. i.
            To become damp; to deaden.
    13. Re:What about manned? by NeMon'ess · · Score: 2, Funny

      If he owns a DeLorean he's my new best friend.

  6. Oh dear... by Roger+W+Moore · · Score: 4, Funny

    ...I think someone forgot to tell the sun.

  7. Re:jupiter? by Anonymous Coward · · Score: 2, Interesting

    Like all things to do with space travel, it depends on how much you're willing to pay

  8. Like stepping on the gas to get to Wyoming... by patio11 · · Score: 2, Funny

    ... this just means you get to nowhere faster.

    (Sorry, reflexive poke at Wyoming. Wyoming has wonderful people, natural resources, and breathable atmosphere. Mars is 0 for 3. Jupiter doesn't even have a surface to land on, but now we can hurry up to get there and not land on it! Like the robot we're sending had some place it would rather be for the marginal time...)

    1. Re:Like stepping on the gas to get to Wyoming... by thatskinnyguy · · Score: 2, Informative

      Ummm Jupiter may have a surface to land on.

      --
      The game.
  9. Re:Nice idea but... by hedwards · · Score: 3, Insightful

    A treaty is only as good as the signatories. There is no particular reason why the signatories couldn't write and sign a new treaty that just specified that there were to be no nuclear powered satellites in orbit or nuclear weapons in space.

    As that is more or less the intent. A spaceship that was nuclear powered would really only be an issue if it was allowed to orbit the earth long enough to fall out of orbit.

  10. Pics by StikyPad · · Score: 4, Funny

    Here's a few pics of the Mini-Mag in action. Looks vaguely familiar... Interesting how the cargo capsule seems to release from one end and dock at the other. Very intriguing.

  11. Wrong by StefanJ · · Score: 2, Informative

    Nuclear weapons, yes.

    Power sources, no.

    There are plenty of probes and spy satellites that are powered by plutonium-laden RTGs.

    1. Re:Wrong by Nyeerrmm · · Score: 2, Insightful

      Orion operates by exploding a weapon against a thrust plate, so it really qualifies as a weapon, which is at least one reason Orion was cancelled. I'm not sure how the treaty applies to space-based reactors, but theres definitely a large difference between an RTG and reactor as well.

    2. Re:Wrong by zippthorne · · Score: 3, Interesting

      Which is quite ironic, considering Orion was conceived as a way to reduce nuclear weapons stockpiles...

      --
      Can you be Even More Awesome?!
    3. Re:Wrong by TheRaven64 · · Score: 3, Insightful

      A hammer can be either a weapon or a tool. And, while I'd object to a ban on hammers in general, I wouldn't object to a ban on people swinging hammers within a foot of my face. Scale this up by a few orders of magnitude, and you've got nuclear arms limitation treaties.
      --
      I am TheRaven on Soylent News
    4. Re:Wrong by tgd · · Score: 2, Informative

      No it wasn't.

      Not even close.

      Go read some books about who was involved with the Orion designs, when those plans were put together and when the "reduce stockpiles" movement started -- you'll see how ridiculous a statement that is.

  12. Bulk??? by Goonie · · Score: 2, Interesting

    If their gadget for doing the z-pinch thingy is anything like the Z machine at Sandia you won't be putting it on a spacecraft any time soon...

    --

    Any sufficiently advanced technology is indistinguishable from a rigged demo
    --Andy Finkel (J. Klass?)
  13. Re:Nice idea but... by Jarik+C-Bol · · Score: 2, Informative

    no, nuclear weapons in space are banned by treaty. we use nuclear power in the form of nuclear batterys in space all the time. mostly because they can stand up to the temprature extremes of space, and will outlast the hardware they are installed in. (Vs a alkaline or some other form of battery, which does not have these properties.)

    --
    I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
  14. The best part of the mini-mag design by Anonymous Coward · · Score: 5, Funny

    If you unscrew the cap in the stern of the spacecraft, you will find a spare nuclear reactor behind the battery terminal.

  15. Reduces travel time how? by Cousarr · · Score: 5, Interesting

    First off, I am not a rocket scientist, but I am studying for a BS in Aerospace Engineering.

    How exactly is this supposed to reduce travel time? Current lengths of travel are not due to a lack of available thrust or due to amount of fuel available but rather the path taken to reach the destination. Currently in order to travel to say Mars Hohman transfers are often used. These paths and others like them take a certain amount of time to complete, and stronger engines or more available Delta-V allow only for more instantaneous entrances of the transfers or more allowed change in course once at the ship's destination.

