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Project Orion: The True Story of the Atomic Spaceship

Johnzo writes: "It seems ludicrous to imagine that a spaceship could ascend into orbit and beyond by riding the impulses produced by a series of external atomic explosions. Such an idea would perhaps be more properly confined to science fiction -- like the Niven & Pournelle classic Footfall. But Footfall drew its inspiration from a real-life project, a project that, according to George Dyson's Project Orion: The True Story of the Atomic Spaceship, continues to offer exciting possibilities for space exploration." This sounds like a fascinating book; read on below for johnzo's full review. Project Orion: The True Story of the Atomic Spaceship author George Dyson pages 345 publisher Henry Holt & Company rating 9/10 reviewer johnzo ISBN 0805059857 summary An excellent high-level introduction to the characters, engineering, culture, and future of the Orion project, and an ideal jumpoff point to other readings about the atomic age.

The chief advantage of an Orion-style spaceship can be explained in terms of specific impulse, which is the time during which a mass of fuel will produce enough mass x g thrust. Conventional chemical rockets, constrained by exhaust temperature, can produce specific impulses of about 430 seconds. Orion-style engines promised a specific impulse that was an order of magnitude higher than that--"2000 to 3000 seconds for first-generation designs, 4000 to 6000 for larger vehicles using existing bombs." The combination of long specific impulse and high thrust was unique to Orion, and would have allowed for the sustained high-acceleration maneuvers necessary for long-range manned space flight. And, like nuclear bombs in general, Orion scaled up more easily than it scaled down. The original Orion reference design massed 4,000 tons, and unlike the Apollo missions, which sent 600 lbs into space for every pound that came home, more than half of Orion's launch weight would have returned to Earth from a voyage to Saturn. Had it fulfilled its promises, Orion would have enabled manned space travel on a grand scale, with thousands of tons of payload and year-plus mission durations. It would have let us go into deep space in spaceships instead of mere disposable, unmanned spacecraft.

From 1958 to 1965, a team of physicists and engineers at General Atomic in California pursued the Orion dream. Project Orion tells their story ably. Dyson explores high-minded science and baroque bureaucracies in short, manageable, anecdote-loaded chapters. It's a terrifically easy read; with just freshman physics and a passing knowledge of 1950's America, I was able to follow along with no problems. The book begins by explaining the basics of Orion, the 1950's atomic establishment, the dot-com-like culture at General Atomic, the experiments that gave rise to the Orion idea, and the seed funding from ARPA. Dyson moves on to introduce us to some of Orion's chief characters, notably Stanislaw Ulam, who originally patented the atomic-pulse-drive idea, Ted Taylor, the Orion project leader and namer (he "just picked a name out of the sky," says the book) and Freeman Dyson, the celebrated scientist who was on board for the first two years -- and, who, not coincidentally, is George Dyson's father.

From there, it's on to the fun parts, beginning with the chapters detailing the engineering problems that Orion's designers faced. Most obviously, how do you design a pusher plate that won't shake itself apart or ablate under repeated impacts of nuclear plasma? (answer: with a thin coat of oil, reapplied between each atomic pulse.) How do you cushion the crew from the hundred-g shock of the pulse-unit explosions? (answer: with two-stage shock absorbers.) How do you shape the expansion of the propellant plasma so that you hit the pusher plate right? (answer: you take advantage of directed-energy weapons research to shape your atomic charges.) How do you eject your atomic charges from around the rim and orient them so that they explode correctly? (answer: you talk to Coca-Cola about bottling plant design.) And how do you cope with a pulse-unit misfire that sprays your pusher plate with jagged shrapnel instead of friendly plasma? (no answer given.)

Since GA's Orion program was a small shop that wasn't straightjacketed by job descriptions, the physicists were free to envision operational details and space missions for their baby. After concluding its engineering coverage, Project Orion looks at some of these missions. Freeman Dyson proposed a mission that would have landed on the moon, orbited Venus, Earth, and Mars, and then gone out to to Enceladus, Saturn's second-innermost satellite. The mission would have made clever use of tricks like planetary gravity boosts, in-atmosphere decelerations, and propellant harvesting to stretch its range. The senior Dyson was vexed by the problem of atomic contamination, though; even if it used the cleanest bombs available in the late fifties, an Orion launch would still introduce considerable amounts of toxic fission products into the Earth's magnetosphere. Dyson estimated that about ten people would die from atomic contamination for every Orion launch. This was about one percent of the estimated fatalities attributed to the atomic tests of the day. Instead of waiting for cleaner bombs to solve this problem, GA collaborated with friendly factions inside NASA--including rocket pioneer Wernher von Braun, who was an enthusiastic supporter of Orion--to discuss rocket-boosted Orion models. Proposals were made to either loft Orion into orbit wholesale or to boost it in pieces and conduct final assembly in orbit. Rocket-powered auxiliaries were also discussed; these would serve as landing craft and inter-Orion taxis.

