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Continuous Burn Nuclear Drive

An Orion drive propulsion system that "burns", instead of exploding
  (+4)
(+4)
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The fissile material is fed into the chamber in wire form instead of pellets and continuously ignited. This limits the pulsing problem that would shake a standard Orion spaceship apart. There would still be some shaking unless you could feed the wire in at the speed of light but the pulses would be much shorter.

I'm aware of the utter innocence of this idea. How do you cool the combustion chamber? How do you feed the material into the chamber? How do you sustain a nuclear reaction where the material explodes at the speed of light and needs to be replenished just as fast? How do you get the stuff to blow up in the first place? Dhunno.

I guess the idea is to look at the possibility of creating a sustained nuclear burn rather than a series of explosions. Admittedly a bit like inventing a hovering skateboard without wheels and saying: "Let scientists figure out the floating part." so this is more just wondering if this is something that's been looked at or is worth looking at.

doctorremulac3, Jan 14 2014

The 'Davy Crockett' rifle http://en.wikipedia...tt_(nuclear_device)
How small? At least this small. [Alterother, Jan 14 2014]

Here's one being tested. http://www.youtube....watch?v=eiM-RzPHyGs
[doctorremulac3, Jan 14 2014]

Other nuke drive ideas http://en.wikipedia...ar_pulse_propulsion
[doctorremulac3, Jan 14 2014]

Here's project Orion http://en.wikipedia...nuclear_propulsion)
[doctorremulac3, Jan 14 2014]

Atom bomb cutaway http://www.atomicar...sion/Fission9.shtml
[doctorremulac3, Jan 14 2014]

Goodbye to all that http://grammar.abou...a/goodbyegraves.htm
About 1 paragraph down the description of a canister bomb. Have these, but instead of false teeth have the French load them with heavy atoms. Provide them with tweezers. [bungston, Jan 15 2014]

For [DIYMatt] Fusion_20Beam
My take on "continuous fusion" propulsion - deuterium-loaded palladium wire + lasers. [neutrinos_shadow, Jan 19 2014]

Fission-fragment rocket https://en.wikipedi...ion-fragment_rocket
Mentioned in my anno [notexactly, Oct 24 2016]

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       Orion works because the vaporized bomb (casing, accessories, fissile products and remaining fissile material) provide the reaction mass, shoving the craft forward. It works better in atmosphere, where the air can do the same.   

       Your approach doesn't have most of that material, and doesn't have the explosive force to throw what little there is against the pusher plate.   

       There's also the fact that fission doesn't really burn, as such, you either get a slow output of heat, a faster output of heat, or a boom. You can cause the wire to "burn" with a high ouput of heat by surrounding it with a neutron reflector, but it doesn't throw off material to provide thrust, and definitely not directional thrust.
MechE, Jan 14 2014
  

       //Your approach doesn't have most of that material//   

       I'm saying have the same amount of material, just feed it into the reaction continuously instead of in chunks and in such a way that it booms, not burns. The idea of a nuclear drive is that you take your reaction mass and move it much faster than you can with a chemical explosion.   

       I guess the analogy is this: you could have a ship powered by sticks of dynamite thrown out the back, or with one continuous reel of primacord fed very quickly into the explosion.   

       Could there be a nuclear equivalent?
doctorremulac3, Jan 14 2014
  

       It would be hard to channel neutrons without having some sort of gravity affecting field (the availability of which would negate the need for Orion)   

       You could use nuclear power for a variety of other non-pulse techniques -- for instance to power a laser that is lighting a sail.
theircompetitor, Jan 14 2014
  

       There are very few places, other than the HB, where the phrase "a standard Orion spaceship" can be used casually.
MaxwellBuchanan, Jan 14 2014
  

       LOL. True that.
doctorremulac3, Jan 14 2014
  

       If you have most of that material, then you are just as well off using vaporized aluminum as your reaction mass, and a standard nuclear reactor as your fuel source. There's no benefit to the boom, and a significant loss, in that it's less directional.
MechE, Jan 14 2014
  

       //There are very few places, other than the HB, where the phrase "a standard Orion spaceship" can be used casually.//   

       I've just googled "standard Orion spaceship" and apparently the only other place on the web is Ebay.
In 'collectables'.
Loris, Jan 14 2014
  