    In order to reduce time traveled a different orbital mechanic is needed. Even if a ship were to travel in a straight line toward a destination at a rapid enough speed that it would not have to meet up with it too much further along in its orbit it would have to be able to kill relative speed quickly enough to enter a capture orbit.

    Anyone know what orbital transfer method they're saying that this engine makes possible?

    1. Re:Reduces travel time how? by StefanJ · · Score: 5, Interesting

      As I recall, Hohman orbits are nice ellipses with body A at perisol and body B and aposol. You make a burn to get into it and out of it; the delta-v required is the difference in velocity between a body in a "circular" orbit at that radius and the velocity of a body in the elliptical orbit. If the planet happens to be at that point, you then just need to make another burn to get into orbit. Timing is important.

      Even Hohman orbits are too "spendy" for chemically fueled rockets. Thus the complex back-and-forth gravity-assist paths that NASA probes take on the way to the outer planets, and the use of aerobreaking by Mars probes.

      Other, faster transfers are possible. You just enter another sort of elliptical orbit whose path intersects earth's orbit when you leave it, and the destination planet's orbit at a time when the planet will be there. Of course, you have to have a spaceship capable of the much greater change in velocity to enter these orbits.

      The linked-too documents suggest that the "mini mag" is not only fuel efficient (read: high Isp), but has a decent amount of thrust. This means it CAN make the drastic changes in velocity necessary.

    2. Re:Reduces travel time how? by Nefarious+Wheel · · Score: 3, Interesting
      My guess is that it turns around about half way during the trip to start slowing down.

      Wouldn't necessarily be half way, we're not talking linear vectors are we? If we're playing catch-up with a planetary target the crossover point might be a bit later than km/2. It's more expensive to escape the closer you are to the sun's gravity well, but I'd think a lot of the energy would be soaked relative to the velocity of the target, i.e. there may not be as much energy to dump near the target. Space ain't flat, found that out from my office mate who was doing the orbital geometry for Pioneer Venus 12/13 some years back (which had the inverse effect, being inward from EO).

      I don't know why he kept a separate set of comps in furlongs per fortnight, but us programmerz was wierd back then.

      --
      Do not mock my vision of impractical footwear
    3. Re:Reduces travel time how? by king-manic · · Score: 2, Informative

      Hohman transfers are slow and cheap; that's why we use them. If you have a much more energy-dense fuel supply (plutonium certainly fills the bill) there are much faster routes available.

      I prefer a holtzman Transfer. Get there in 0.01s. Only bad thing is no one knows how it works except god and Holtzmans wife. And God help you if you bring a laser pointer.

      --
      "There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy."
    4. Re:Reduces travel time how? by DerekLyons · · Score: 2, Insightful

      First off, I am not a rocket scientist, but I am studying for a BS in Aerospace Engineering.

      At what level? A sophmore in high school? (Translated: I love how people wave about unrelated credentials as if it gives weight to what they are talking about.)
       
       

      How exactly is this supposed to reduce travel time? Current lengths of travel are not due to a lack of available thrust or due to amount of fuel available but rather the path taken to reach the destination.

      Half true at best - because the current travel lengths are a product of the low amounts of Delta-V available. (And acceleration is itself a product of fuel and thrust.)
       
       

      Currently in order to travel to say Mars Hohman transfers are often used.

      Duh! Because they are low energy orbits.
       
       

      These paths and others like them take a certain amount of time to complete, and stronger engines or more available Delta-V allow only for more instantaneous entrances of the transfers or more allowed change in course once at the ship's destination.
      Another half truth - what you say is only true below a certain level of Delta-V. Once you get above that level, you simply proceed to your destination by a more direct path.
       
       

      In order to reduce time traveled a different orbital mechanic is needed. Even if a ship were to travel in a straight line toward a destination at a rapid enough speed that it would not have to meet up with it too much further along in its orbit it would have to be able to kill relative speed quickly enough to enter a capture orbit.

      Duh. Anyone who read Heinlein as a ten year old knows this.
    5. Re:Reduces travel time how? by Nyrath+the+nearly+wi · · Score: 2, Informative

      Hohmann transfers are used because feeble chemical propulsion cannot produce the delta V required for a quicker transfer orbit.

