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Space Science

Difficulties of the Nuclear Powered Prometheus Project 54

Posted by michael from the nukes-in-space dept.
brandido writes "Space.com is reporting on some of the technological difficulties facing the nuclear powered Prometheus Project. In particular, it is focusing on the fact that the Prometheus project promises to represent a paradigm shift in the capabilities of interplanetary probes. Such a large shift in capabilities entails the development of new technologies and designs, a process that is often full of mishaps and setbacks."
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Difficulties of the Nuclear Powered Prometheus Project More

Difficulties of the Nuclear Powered Prometheus Project

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  • Just one problem... (Score:4, Interesting)

    by JScarpace ( 463675 ) on Thursday July 03, 2003 @11:24AM (#6358778) Homepage
    What happens when something like the Challenger disaster occurs to a launch vehicle carrying a nuclear reactor?

    • Re:Just one problem... (Score:4, Interesting)

      by Kiriwas ( 627289 ) on Thursday July 03, 2003 @11:32AM (#6358844) Homepage
      As far as I know, there are protective measures you can take surrounding the actually nuclear material. There's no doubt it will come tumbling out of the sky, but it won't be radioactive dust, it will be more like a giant, heavy metal box that goes BANG..still fully encased. We've been building enclosures to keep explosions INSIDE for years, I see no reason we can't build enclosures to keep explosions OUTSIDE.
    • probally not as bad as this
      http://nuketesting.enviroweb.org/atmosphr/

    • Not A Lot (Score:5, Informative)

      by turgid ( 580780 ) on Thursday July 03, 2003 @11:56AM (#6359089) Journal
      Firstly, unused nuclear fuel is not very radioactive relatively speaking and is not very toxic.
      Secondly, the fuel can (and is) built into very strong and resilliant "cans" and can be further protected to the point that even a fall from a great height such as earth-orbit will not result in any radioactive release.
      Thirdly, any engineer woth their salt will design the darned thing such that it will not start its nuclear reactor (when the nasty fission products start to be produced) until the craft is either a significant distance away from earth already, or has achieved escape velocity and can not fall back to earth.
      I am a qualified nuclear engineer with several years reactor physics experience at a nuclear power station.

      • Re:Not A Lot (Score:2, Funny)

        by Anonymous Coward
        I am a qualified nuclear engineer with several years reactor physics experience at a nuclear power station.

        Is that you, Mr. Simpson?

    • Re:Just one problem... (Score:5, Informative)

      by BigBir3d ( 454486 ) on Thursday July 03, 2003 @12:22PM (#6359322) Journal
      Just like last time...

      1965 [mit.edu]
      • One big difference, the nuclear material in this case is not used for the rocket that will propel the spacecraft into orbit. It powers the rocket that pushes the spacecraft out of orbit or to move around target planet. The nuclear material is never used inside the Earth's atmosphere.

      • Uh, first of all, the reactor would only contain uranium at launch. Uranium, with a half life of over a billion years, is barely radioactive at all. The main danger from uranium is actually not radiation, but heavy metal poisoning. Secondly, the fuel is contained in cans that are easily capable of withstanding rocket failures. Thirdly, there have been dozens of craft safely launched with radioisotope thermal generators for power. These typically use plutonium as a heat source. They have failed before, with

    • Re:Just one problem... (Score:2, Interesting)

      by stripe ( 680068 )
      Reading those articles makes me admire mankinds ingenuiy, to be able to build robotic explorers of such capabilities. It also makes me despondent over how those with irrational fears limit us. There is a significantly greater chance of a nuke being set off delibrately in a city by madmen than one of these nuclear powered spacecraft hitting a city. Radioactive pollution of Mars? Wake up guys, its pretty much a dead planet! Landing probes on those icy moons will give us the greatest possiblity of finding life
  • Further detailed exploreation of the solar system is something that needs to be done, if only to give us humans more things to chew on.

    Personally, I hope we don't find any sort of lifeforms beyond the microsopic, at present Humans have enough trouble dealing with other humans, let alone a compleatly differnt being from a vastly differnt evolutionary chain.