       I have to disagree and agree with [MechE]. Let's just say I have my moments. The big thing about an Orion drive is its ability to exert force on a pusher plate. The pusher plate is usually made of Unobtainium. I don't think that this force on the pusher plate can be attributed in any significant way to the mass of casings/accessories (disagree). Atmosphere I can give, lots of light particles imparting a specific moment. But the main bit is fissile material and to a smaller extent 'unspent' fissile material. I know Orion is touted as a reaction mass vehicle, and so it should be, but....in the conversion of mass to energy one takes into account that mass that was converted to energy, but also that mass (usually a very heavy nucleus accelerated to very high velocities) not converted to energy but delivering a momentum, or at least a specific moment.   

       Now herein lies the rub, me hearties. Momentum must be conserved, so must mass and so must energy. We mix all of that in a pot, and what we really want is a bang, not a slow fissile (sic: fizzle.) Unfortunately you really need that big bang for Orion to be Orion. Else you have invented a way to power an ion/plasma drive, which is baked.   

       [Edit: [MechE] alluded to vapourising (x)with the nuclear power, which is similar to this idea]
4whom, Jan 14 2014
  

       //I've just googled "standard Orion spaceship" and apparently the only other place on the web is Ebay. In 'collectables'.//   

       Not only that, but somebody seems to have bought it - it's no longer listed.
MaxwellBuchanan, Jan 14 2014
  

       The pusher plate is not unobtanium. It's a few yards of steel, frequently backed up with concrete or water for neutron absorption. Then the massive shock absorbers.   

       The problem with Orion was political/environmental, not technical feasibility.   

       As far as what provided the thrust, I quote an article by Michael Flora   

       "Stanislaw Ulam and Cornelius Everett eliminated the combustion chamber entirely. Instead, bombs would be ejected backwards from the vehicle, followed by solid-propellant disks. The explosions would vaporize the disks, and the resulting plasma would impinge upon a pusher plate."   

       "Taylor adopted Ulam's pusher-plate idea but instead of the propellant disks he combined propellant and bomb into a single pulse unit. The propellant material of choice was plastic, probably polyethylene."   

       The accessories are rather definitely a critical part of the thrust.
MechE, Jan 14 2014
  

       [MechE] So you would agree that the big thing is to apply force on the pusher plate?
4whom, Jan 14 2014
  

       I do like the idea of a continuous nuclear bomb.   

       How about this as a configuration: start with two very long rods of enriched uranium. Each rod is just narrow enough that it doesn't go critical (ie, neutrons leak out just faster than they're produced).   

       You bring two of these rods together to form a V. At the tip of the V, the geometry is just good enough for the thing to go critical. As the rods vapourize, you feed more in - sort of like welding, only rather more so.
MaxwellBuchanan, Jan 14 2014
  

       [Max...] I am not against sustained fission or fusion reactions. You must already know that I am of the firm opinion that a continued fission reaction masquerades as a massive liquid/solid ball of iron at the core of our very Earth. And, of course, there is the sun (fusion). I am not convinced, however, that we could feed fissile material into any V shape, whatever shape, continuous reactor. Just the back pressure will ameliorate the feedstock. It would be like trying to push a granite block up a hill with a rope.
4whom, Jan 14 2014
  

       That may well be true. But I'm pretty sure you didn't mean "ameliorate".
MaxwellBuchanan, Jan 14 2014
  

       Quite so, I meant Amelia Earhart .
4whom, Jan 14 2014
  

       Yes, and the point is that nuclear explosions, by themselves, don't exert a lot of thrust.
MechE, Jan 14 2014
  

       //nuclear explosions, by themselves, don't exert a lot of thrust.//   

       Yes [MechE] and neither do ion propulsion systems. Lets carve Orion into two distinct uses. Leaving Earth's gravity well, and interstellar propulsion. I am a big fan of its use for both. Detonation of nuclear fissile products aside. This is really the best way to get from A to B when A is on the surface of Earth and B is somewhere else.   