      Atomic Rockets

      At the other end of the spectrum of transfer orbits are Brachistochrone trajectories. When the propulsion system becomes powerful enough to produce delta Vs higher than about 10 km/sec, you can treat the planets as being essentially stationary, that is, they will not move appreciably in the short time required for transit.

  16. Re:What about the surging nature of the propuslion by Arabani · · Score: 4, Informative

    The original studies performed extensive studies on this problem. They solved it with a double shock absorber system; by tuning the absorbers and the frequency at which bombs were ejected, they could achieve a constant acceleration of 1-2 g.

  17. Not like old Orion by StefanJ · · Score: 2, Interesting

    This one is going to be built in orbit. It will never take off or land.

    OTOH, the "fuel" pellets are going to be made of fissionable materials. I hope they point the nozzle in a direction that doesn't result in un-detonated bomblets burning up in the atmosphere.

    1. Re:Not like old Orion by Ungrounded+Lightning · · Score: 4, Informative

      You do realize that burning coal has put more Uranium into the air than all the atomic explosions combined right?

      I'm more worried about Strontium 90 and radioactive iodine.

      Given that Hanford deliberately released a BUNCH of radioactive iodine upwind of an indian reservation at least partly to see what its effects would be on the "marginal population" of indians and rednecks downwind (leading to a considerable increase in birth defect constelations and graves' disease), I suspect others are with me on that.

      --
      Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  18. Slashdotted? by barakn · · Score: 2, Funny

    These people are visionaries, except when it comes to anticipating large server loads.

    --
    "I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
    1. Re:Slashdotted? by Tablizer · · Score: 2, Funny

      These people are visionaries, except when it comes to anticipating large server loads.

      Indeed. The ship will reach Jupiter before the damned bytes get to me from their server. Discrimination! Guess I'll go off my diet to compete with Jupiter.

  19. Jup in a Year by Tablizer · · Score: 4, Informative

    and enable future spaceships to reach Jupiter after one year of space traveling.

    The New Horizons probe, heading to Pluto, took slightly more than a year to reach Jupiter. However, there was no need to stop (park in orbit) and it didn't need to carry bulky life-support stuff. Thus, it could take the fast train.

  20. Cassini by mark0 · · Score: 4, Informative

    You mean like a plutonium powered vehicle?

    1. Re:Cassini by MillionthMonkey · · Score: 3, Informative

      An RTG doesn't count. If they use plutonium, it's Pu-238 (alpha emitter) with a half life of less than 90 years, not Pu-239 which has a 90,000 year half life (fewer watts per gram) and can support a chain reaction (so it's needed for other things). There are lots of them scattered about the former Soviet Union so if you're doing any hiking there, avoid heat-emanating ceramic objects.

      When not using solar panels (conspicuous and vulnerable) Americans like to power their satellites with RTGs. The Soviets put 35 reactor-powered satellites in orbit and only a few RTG-powered satellites. What was forbidden by the treaty was nuclear weapons, specifically including tests. An interstellar spacecraft powered by nuclear explosions would be a great way to sneakily test your weapons in full view of everyone.

  21. Transfer orbit by Kadin2048 · · Score: 5, Funny

    I believe they are using the "Journalist Transfer Orbit." This is a highly specialized piece of orbital mechanics: basically, you take the average distance to the destination as given by Wikipedia and divide by the spacecraft's top speed.

    --
    "Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
  22. Re:That's nothing.. by AKAImBatman · · Score: 4, Informative

    Reading the (now Slashdotted) article, it sounds like this design came directly out of research done into antimatter catalyzed micro-fission. ACMF is a well-proven technology that uses minuscule amounts of antimatter to kickstart or enhance a fission reaction. Because the technology was fairly straightforward and had good returns for antimatter quantities that are reasonable to produce, NASA was funding research into an engine called ICAN.

    I remember that there was some talk of actually launching a small probe based on the concept, but apparently the plan was scrapped. (Probably to help fund manned space travel.) Whatever antimatter confinement technologies they were working on may have led to the development of this new magnetic confinement fission technology. Or it could just be a coincidence.

    Either way, nuclear technology of this sort is fairly well developed and is not a pipe dream. At least not from an engineering standpoint. Getting the risk adverse US Government and NASA to actually build one of the many known-quantity engines we have on hand is a completely different ball of wax. They're still trying to get us reliable LEO access (Thank God for Griffin is all I can say), so I doubt we'll be seeing any advanced engines in practice until the CEV/Orion project enters its third phase.