    But I do hope that this technology gets up there, and gets used, one more step in the refinement of space tavel, even if it doesn't work, at least it wa
    • Yes, but facing something as totally alien as another sentient species just might give humanity the kick in the collective head it needs to start THINKING instead of just reacting.

      I mean.... faced with something so radically different as a completely non-terrestrial form of life, racial differences between humans start to look pretty pissant, don't they?

  • This is why we need manned missions... (Score:5, Insightful)

    by RobertB-DC ( 622190 ) * on Thursday July 03, 2003 @11:40AM (#6358935) Homepage Journal
    Unless you buy into the notion that all the Mars probe failures were due to xenophobic Martians, we've recently witnessed several examples of unmanned, robotic craft turning into expensive piles of junk for reasons ranging from the sublime [space.com] (legs bounced harder than expected) to the ridiculous [space.com] (meters? feet? what's the difference?).

    Contrast those catastrophic failures with events on human-occupied craft. Fires [space.com] and collisions on Mir, and of course Apollo 13 [usra.edu] for those who get their science from the local multiplex -- yet the craft kept flying, due to human involvement and ingenuity. The conclusion is clear: the more complex the system, the more likely you need a non-silicon-based intelligence to keep it from self-destructing.

    To address the issue at hand: NASA wants to send a nuclear-powered spaceship to Jupiter? Cool, but you'd darned well better include a crew compartment, unless you *want* to see what happens during a space-based meltdown.

    The bottom line is that there is no way to predict everything that can go wrong with any complex system. That's why we need more manned missions. Spend less money on absolutely "perfect" systems, and more on systems to support a human presence to fix it when it breaks.

    After all, Captain Cook explored the south Pacific with nothing more than boats of wood, and men of iron. He also had a whip, and generous quantities of very strong beer...
    • No, we don''t. If for the price of one manned mission we can build 10 unmanned missions and 50% of those fail, we're still ahead by 4 missions. And did the presence of humans help with Columbia or Challenger?
      • The reason we need manned missions is because sending people into space is cooler and more exciting than sending robots into space.
        Why should robots get all the fun?
      • The only honest reason to send machines into space is to pave the way for people. The exploration of space is no more about science than was any other migration in history.
        • Your comment is accurate, but depressing.

          The early explorations of the Americas, IIRC, were intended to 1) find a shorter route from point A to point B, 2) exploit the resources, and 3) establish settlements. Unfortunately, none of these lead directly to getting more manned missions:

          1) Space, like the American continents, isn't a shortcut to anywhere (although communicaions satellites do provide a "shortcut" for information -- but not people).

          2) It's still cheaper to rape Earth-bound resources than it i
          • You are correct to say that space isn't a shortcut. Rather, "space" is everything, period. We just happen to be confined, thanks to technological immaturity, to one tiny mote of dust in one tiny little backwater.

            With that in mind, maybe a better analogy than European migration to the Americas would be the broader human migration from Africa throughout the globe. If there were political debates about the wisdom of expanding beyond the immediate neighborhood of the Olduvai, I'd guess that some folks reject
          • It's not gold, but $20 trillion from precious metal asteroid mining [cnn.com] might provide a motivation for someone to "exploit the resourses"

      • Re:This is why we need manned missions... (Score:5, Insightful)

        by RobertB-DC ( 622190 ) * on Thursday July 03, 2003 @01:40PM (#6360221) Homepage Journal
        And did the presence of humans help with Columbia or Challenger?

        As cool as the shuttle program is, I'm afraid it's turned out to be another example of overengineering: so heavily dependent on supposedly failsafe systems that a single failure (O-ring, foam strike) destroys the entire system.

        Contrast with the comparatively simple Soyuz launch system. It may seem primitive, but by golly, the thing usually works. And when it doesn't, you can still survive [nasa.gov] (though "15-17 Gs" doesn't sound like a picnic in the Russian countryside).