       However, a slow burn is not it. Sure, you could use the extreme temperatures to ablate some light metal in a particular direction. But, well, well, well. Maybe that is what the good doctor was hinting at. After escaping the heliopause, maybe slow burn orion is good, not seeing it myself...
4whom, Jan 14 2014
  

       They also don't have a high specific impulse. There is nothing a continuous nuclear detonation could do for a launch vehicle that a ground based laser couldn't do better.
MechE, Jan 14 2014
  

       Absolutely, it seems we are actually on the same side.
4whom, Jan 14 2014
  

       I don't see a way to sustain a continuous fission reaction without using more energy than it will produce. If we're going to the trouble of inventing new technologies to produce a nuclear reaction why not skip fission altogether and make a fusion engine?   

       However, I disagree with those of you saying that fission won't provide enough thrust. The orion drive concepts I'm familiar with utilize Beryllium in the pusher plates to reflect neutron radiation, which is a significant part of the reaction, maximizing the amount of radiation thrust produced. It may not be as spectacular as a nuclear bomb going off in the atmosphere but it could still provide more thrust than current ion/plasma engines for a long period of time.
DIYMatt, Jan 14 2014
  

       This would be fission, not fusion. Basically an atom bomb stretched out into a thread many miles long and coiled up for storage aboard the spacecraft.   

       It might sound like what you'd get if Salvador Dali were designing spacecraft but is it possible to have a long skinny nuclear bomb that you detonate an inch at a time? Then could you throttle it up and blow up it up by the foot, yard etc? You're just slamming two materials together, it seems like you should be able to do that in linear form. Have one side be the core of the cable and the other side be the cladding then compress them together as they enter your ignition area.   

       Associated question: how small can you make a nuclear bomb? Because the core of this idea is basically having an atom bomb about the size of a pencil except several miles long.
doctorremulac3, Jan 14 2014
  

       The device itself? Small enough for one man to carry onto a battlefield. See <link> for the Davy Crockett, a 'nuclear rifle' that launched a 76 lb. tactical nuke about three miles, which, as it turns out, puts the three-man crew inside the blast radius.   

       Well, it's not a perfect system.
Alterother, Jan 14 2014
  

       Only a small fraction of a nuclear explosion is neutron radiation. Much of it is thermal, and more is photonic (not even Gamma). Without an atmosphere for the thermal to push out, only a very small fraction of the thermal is going to act as thrust, and only the portion of photonic directed at the pusher plate would provide energy input. In order to maximize the thrust from an Orion nuclear reaction, you need to convert as much as possible of the energy into kinetic energy bouncing off the pusher plate.   

       There's also the issue that I've never heard of an Orion design with a neutron reflector pusher plate, probably for the simple reason that it is such a small fraction of the bomb's energy.
MechE, Jan 14 2014
  

       Thanks for the link Alt. Added another one to follow up. Pretty interesting.
doctorremulac3, Jan 14 2014
  

       RFK was at that test as a spectator. The device was launched by remote control, as apparently there were a lack of volunteer operators.
Alterother, Jan 14 2014
  

       // launched a 76 lb. tactical nuke about three miles, which, as it turns out, puts the three-man crew inside the blast radius//   

       Was the word "duck" included in the instructions?
MaxwellBuchanan, Jan 14 2014
  

       I think your biggest issue is one of criticality. How is your continuous wire achieving criticality out in the open, and not on the reel, inside your spacecraft?   

       Criticality in modern nuclear weapons is achieved with much less than the "open sphere critical mass" of fuel. To further complicate things, you actually need a "prompt critical mass" to get an explosion, which is much smaller (or larger, depending on how you look at it - you need more neutron flux, put it that way), and impossible to achieve without assembling the reaction mass very very quickly ie via explosives. It is generally achieved by compressing a smaller ammount of fuel to a much higher density, and also assisted by cleverly using neutron reflectors, neutron flux "initiators" ("whizzers") etc and tampers (and some really clever combinations of the above, yes I'm looking at you, Uranium tamper). Think of modern, post - Teller-Ulam weapons design as essentially being "how little (expensive) high grade fissionable material can I get to detonate, in order to initiate a (relatively cheap, and rather scalable) fusion secondary device, to produce massive neutron flux to fast-fission my (cheap) fissionable bomb casing". If a primary could be made that was 1/10 the size of existing, it would still be useful for the above, the energy budget is that sufficient, especially with boosting.   

       I could imagine bringing two or more long rods together at an apex and achieving a sustained reaction, perhaps inside some special reaction chamber, but a) it would not be explosive but rather energetic at best and b) said rods themselves would be close enough to critical on their own to be a dangerous radiation source.   