  23. Re:jupiter? by moosesocks · · Score: 5, Funny
    Obligatory:

    Fry: Hey, as long as you don't make me smell Uranus. (laughs)
    Leela: I don't get it.
    Professor: I'm sorry, Fry, but astronomers renamed Uranus in 2620 to end that stupid joke once and for all.
    Fry: Oh. What's it called now?
    Professor: Urectum.
    --
    -- If you try to fail and succeed, which have you done? - Uli's moose
  24. Blog troll. Link to real info here. by Animats · · Score: 5, Informative

    First, this is a blog troll, to drive traffic to some ".info" site. The actual paper, "Proposed Follow-on Mini-Mag Orion Pulsed Propulsion Concept" presented at an AIAA conference last year, is more useful.

    The basic idea is to create a small fission (not fusion) explosion using magnetic compression. Nuclear weapons use chemical explosives to create an implosion, and during the implosion the fissionable material is compressed hard enough to get a 1.5x to (maybe) 2x density increase. With magnetic compression, a small pellet can be compressed hard enough to get a 10x density increase. This allows smaller explosions, around 50 gigajoules instead of the 20 terajoules of a fission bomb. They want to use curium or californium as the fuel, rather than plutonium.

    They also want to use magnetic containment, rather than an Orion-style "pusher plate" sprayed with oil. Unclear if that can be made to work.

    The experimental work (they compressed an aluminum cylinder with a big magnet at Sandia) was done back in 2002. This isn't really under active development.

    It's not a totally unreasonable idea, but it would be a huge job to make it work. For one thing, the plan is to assemble a large spacecraft in orbit, not to take off from Earth. It doesn't help with the problem of putting mass in orbit.

    1. Re:Blog troll. Link to real info here. by Ungrounded+Lightning · · Score: 4, Informative

      They also want to use magnetic containment, rather than an Orion-style "pusher plate" sprayed with oil. Unclear if that can be made to work.

      Ought to be a cake-walk once they've got the field in place to make it go "bang".

      The pellet is ALREADY confined in a mag field. The re-expanding plasma from the explosion dumps much of its energy into compressing the field between the plasma and the conductor that created it, making the field stronger (and dumping a bunch of the energy back into the conductor as electricity for potential reuse or consumption).

      Should be easy to create a selective leak in the desired direction and more fields to guide the plasma as it makes its getaway. (In fact the compressed field toward the vehicle can be used as a spring to return some of that collected energy to the plasma, further increasing the exhaust velocity. And/or the energy from the compressed field could be used to create or strengthen the "nozzle" guiding fields, just-in-time to guide the burst of plasma.)

      Lots of opportunity for cute electric/magnetic/plasma engineering tricks here.

      And unlike fusion the time scale, from ignition to completion of the exhaust cycle, is short, so plasma instabilities aren't an issue.

      --
      Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
    2. Re:Blog troll. Link to real info here. by DerekLyons · · Score: 2, Insightful

      It's not a totally unreasonable idea

      So long as you don't look too hard at the specs on the unobtanium reactors used to power the whole thing.
    3. Re:Blog troll. Link to real info here. by Cerebus · · Score: 2, Interesting

      My understanding is that one of the killers (no pun intended) of the Orion concept was that radioactive ejecta from the drive would inevitably find its way to ground-level, even if it was operating in Lunar orbit. It was mentioned in Dyson's book _Project Orion_ that they had estimated the number of annual excess deaths from cancer caused by launching a single Orion from ground as well as from various orbits.

      Since this concept will still eject various nasty radioisotopes as well, I wonder if they've done the same analysis.

      --
      -- Cerebus
    4. Re:Blog troll. Link to real info here. by careysub · · Score: 2, Informative

      The basic idea is to create a small fission (not fusion) explosion using magnetic compression. Nuclear weapons use chemical explosives to create an implosion, and during the implosion the fissionable material is compressed hard enough to get a 1.5x to (maybe) 2x density increase. With magnetic compression, a small pellet can be compressed hard enough to get a 10x density increase. This allows smaller explosions, around 50 gigajoules instead of the 20 terajoules of a fission bomb. They want to use curium or californium as the fuel, rather than plutonium.