        And the reference to Cook's terrestrial explorations has another parallel with space exploration: sailors on his ships (or any ship of the time) had no guarantee that they'd make it back home. They don't call it a "widow's walk" for nothing. I'm not sure we can get anywhere on the "new frontier" until we're able to accept the sort of losses that were common on the "old frontier".

        Of course, this is easy to say, sitting in a comfy chair in an air-conditioned office, listening for the boss' footsteps so I can minimize my browser when she walks by...

    • Re: $$$ (Score:3, Insightful)

      by TwistedGreen ( 80055 )
      Manned missions are vastly more expensive than any automated probe, for obvious reasons. What's the loss of a few million dollars due to miscalculations or unpredictable conditions compared to the potential for loss of life, or the reduced frequency of missions? And anyway, is sending a human up with your probes only for purposes of maintenance really worth the added expense? It would be cheaper to just send two or even three probes at once than to design the mission to support human travellers.

      Sure, we
    • By that logic we'll never colonize space until we get some brutal, global tyrant who's run out of places to stash political prisoners.... or bury the bodies.
    • Contrast those catastrophic failures with events on human-occupied craft. Fires [space.com] and collisions on Mir, and of course Apollo 13 [usra.edu] for those who get their science from the local multiplex -- yet the craft kept flying, due to human involvement and ingenuity. The conclusion is clear: the more complex the system, the more likely you need a non-silicon-based intelligence to keep it from self-destructing.

      With Apollo 13, keep in mind that it completely failed all of its scientific objectives.

  • How about the damn name? (Score:5, Funny)

    by JUSTONEMORELATTE ( 584508 ) on Thursday July 03, 2003 @12:21PM (#6359316) Homepage
    IIRC, Prometheus' story didn't exactly have a happy ending. (obSlashjoke: This project will surely open a Pandora's Box)
    Maybe we could call it Magellan Mark IV or something a bit more optimistic?

    --
  • Try something unmanned first. Then worry about setbacks.

  • fuel? (Score:2, Interesting)

    by bobba22 ( 566693 )
    If the nuclear reactor is meant to provide energy to the ion thrusters, what fuel will the ion thrusters be using? If the project is meant to last for decades thanks to nuke, it would take a lot of xenon to supply the ions. Surely the decaying ions would not provide enough for thrust, if re-used in that way? Or can solid fuels be vapourised by the heat of the reactor? I quite like the idea of the reactor rods (or whatever) blasting themselves into space with electricity they've just generated.
    • These craft typically use heat to make electricity, and then use the electricity to power a thruster of some kind; the thruster accelerates propellant. Ion thrusters have been made to use a great many different things as reaction mass (propellant), ranging from argon to bismuth to Buckyballs to xenon. The Deep Space One probe which was so phenomenally successful used xenon in its ion engine.

    • Re:fuel? (Score:3, Informative)

      by jwdg ( 676461 )
      See, for example: this ESA article [esa.int]: Solar-electric propulsion is ESA's new spacecraft engine. It does not burn fuel as chemical rockets do; instead the technique converts sunlight into electricity via solar panels and uses it to electrically charge heavy gas atoms, which accelerate from the spacecraft at high velocity. This drives the spacecraft forwards. In a chemical rocket, burning the fuel creates gas that is expelled relatively slowly compared to electric thrusters. However, in an ion engine, the gas
  • We have had the technology for about 30 years now to do something like this. It's only because of the general publics' fear of nuclear power that it hasn't happened yet. get the ball rolling.. send out a few test probes... learn... and go deeper...

  • Interesting topic... (Score:3, Informative)

    by Unknown Kadath ( 685094 ) on Thursday July 03, 2003 @05:13PM (#6362804)
    ...and just in time for me to go home, too.

    Here's a NASA page [nasa.gov] on Project Prometheus.

    Have a good weekend, all.