       Unless, of course, you can come up with an ideal Neutron reflector. My "Unobtanium fission rocket" was my take on what you could do if such a material existed, and perhaps a continuous reaction solution.
Custardguts, Jan 14 2014
  

       I'm thinking the you'd make it go critical the same way you do in an off the shelf nuke. Conventional chemical explosion.   

       Have your fissile core, cladding and explosive wrapped around it doing an implosion thing.   

       Picture an implosion nuke cutaway. Now just picture that as a cutaway not of an orb, but of a long wire, everything being pretty much the same only different. The different part being how do you keep the whole thing from blowing up at once.   

       Again, like I said, this is kind of like the hover skateboard with the part about how it floats not quite worked out.
doctorremulac3, Jan 14 2014
  

       Would this not be more like a standard orion spaceship but with a small star mounted on its behind instead of a bomb? i.e. shiney but not doing very much useful work?
pocmloc, Jan 14 2014
  

       No, there would be a lot of force slamming into the back of the spaceship propelling it forward. See links.
doctorremulac3, Jan 14 2014
  

       Ignoring all of my above concerns, if you are feeding rod into an active nuclear explosion, you must have:   

       A) One heck of a study gasketing system.   

       B) Very sturdy rod, such that back pressure doesn't shatter or jam it into the feeding mechanism.   

       C) A rather complex convoluted neutron barrier that the rod feeds through, such that you don't periodically get an exceptionally high neutron pulse detonating the rod further up.
MechE, Jan 14 2014
  

       d) no particular advantage over a discrete device system, but with a multitude of additional complexity, of which a) through c) are probably the easiest to deal with.   

       //Have your fissile core, cladding and explosive wrapped around it doing an implosion thing//   

       Um, you do realise there's a hell of a lot more going on in the pit of a detonating nuclear device, than a solid sphere of fissile material with an explosive cladding, right? I thought I hinted at that with my previous anno.   

       I mean if you're happy with fuel consumption efficiencies at below 5%, sure, get on with it, use a solid. But the technology has moved on a long way from that.   

       You physically cannot, with conventional explosives, get a solid core of fissile material, to become dense enough, and stay together long enough, to achieve high percentages of fuel consumption. It simply dissasembles itself before enough fuel can be consumed. The problem lies with inertial confinement, and all the trickery and skullduggery needed to hold enough material together, for long enough, under the right conditions, to get adequate burn up, otherwise you just get a fizzle, of one sort or another, approximating a fairly bad sort of dirty bomb (which both of the WWII devices were, essentially).   

       Modern Teller-Ulam design "thermonuclear" devices are THE most efficient use of both expensive highly fissile fuel (U235 or P239), fusionable fuels (Deuterium, Lithium isoltopes, and traces of Tritium), as well as fissionable secondary fuels (lower grades of Uranium). The design is so neat it almost looks on purpose, as it's basically the "sweet spot" of most if not all of the competing requirements. Project Orion proposed to use efficient, small thermonuclear devices, and it's fuel efficiency would be orders of magnitude above anything you could possibly conceive in a "monolithic" arrangement you're talking about. It just doesn't work that way.
Custardguts, Jan 14 2014
  

       //You physically cannot, with conventional explosives, get a solid core of fissile material, to become dense enough, and stay together long enough, to achieve high percentages of fuel consumption//   

       Not sure what you think they use to trigger an atom bomb but it is conventional explosives. See link.   

       Anyway the idea is to stretch that cutaway shown in the last link into a long pencil shaped cable and feed it out rather than shooting individual bombs.   

       But annos starting with "Um," are starting to come in so that's typically when I lose interest in the idea and move on.
doctorremulac3, Jan 14 2014
  

       Nuclear bombs aren't very efficient.
MechE, Jan 14 2014
  

       Can't think of anything more efficient than a 5 foot long device that can blow up an entire city.
doctorremulac3, Jan 14 2014
  

       Stars run for billions of years on single tank of fuel. That seems pretty efficient.
Alterother, Jan 15 2014
  

       Yes, but it's a 3.72218422 × 10^29 gallon tank.   