      The experimental work (they compressed an aluminum cylinder with a big magnet at Sandia) was done back in 2002. This isn't really under active development... It's not a totally unreasonable idea, but it would be a huge job to make it work.

      Good post.

      To expand upon it a bit, I will observe that actual pressures and compressions demonstrated so far are maybe a couple of orders of magnitude below what is needed to achieve 10-fold compression of fissile material. They demonstrated pressures of 2.4 megabars (atmospheres) and roughly two-fold compression in aluminum, performance generally similar to what high explosive implosion systems have produced for over 50 years. Despite decades of work, HE implosion has never been scaled to the pressures or compressions postulated for this. See: APS and AIP pages on this.

      Now, their ace-on-the-hole is that they can achieve isentropic compression (i.e. optimal compression, without heating) explosive systems cannot, but even so they aren't in the ball-park with this, only looking at it with binoculars. And the Z-machine is a huge immobile installation. How to convert a grossly souped up version of it to practical flight-ready hardware would be a staggering task.

      So this is in the same league as commercial fusion power. A concept that has some grounding in reality, but possibly one forever beyond practicality, and certainly beyond the working career of any living engineer.

      --
      Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
  25. Re:Nice idea but... by GreggBz · · Score: 3, Informative

    The use of nuclear weapons is banned, yes.

    There has been research into nuclear rockets (NERVA), and nuclear power sources.

    Project Prometheus shows promise. Already, most of the long range probes that NASA has use radioactive decay as a power source, which is pretty safe and reliable.

  26. Re:That's nothing.. by Rei · · Score: 5, Informative

    Still, this has very little to do with Orion apart from them both being nuclear pulse propulsion. They only call it a successor to Orion because most people are familiar with Orion.

    Orion has already been obsoleted by a similar (but much more effective) design using normal-sized nuclear explosions -- Medusa. Medusa reverses the Orion design, having a parachute in front towing the craft, and detonating the explosives in front of the parachute. It uses structures in tension instead of compression (lighter), it allows the explosions to be further from the craft (less radiation), allows a longer acceleration stroke (smoother acceleration), and captures a larger percentage of the explosive energy.

    --
    Then the winter came, and the Grasshopper died. And the Octopus ate all his acorns. Also, he got a racecar.
  27. Andrews Space by sabre86 · · Score: 3, Informative

    The company behind the technology is Andrews Space at this site.

    From my (admitted limited) viewpoint as an (inexperienced) aerospace engineer, they look like the real thing.

    The system is actually described in a 2003 AIAA conference paper linked on this page. The paper is titled "Mini-MagOrion: A Pulsed Nuclear Rocket for Crewed Solar System Exploration."

    I've only glanced over the article so far, but it suggests specific impulses in the 10,000 seconds plus range. That's a critical measure of efficiency in a rocket that dictates the velocity it can obtain. The shuttle's SSMEs get about 455 seconds of specific impulse at a high thrust (millions of Newtons) and ion drives, like the one on the DS1 probe, and the like get specific impulses (Isp) of about 3000 seconds at low thrust. (millinewtons). Apparently the Mini-Mag Orion can produce thrust on par with the SSME. Yikes.

    --sabre86

  28. Reminds me of... by madbawa · · Score: 3, Funny

    ...Calculus!! I think it was Destination Moon or Explorers on the Moon (Adventures of Tintin). He had a nuclear powered rocket then. Bah!

  29. Wanted : Space Based Uranium Source by tjstork · · Score: 4, Interesting

    The common thread that we keep coming back to is that to really do spaceflight, you must have some form of nuclear power. The laws of physics are profoundly strong on this point. Space is too far and gravity is too strong for chemical rockets to really be successful.

    The ideal solution is to find a source of uranium in space, beyond Earth's gravity well, such that, we can mine the uranium in space, and fuel nuclear powered spacecraft from perhaps the moon. I don't see that happening any time soon, as, it is my understanding that its is practically a fluke that a relatively small body like Earth should wind up with such a heavy ore at all. The gods were kind to us during our solar system formation, and it feels unlikely that any asteroid should have a significant uranium deposit.