    -Carolyn

  • Nice idea, no chance it'll fly. (Score:3, Insightful)

    by phrackwulf ( 589741 ) on Thursday July 03, 2003 @08:22PM (#6363995)
    Prometheus has been on the drawing boards at the Jet Propulsion Lab since the early eighties. The reason it didn't get anywhere then is the same reason it won't get off the ground now. It's nuclear. Let's give an example. Recently, there was a major press blow-up (no pun intended) in Michigan about allowing the transport of used fissile material across the state. Never mind that said material was cast in the center of rain barrel or bigger sized pieces of concrete. Never mind that you could drop the damn containment vessels off a five story building and they wouldn't break. Everyone was screaming about the possibility of radiation getting into the water and air. The poor NRC guys had a public relations nightmare. And all because Ralph Nader and his merry bunch of marauders has made "nuclear" anything the scariest thing in the public imagination since Anthrax. You can't build new nuclear reactors and there is no chance you can get a nuclear powered craft whether propelled or simply powered by radiation off the ground. Too many people are too dumb to understand how infitesimal the possibility of disaster is, because all they remember is Chernobyl and Three Mile Island. Sad but true my friends. And now we get treated to the same feast of ignorance about cloning or genetically modified foods by people who let ignorance and fear rule their imaginations. [-)
    • Sadly, I'll have to agree with you. This will get much more bad PR than NASA's RTGs like they put in spacecraft such as Cassini. This is because NEP uses SCARY NUCLEAR REACTORS OF DEATH!!!

      Of course, a nuclear reactor is much safer than even RTGs because at launch, the reactor would only have virtually benign uranium. While of course, the RTGs are fuelled with plutonium. (RTGs are very safe, mind you. They can withstand a rocket failure intact without a problem.)
    • Hey, they've revived the concept of nuclear powered aircraft. They're talking about a nuclear version of the predator UAV. Apparently it will use decay stimulated by x-rays rather than a critical mass, so it'll be contain substantial quantities of radioactive material even before it's switched on.

      This thing will spend it's service life on or very near Earth, and when it's shot down, this is where the shit will land. Which has a higher risk, launching something once, or spending months at a time in combat a
    • Of course, public fear of nuclear power has absolutely nothing to do with the people responsible for Chernobyl, Three Mile Island, and the people who'll happily build a nuclear reactor on top of a fault line as long as the right bribes will get you the necessary permits. Nope, it's all Nader's fault.

      Right.

      Look, I agree that much of the public response to nuclear energy is irrational, but it's hardly as simple as you portray it. I'd happily live next to a nuclear power plant -- if the people who financ

      • And how many serious accidents like Chernobyl have happened? Meanwhile, coal miners die young from black lung disease and the United States is pathetically dependent on foreign oil. I'm not going to say nuclear disasters are impossible, I'm not going to disagree that the NRC has made the occasional mistake. But the shear Luddite malice directed at this technology is insane! Imagine if car crashes were as rare as nuclear incidents?
  • Say, don't remember this one? Like the experimental engine working for all of a second before going belly-up? Ok, maybe they've had more satellites since then but they kept pretty low profile about it.
    • I am not sure what are referring to in your post but Ion engines have been used both by NASA in unmanned exploration and on commercial satellites. Project Prometheus is looking to develope larger, more efficient versions of what is already in common use.
      • You sure you're not confusing Ion and Hall engines? There was an experimental probe with an ion engine a while ago. Only the engine shut down almost immediately. I'm too lazy to dig up the article but it was within last 12 months for sure.
  • Did anyone think to compensate for the instability of the naquadria that powers the hyperdrive?
    • Oh...Yeah............RIGHT !!!!
      Next let's check the Fooselezer and the Rat-atatter and hope for the best when the Bring-atilly goes online for the quarkdrive.
  • Anyone remember the project a few decades ago to create an Orion-class spaceship that used nuclear explosives ( You know, all those valuable bombs we have laying around ) as it's fuel supply? Just build the thing in orbit to begin with and give it a shove before you start it's engine.

    It can move fast, once you get over the problem of sudden acceleration killing the crew.

    You can build it big enough to hold hundreds of people and the hydroponics to sustain them. ( You just use bigger/more bombs to propel

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