       In terms of potential energy in the core to total energy out, it really is bad, and the sub-optimal geometry would make it worse. [Custardguts] was entirely correct.
MechE, Jan 15 2014
  

       a 4 foot long device that can blow up an entire city?
bs0u0155, Jan 15 2014
  

       A cupful of antimatter?
MechE, Jan 15 2014
  

       Perhaps it's a question of velocity and scale. If two (or more) very, very long rods of fissile material approached each other at relativistic velocities, could an efficient, bomb-like reaction be sustained? In other words, is this idea impossible or merely highly improbable?   

       Sure, you can't push a granite block up a hill with a rope at ordinary speeds; but if you fire a steel cable at the block faster than the speed of sound in steel, the block will be pushed uphill (or, more likely, disintegrate).
spidermother, Jan 15 2014
  

       //Not sure what you think they use to trigger an atom bomb but it is conventional explosives. See link//   

       Did you read my anno? Fat man had a simple core (which still wasn't monolithic, it has a tamper, air gap, and initiator) surrounded by a prodigous ammount of high explosive, and achieved ~20% consumption of it's fuel. A modern device has a much more complex core, and consumes a much higher fraction of its fuel, but additionally, with the use of a fusion secondary element, as well as other refinements, produces orders of magnitude more yield than would result from only having the primary component.   

       There isn't really any way to implement these features in a "continuous rod" design.   

       I'm very, very confident there isn't any way to implement the concept you're proposing either, that is a continuous rod core that can be detonated in a controlled fashion, along it's length. You could possibly design an arbitrarily long nuclear device, but it would have to be detonated in one go (and in fact you'd have to do a lot of work on the detonation timing, or rather wiring of the detonators, to get it to go off at all).   

       There's no advantage to having a "rod" or "wire" nuclear bomb, and in fact, it almost certainly wouldn't work at all. We already have well established designs for somewhat efficient, and certainly reproducible and cost effective, scalable nuclear devices, down to fairly small sizes (although efficiency definitely goes up rapidly with size at the bottom end of the scale).   

       Anyhow, take a step back. I think you/we are confusing the very different scenarios of continuous and discrete processes.   

       There's no middle ground between reactors, which operate in effectively static conditions with respect to density and criticality, and bombs, which transiently achieve (and vastly excede) critical conditions in a discrete event.   

       If, after all, you're talking about in some way sustaining reaction energetic enough to be ejecting fission products out as reaction mass, that you slowly feed fuel into, that for some reason is best fed in as a rod rather than balls or cubes or something, you haven't explained how you would maintain criticality in your reaction chamber (which is why I pointed out my previous idea, which indicated one way to do exactly that, albeit with an imaginary substance). Especially when you're trying to produce maximum thrust, which would only be achieved at maximum chamber pressure and temperature (which points towards the "bomb" rather than the "reactor" design).   

       I just don't get what this is trying to achieve.   

       I'll try to keep the Um's to a minimum in the future.
Custardguts, Jan 15 2014
  

       But [custardguts], leaving aside any particular application, are you ruling out a bomb-like but sustained reaction as merely unachievable using any foreseeable technologies and scales, or as theoretically impossible? What if the rods were allowed to be arbitrarily long and arbitrarily rapidly moving (in particular, faster than most of the particles leaving the reaction, and faster than the speed of light in the rods)? What if the reaction were to occur near a black hole or neutron star? (That's a genuine question; I don't know the answer.)
spidermother, Jan 15 2014
  

       Come to think of it, a supernova is basically this idea scaled up. So I'm leaning towards thinking that the distinction between bombs and reactors is a practical, rather than a theoretical, one.
spidermother, Jan 15 2014
  

       The best way to achieve the goal of this idea is with a fusion drive. I we're dealing with "impractical with current technology" devices anyway, why not go for a more powerful cleaner burning reaction that could be throttled up and down more easily? Shirley you could feed a "rod" or continuous stream of lithium deuteride into a combustion chamber and ignite it with lasers easier than you could create a continuous explosive fision reaction.
DIYMatt, Jan 15 2014
  

       [spider] - I'll gladly concede that point. It's also not what was proposed.   