    That leaves us to launching live reactors into space from Earth. Unfortunately, despite safety precautions, the environmental movement makes the development of nuclear powered spacecraft a political impossibility. We can't even build a reactor on land without a mountain of red tape and lawsuits from the greens, even when we know that building such reactors are necessary to combat global warming. Putting a nuclear reactor into something that flies is unthinkable to them, and they would surely think that putting a nuclear reactor into a rocket is downright crazy. Even RTGs, relatively benign, are met with protest. Were it up them, there would be no pictures of Saturn at all from Cassini.

    In this one area, the left wing claim to scientific curiosity falls flat on its face. The science is not worth the risk. I think the key to be able to do this, really, is going to be to engage the right wing instead and paint such research as a matter of national security. The right wing, despite its proclaimed conservatism, has a penchant for throwing caution into the wind when it suits it. Heck, they'd blow off global warming just to be able to keep driving trucks. Put a nuclear reactor on a spacecraft to get to Mars in a few weeks, sure, why not? For them, though, the issue is going to be why. Doing it just for the science isn't going to cut it. However, the right does have a penchant for engaging in enormous projects for ideological goals - witness the cold war with Russia, the current war on terror and the invasion of Iraq. None of THOSE projects were cheap or short term, and honestly, only the right wing has the zeal needed to overcome failure after failure as would occur in a really long term space colonization project. Even if you disagree with it, religion is an enormously powerful motivator.

    Thus, you'll never get many righties to buy into space for the science, or the future profits, because both don't really do much. But if you could sell them space as a religious duty, then by God, they will say screw the left, throw a hundred billion dollars a year into building nuclear rockets that this country needs, all to create christian colonies on planets and take resources from asteroids. If anything, one could always further argue that with the Russians claiming the North Pole, then, the USA has to claim (something), and it may as well be Mars and the asteroid belt. Asking them to void the UN Treaty on claiming stuff on space would elicit an automatic yes - as the right is already predisposed against the UN.

    Surely such a project would be better for the world than the war on terror.

    The point is this, and this goes for both left and right. We are entering a time of great consequence for the United States, if not the world, and, it is time for us to stop seeing each other as enemies simply because we have different ideologies. We can make our differences work for us, so long as we express what we want for ourselves as individuals, not as collective party members, and from there identify those strengths we have in each other.

    In my case, I selfishly want to see the USA building a fleet of nuclear, manned, rockets, mining asteroids, and colonizing other planets. And, if I have to read the

    --
    This is my sig.
    1. Re:Wanted : Space Based Uranium Source by Nefarious+Wheel · · Score: 2, Insightful
      There's a whole planet spread out in pieces between Mars and Jupiter. Should be a few lumps of sub-critical mass in there you can mine.

      I kind of agree, kind of disagree with your assertion about the reasons why people would go into space. Right-wing? I don't think so, necessarily -- unless your definition of right wing means people who are most easily influenced. Your equation is cogent but your coefficients are wrong, I think.

      It isn't right-wing so much, I'd say rather that it's the category of people who are capable of being inspired by an inspirational leader. Kennedy wasn't right-wing, but he effected the space program as a reaction to the Soviet space successes (ok, the Soviet Union was slightly to the right of Atilla the Hun, despite their bolshie-leftie origins. You score a point on that one).

      The point is you need a critical mass who sense a need, and an inspirational and visionary leader as an ignition source in an environment of social awareness heightened enough to form a response. I'd put my money behind the one with the best rhetoric.

      Or how about this? Find a way to determine that the stone in the centre of Mecca is chemically identical to a rock in the Asteroid Belt, and you'll have millions of people with a new interest in recapturing the scientific advantage they had a few hundred years ago.

      Ok, I think I need to go home now and pop a couple of tinnies before my metaphors get any more mixed...

      --
      Do not mock my vision of impractical footwear
  30. Re:That's nothing.. by donaldm · · Score: 3, Insightful

    Even if this craft can reach speeds of 10% the speed of light we would still be limited to interplanetary exploration and exploitation (human nature dictates this). As far as interstellar travel goes it would still take about 45 years to send a spacecraft to the nearest star, not to mention the 4.5 year transmission delay. Still interplanetary travel is a big breakthrough if this article can be believed.

    The real breakthrough would be an interstellar spacecraft (the realm of Science Fiction at the moment) and this would really open up our galaxy, however a person would have to live for thousands of years to visit each solar system in our galaxy for just one day even assuming travel between each solar system is almost instantaneous. Think "Star gate technology. Well I did say in the realm of Science Fiction :-)

    --
    There ain't no such thing as proprietary standards only proprietary formats. Standards are by definition open.
  31. The solar system is big enough for the moment. by Ihlosi · · Score: 4, Interesting
    Even if this craft can reach speeds of 10% the speed of light we would still be limited to interplanetary exploration and exploitation (human nature dictates this).



