Homer Hickam Speaks Out For Fission Rockets

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."

Comments

that's nice

[Syre]

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.

Re:Good Idea, just won't happen anytime soon

[Ian Bicking]

When someone first thinks about nuclear waste, one of the first reactions is, "why not just launch it into space?" I haven't happened to come upon the argument against it, but I imagine it goes like: sending stuff into space is far more expensive and polluting than people imagine.

But this would be perfect -- sure, you'd be making more nuclear waste, but you'd be sending it into space in the process! That's not hard to understand.

I think there is every reason to worry about dangers, though. Rockets do blow up (with current technology) and if they had radioactive materials onboard that would mean many, many deaths (mostly indirectly through increased cancer).

I imagine that nuclear rockets could be considerably safer than chemical rockets, since my vague impression is that they wouldn't be as explosive. But many of the standard ways that nuclear reactors are made safe -- mostly through containment of various sorts -- would be hard to do in a rocket.

Perfectly Serious

[jeff.paulsen]

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.

Re:Fission? He's GOT to be kidding!

[Rothfuss]

Homer Hickman:

"During his long NASA career, Mr. Hickam worked in propulsion, spacecraft design, and crew training, and won many awards including the Astronaut Office's coveted Silver Snoopy award for his outstanding support of the astronaut corps, and a special commendation for overall excellence from the Director of the Marshall Space Flight Center. His specialties at NASA included training astronauts on science payloads, and extravehicular activities (EVA). He also trained astronaut crews for many Spacelab and Space Shuttle missions, including the Hubble Space Telescope deployment mission, the first two Hubble repair missions, Spacelab-J (the first Japanese astronauts), and the Solar Max repair mission. Prior to his retirement in 1998, Mr. Hickam was the Payload Training Manager for the International Space Station Program."

Mike Eckardt:

"Like many of you, I wanted to be an astronaut when I was young. It wasn't the glamor of a high profile, high risk job. It was the adventure. I lost that dream sometime during my teen years, when I realized that I wasn't enough of a Superman to join America's astronaut corps. But hope springs eternal. With the increasing availability of space flight in the 21st century, and the advent of a commercial tourist industry in space, I may yet manager to make my way into the high frontier."

Thanks for your input Mike. We'll get back to you.

-Rothfuss

Oh my God, I'm so affraid!

[Erris]

- 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.

What a dishonest article

[Edmund Blackadder]

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.

Re:What a dishonest article

[jeff.paulsen]

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.

Bad Idea, here's why--

[schmaltz]

First, there's the well-documented high failure rate of launch vehicals -about 5% for the US, 10-20% for rest of the world. This figure doesn't include experiments or tests.

Second, the atmospheric reentry of one lost rocket schlepping clicking-hot material up the well can lead to the atomization and dispersal of that material in the atmosphere, transforming the earth into a mutants' menagerie.

The Space Shuttle has experienced a lower failure rate than the rest of US launchers, about one in one hundred.

There was an uproar a few years ago, about the Cassini probe. That probe, containing over 32 KG of plutonium, was lifted by a launcher which, at the time, had a one in twenty failure rate, and was due for another.

Additionally, there have already been three catastrophic failures of launchers with plutonium-containing payloads, resulting in world-wide atmospheric dispersal of a hundreds of curies worth of plutonium.

Personally, I don't have a problem with the idea nuclear power or fission-powered space travel. But there remain serious development before it becomes considerably safer. This isn't a marketing campaign, you can't convince knowledgeable people with images of spouting teapots, not when life on this planet is at risk. Nor will risk management white-wash keep people from realizing there's a definite, likely risk that people will die from an accident. [I work in risk management.]

So, what's more important, do we need to do this now, now, now? Or can it wait a decade or three, until we have nuke power better figured out? My vote is to wait a bit.