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Homer Hickam Speaks Out For Fission Rockets

Posted by michael on from the riding-the-torch dept.

jonerik writes: "Former NASA engineer Homer Hickam (perhaps best known for his 1998 memoir "Rocket Boys," which was turned into the 1999 motion picture "October Sky") has this article in Technology Review in which he advocates that the U.S. revive its nuclear rocket program of the '50s and '60s, arguing that nuclear-powered rockets are the only realistic way of opening up the rest of the solar system - particularly Mars - to human exploration."

5 of 403 comments (clear)

  1. that's nice by Syre · · Score: 5, Insightful

    Nice to see an old-timer get a little coverage on /., but he really covers no new ground in that short article.

    The major objections then, as now, are:

    - What happens if fission powered rockets crash? Instant nuclear disaster, unless the containment vessel holds (and it might, but the public will not be convinced it would).

    - Other countries fears that fission powererd rockets are actually orbiting nuclear weapons, able to be dropped on them at will. And again, even if they weren't bombs, orbiting fission rockets would be nuclear weapons: all you have to do is build the containment vessel so it can be blown apart on impact via conventional explosives, leaving a cloud of contamination.

    I don't predict these space nukes are coming any time soon. Better to invest in laser propultion and linear magnetic launchers.

  2. Perfectly Serious by jeff.paulsen · · Score: 5, Insightful

    You're missing a couple of critical points:

    1. First, your reaction mass is your reactor shielding. There's a whole lot of water or liquid CO2 between the pile and the crew.
    2. Second, the craft only has to carry reaction mass for one way. You get to Mars, you turn on your compressor (powered by your atomic pile), and pump the local atmosphere into your tanks. This is a huge advantage. CO2 provides a lower specific impulse than, say liquid H2, but it's plenty to get back to Earth, or to push on to Titan.

    In short, there are huge advantages to a nuclear rocket over a chemical rocket. Check out NERVA and NIMF, the two best treatments of the subject.

    --
    -- Jeff Paulsen
  3. Oh my God, I'm so affraid! by Erris · · Score: 5, Insightful
    - What happens if fission powered rockets crash? Instant nuclear disaster, unless the containment vessel holds (and it might, but the public will not be convinced it would).

    Oh, you mean like Chernobyl? Not to make light of 100 or so deaths, but there are worse things in the world. It's hard to get worse than Chernobyl: Big core with high burn-up (that's lots of fision products from running), Zero containment, chemical explosions and fire at ground level.

    Or perhaps you were thinking of all of the thousands of above ground nuclear bomb tests that the people have performed?

    - Other countries fears that fission powererd rockets are actually orbiting nuclear weapons, able to be dropped on them at will. And again, even if they weren't bombs, orbiting fission rockets would be nuclear weapons: all you have to do is build the containment vessel so it can be blown apart on impact via conventional explosives, leaving a cloud of contamination.

    Holy Armagedon, Batman! Do you think that this is a more practical means of nuking your friends than the tens of thousands of purpose built warheads lying around?! What shall we do?

    I suggest we quit fooling around with bullshit fears and get some good use out of Nuclear technology. Projects Kiwi and NERVA were technical sucesses killed by ludite nonsense. We can go to Mars, we can exploit the solar system and we should do so. The sooner the beter, population expands geometricaly. We can use nukes to solve our problems peacefully, or we will use them the other way as we run out of exploitable resourses here. Chose your children's future.

    --
    DMCA, Hollings, Palladium. What might have sounded like paranoia is now common sense.
  4. What a dishonest article by Edmund+Blackadder · · Score: 5, Insightful

    It is really annoying when some one arguing from authority (i am a rocket scientist, listen to me) gives you misleading information.

    Nuclear engines are much more dangerous than chemical ones.

    If a chemical rocket develops problems on ascent ground control push a button and blow it up.

    What if that rocket has a shitload of uranium or plutonium on board?

    We have sent nuclear material up in rockets withsome nuclear powered stelites but they have a really negligable ammount of radiactive stuff in them, compared with what is needed for a mission to mars.

    And if you think that rockets do not blow up on ascent any more you have not seen NASA's record recently.

    So there you have it - thats a risk that he did not mention although it is a very relevant factor. Now you may say - the risk is not that great, or it is worth it, but it should have been mentioned in an honest article.

    And also the thing he said about getting energy from space is such BS. If he knows as much about nuclear power as he pretends to he should know that we have enough uranium to give us energy for a loooong time and nuclear powerplants are much safer than nuclear rockets.

    1. Re:What a dishonest article by jeff.paulsen · · Score: 5, Insightful
      Nuclear engines are much more dangerous than chemical ones. If a chemical rocket develops problems on ascent ground control push a button and blow it up. What if that rocket has a shitload of uranium or plutonium on board?

      But why would we want to blow it up? It's not like it's full of rocket fuel or anything - it just has some radioactive stuff in it. The radioactive stuff is solid, and even if we make a full-acceleration nosedive into basalt (which we won't, because all we have to do to stop the thrust is dump the reaction mass, not to mention parachutes), the worst that's going to happen (assuming decent reactor design, like a pebble bed reactor, if they scale that small) is that you get a few chunks of radioactive material; there isn't enough energy involved to get a pulverizing effect. Men with geiger counters go find it and clean it up.

      Nuclear rockets are safer than chemical rockets (provided that the reaction mass used is something basically low-energy, like CO2 or H2O, rather than H2 or H2O2). It's like the difference between a low-pressure solar steam engine and a dragster running on nitromethanol, and you're asking about what to do if the steam engine catches fire because of the flaming exhaust it doesn't have. The risk of boost-phase abort requiring the destruction of the craft in atomic rockets is very, very low.

      If you want to have something to attack nuclear rocketry on, look into on what effect the very slightly radioactive exhaust trails will have in the ionosphere. Man-made Van Allen belts? Could be, if there's enough energy. Would there be? What would those do? How radioactive would each particle of reaction mass be? How many of them would there be, and what would happen to them, during the atomic rocket's atmospheric boost phase? What kind of reactor would it have? What are this reactor's modes of failure? Is there a reactor that is, by design, immune to modes of failure we want to be particularly concerned about?

      Not all of these questions were addressed by Hickam, either, but that doesn't make the article dishonest.

      --
      -- Jeff Paulsen