       In fact, some sort of exotic reactor could be used to consume the fuel at even practical velocities of feed, especially if there were many fuel rods being used. However, you'll never be able to achieve the two key goals, which is a) burn up as much of the fuel as possible for both weight and cost reasons, and b) achieve maximum thrust by having the exhaust products as hot as possible (unless you use a working fluid, in which case that's well trodden ground).
Custardguts, Jan 15 2014
  

       //The best way to achieve the goal of this idea is with a fusion drive//   

       Maybe, but as far as I know we haven't had any success in laser initiated fusion, at least to the extent needed to make a useful rocket motor. Not that this thing is any closer to reality.   

       Anyway, the idea behind this admittedly chocked- full-o-flaws design is to address the waste that occurs when you blow up a bunch of nuclear bombs and just ride out the shock waves getting forward movement from the cumulative effect of the blasts.   

       With teeny tiny continuous nuclear explosions you could move them much closer to the ship harnessing that energy much more efficiently and without shaking your ship apart. So rather than blowing up a thousand bombs over a few hours you'd blow up ten million bombs over a few weeks. It's like sailing on a gentle tropical breeze for a couple of days rather than just trying to get where you're going by sailing through a hurricane for an hour.   

       I will say this, a big reason the Orion concept was dropped was because we were scared of nuclear bombs, a legit fear, but I think traveling to planets is a much better use for these things than annihilating cities. Whether it's silly 30 mile long nuclear cable bombs or just nuke pellets being tossed out the back there's no denying that, right here, right now, there's no mechanism that's going to give you a greater specific impulse than a nuke.   

       Second on the list of ways to get going very fast in space right now would be an ablative plate being blasted by orbital lasers but that would take years to get up to speed. Then you're on a one way trip where you fly by the Nibblonions and wave because there's no stopping once you get going.
doctorremulac3, Jan 15 2014
  

       // you fly by the Nibblonions and wave because there's no stopping once you get going.//   

       Oh yes there is. All that's needed is a really long crumple zone on the front of the ship. It would also be useful if the Nibblonions could, in advance, paint a target on a suitable piece of unoccupied land.
MaxwellBuchanan, Jan 15 2014
  

       And if that doesn't work, you better wave quick because the chances of them looking up at the precise second to see you frantically waving are pretty small.   

       Space missions shouldn't end up like Benny Hill sketches. (with artistic license Star Wars style sound in space doppler effect) "grreeeaaTIIIINNNNGS FRROOooommm earrrrrth..."
doctorremulac3, Jan 15 2014
  

       UM!   

       1. Inefficiency - it seems like a benefit of the Orion system partly turns on that inefficiency. Weighty fuel, casings, other assorted bits hurled out the rear as reaction mass.   

       In my flight of ideas this reminds me of Robert Graves description of the contents of a German canister bomb. Linked!   

       2. Pulse vs continuous. A truly continuous nuclear explosion is what HG Wells envisioned in his description of the first nuclear war. But you could approach continuous with weak pulses very tightly spaced - bitty baby bombs. Like an internal combustion engine.
bungston, Jan 15 2014
  

       I got the "UM!" part but sort of lost you after that.
doctorremulac3, Jan 15 2014
  

       There was a proposal for a thing called a Bussard ramjet, that is similar to this idea. The ram jet was to scoop up interstellar hydrogen and feed it into a continuous nuclear fusion reaction for thrust. If I recall correctly.
afinehowdoyoudo, Jan 16 2014
  

       // scoop up interstellar hydrogen //   

       That's gonna need one hell of an intake manifold.
Alterother, Jan 16 2014
  

       ^ magnetic.
FlyingToaster, Jan 16 2014
  

       Even with superscience technology the ship would be mostly hood scoop. Here come The Judge!
Alterother, Jan 16 2014
  

       The Bussard Ramjet was a popular scifi idea 20 years ago, then we learned that the concentration of hydrogen in interstellar space is actually too low for that to work.
DIYMatt, Jan 17 2014
  

       It's not so much the concentration of hydrogen, it's the difficulty of fusing hydrogen. Most fusion plans focus on deuterium, which is extremely rare in interstellar space.   