    The solar system is a big enough place for exploitation, and when we're done with the planets and their moons we can look at the Kuiper belt. That should keep us busy for the next couple of centuries, at least, and also allow us to use technologies to actually analyze nearby star systems without having to send probes there just yet.


    And once the solar system gets too small for use, we probably have the necessary technologies, experience and infrastructure to send something on an interstellar voyage (probably a generation ship or even a small planetoid outfitted with propulsion systems).

    1. Re:The solar system is big enough for the moment. by shinma · · Score: 2, Interesting

      a small planetoid outfitted with propulsion systems We could call it Warworld.
      --
      Shinma
    2. Re:The solar system is big enough for the moment. by JWW · · Score: 2, Funny

      "a small planetoid outfitted with propulsion systems"

      Am I the only one who thinks we should paint this thing with flowers and peace symbols like a 1960's volkswagen camper van?


      Yeah, because the first thing that popped into my mind was a moon looking thing with a planet destroying laser ;-)

  32. Your Vision for Lewis and Clark? by WED+Fan · · Score: 3, Insightful

    The solar system is a big enough place for exploitation, and when we're done with the planets and their moons we can look at the Kuiper belt. That should keep us busy for the next couple of centuries...

    And the President said, "Lewis, Clark, I want you to walk around the block of the White House, its plenty big, and there's probably a lot for you to see. When you're done with that, check out Virginia. Once that is done, I want a complete survey of everything east of the Mississippi. That should keep us busy for a century."

    Lewis replied, "What about the vast unexplored reaches of the west?"

    To which the President slammed his fist into the desk, "Slow down, Sparky, that would take lots of money that would be better spent on the vast wasteland of New Jersey. And, it would take a long time and nothing good would come of it, I'm sure. And, it would take you forever to get the results back to us. And, you'd smell when you got back. Hell, Clark smells already. Now, you guys do as I told you, none of that 'Vast Vision' stuff."

    Knowing they were beat, Lewis and Clark resigned themselves to taking a walk around the block.

    "Besides," the President said, "When you finish up, you can both do commercials for Lost Horizon Airlines."

    Hey, why does exploration have to be serial?

    --
    Politics is the art of looking for trouble, finding it everywhere, diagnosing it incorrectly and applying the wrong fix.
  33. Not a Weapon by WED+Fan · · Score: 2

    Orion operates by exploding a weapon...

    Show me the weapon.

    A laser pointed at someone with the intent to cause harm - Weapon.

    A laser pointed out the backend of the space craft for propulsion - Engine.

    A rocket launched into a schoolyard from a neighboring territory - Weapon.

    A rocket strapped to a frame with wheels on a Utah salt flat - A really stupid but exhilorating way to die, and an Engine.

    So, Einstein, show me the goddamned weapon ! Too many of you freaks out there saying, "We shouldn't...", "But there's a treaty...", and some such nonsense. But you are all for saying things like, "Well its a bad law or treaty," when its something that you want.

    Show me the goddamned weapon!

    --
    Politics is the art of looking for trouble, finding it everywhere, diagnosing it incorrectly and applying the wrong fix.
  34. *Your* Vision for Lewis and Clark. by pavon · · Score: 2, Insightful

    And the President said, "Lewis, Clark, I want you to go explore the moon. The country needs inspiration and I am going to provide it for them"

    Lewis replied, "But, sir we have no way to get to the moon. Why don't we explore all that land out west that we just purchased. Few if any european has ever seen it. Meanwhile we can learn more about the moon with new telescopes, which will make us more prepared if we ever do go there."

    To which the president slammed his fist into the desk, "You have no vision! Besides, building telescopes and taking long trips like that would actually cost real money. I want you to work on some inexpensive pipe-dream that sounds good in political speeches, feasibility be damned."

    Knowing they were beat, Lewis and Clark resigned themselves to designing successively large cannons. The never reached the moon, and the midwest filled out slowly, but few ever crossed the rockies, much to the delight of the native tribes, who were successful in fighting off the settlers for quite some time. Until the large cannons came of course :)