       And the fact that we don't actually know how to generate a magnetic scoop of the size required.
MechE, Jan 17 2014
  

       Well, if we are going to get some new space flight technology, I'm afraid it won't be from NASA. Just watching one of my favorite shows "Engineering Disasters" which featured NASA's hilarious foray into comedy. In this episode, they slammed two probes into the surface of Mars after deciding the agency could be streamlined by cutting back on expensive calculations about when and how long to fire retro rockets. I'm afraid NASA is the Old Yeller of beloved government agencies. We all know it's time to put it down but nobody has the heart.
doctorremulac3, Jan 17 2014
  

       I disagree, NASA does good development work. They're also doing decently at directing money to private launch companies. They are currently driving research in solar sails and ion engine, and providing technical assistance in developing scramjets (which is admittedly more launch than interplanetary focused).   

       Your description of why the two probes were lost are inaccurate. Both problems were quality control issues, one in checking that the output from a system was to contract, and one in failing to correct a known bug. In neither case was it a cost cutting measure. Considering how many things have to go right for something like a mars lander to fail, it's hardly surprising that a couple have been lost.   

       One of the key developments in the last decade is moving NASA away from truck driving and back into it's role in high end research, development, and exploration.
MechE, Jan 17 2014
  

       Yes, NASA's doing a great job as long as we have Russians willing to take us to space. And to be fair, the $125 million Mars orbiter allowed us to study first hand what happens when you put metric instructions into a system designed using inches, feet and miles per hour so I'll guess we'll give them an A for effort.   

       Both this and the Mars Polar lander crashed under the faster/better/cheaper program. Sounds laudable enough but at some point this stuff should probably work.   

       //high end research// I'd like to have tried that when I was a kid. "Hey, did you mow the lawn?" "No, I'm doing high end research." The job at hand is mastering space. That means boots on the ground someplace other than Earth. If it's "truck driving" that's required to get us there then that's the job we should be working on.   

       NASA's battle cry during the 60s was "First to the Moon!" Today it should be "Great job, you're all extra special!" I want something other than excuses for my tax dollars.
doctorremulac3, Jan 17 2014
  

       SpaceX will be handling manned launches before you know it, they're already handling cargo. As is Orbital Science Corp.   

       NASA does the research that private enterprise can't do. Private enterprise, on the other hand, is really good at the faster, better, cheaper thing.   

       Oh, and as far as that stuff working, yes they crashed two probes a decade and a half ago. Since then, they've landed a rover designed for 7 days which lasted 90, a 90 day mission that lasted 5 years, and a 90 day mission that is still ongoing just shy of 10 years later. You're getting things for your money other than excuses.   

       They've also got ongoing research in what's needed for sustaining long term deep space missions, which is the key step to "boots on the ground".
MechE, Jan 17 2014
  

       Well Jeeze Mech, we're in total agreement. I see the future being totally in the hands of private organizations.   

       Hey, nobody loves NASA more than me, I just think they need the occasional kick in the pants.   

       Speaking of which, I'm going to the gym to burn off the last of this holiday weight gain.   

       And if I'm not back by Sunday, Go Niners!
doctorremulac3, Jan 17 2014
  

       cup full of antiquarks
Voice, Jan 17 2014
  

       60 year old arks, read it again!
pocmloc, Jan 17 2014
  

       " Both problems were quality control issues, one in checking that the output from a system was to contract, and one in failing to correct a known bug "   

       " Mars orbiter allowed us to study first hand what happens when you put metric instructions into a system designed using inches, feet and miles per hour "   

       Don't forget the Hubble optics error while you're at it.   

       <obligatory QA guy comment on> Funny how these issues always get called quality control issues...you never hear them referred as engineering screwups. <obligatory QA guy comment off>
normzone, Jan 17 2014
  

       That's because the term "quality control issue" predates the existence of an actual "quality control person". When use it, we're not saying that "quality control" screwed up, we're saying that the quality control procedures failed, allowing some other issue to make it through to production. It makes no difference if those procedures are an actual quality control guy, or simply design reviews (and I've worked in places where it's only been the latter).
MechE, Jan 17 2014
  

       I think the goal is not to explode because that is uncontrolled populations of reactions. Obtaining the generation of vast magnetic and electric fields via controlled nuclear energy would be a step forward.   

       Because science learns more and more about the tiny and becomes more manipulative, super fine control of particles and even nuclear forces will give us the motor we need to grow out into the universe.
wjt, Jan 18 2014
  

       // I guess the idea is to look at the possibility of creating a sustained nuclear burn rather than a series of explosions. //   

       I think a fission-fragment rocket might be what you want. [link]
notexactly, Oct 24 2016
  


 

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