In the end, of course, all of this work amounted to nothing. For various reasons -- nuclear test bans, lack of funding, and indifferent brass -- the Orion project was never permitted to conduct any of the nuclear test shots necessary to advance its work. The Orion staff made only a single successful test flight during the entire duration of the project, and this was conducted with 1m-diameter model powered by C4 charges. By 1959, Freeman Dyson had left the effort; he had seen that NASA wasn't going to budge away from Von Braun's giant rockets, and he knew that NASA was the only agency that would be able to support Orion. The project staggered on for four more years under Air Force funding, but the Air Force wasn't the right fit for Orion; no one could figure out a clear and present military use for all that lifting power. The USAF repeatedly approached NASA for money, but NASA was interested only in the conservatively incrementing known technologies, not in wholesale revolution. Orion was orphaned by 1965, its knowledge scattered through hundreds of classified documents and dozens of scientist's brains.

The book ends on a fascinating note, with modern-day retrospectives from various Orion staff. Some of them--including Ted Taylor--have renounced the idea of atomic weapons entirely. Some of them are convinced that Orion could never be made to work safely and reliably. Others believe that Orion is an idea whose time will come. NASA agrees with them, in some small measure; they're looking at Orion again as a space-exploration and asteroid-intercept technology. They're having a tough time finding details and data from the General Atomic project, though -- much of Orion's data is still classified. Dyson has had more success in hunting down those documents than NASA. When he contacted them in the course of his research, they begged him for copies!

I greatly enjoyed reading Project Orion. The only disappointment it held for me was its heavy reliance on Freeman Dyson's recollections, and the consequent weighting of the book towards Dyson's year of involvement. I suspect there's a lot of interesting detail missing from the latter six years of the project. That aside, Project Orion is an excellent high-level introduction to the characters, engineering, culture, and future of the Orion project, and an ideal jumpoff point to other readings about the atomic age.

You can purchase Project Orion: The True Story of the Atomic Spaceship from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

212 comments

  1. Wow by Anonymous Coward · · Score: 0

    I wonder if thats a good idea.
    It seems that blowing stuff up under you could be painful.

    1. Re:Wow by spike+hay · · Score: 2

      It seems that blowing stuff up under you could be painful.

      These bombs are small enough that they only produce a large thud after each explosion. IIRC, they also have shock absorbers to cushion the crew area. Still though, losing your lunch in space would not be very fun.

      --
      If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
  2. Deep Impact by TheCrazyFinn · · Score: 1

    Deep Impact also used Orion.

    Nice to see a book on Ol' Bang Bang.

    The Crazy Finn

    --
    "You've got an invalid haircut" -Warren Zevon - Life'll Kill Ya
    1. Re:Deep Impact by docbrown42 · · Score: 1

      Um, not it didn't. The engines used in Deep Impact were way too smooth for an Orion-type engine. I think the writers either thought the name was cool (and didn't realize it had already been used), or found a some info on Orion engines but didn't understand it.

      After seeing the movie, I'm betting on the latter explaination. I doubt the writers understood basic astronomy and physics. I mean, c'mon, how could you see the asteroid both day and night? Was it circling the earth?

      -Ed

      docbrown.net NEW!
      Graphic Design, Web Design, Role-Playing Games...all the good stuff

      --
      Ed Wedig
      Graphic design services
      docbrown.net
    2. Re:Deep Impact by joekool · · Score: 1

      That's mostly because that movie was a weird combination of Lucifer's Hammer, and the above mentioned Footfall. At least that was what I thought after rereading them recently.

      --

      Slackware: old school feel, new school gear.
  3. politics vs. science by NixterAg · · Score: 5, Informative

    I read this book a few months ago and I agree with the reviewer that this is an excellent book. However, it tends to concentrate a great deal more on the politics surrounding Project Orion than the science much to my chagrin. Much of the information surrounding Project Orion is still classified so I don't necessarily blame the author for this, but those intending on reading the book should qualify their expectations.

    I did get a great appreciation for the sheer size and magnitude of truly difficult engineering problems and the organizations and minds assigned to solving them.

    All in all, it's a quick and easy interesting read that engineers and NASA junkies will likely enjoy.

    1. Re:politics vs. science by Anonymous Coward · · Score: 0

      I can't believe you said "much to my chagrin"

    2. Re:politics vs. science by Jack+William+Bell · · Score: 4, Informative
      I know George and have met his father Freeman Dyson. And I can tell you that Freeman is still very reticent about the scientific details of the project, mostly because of the work they did designing miniature atomic weapons. Plus it is kind of a cold war mindset/cultural thing. Really it is amazing how much detail George was able to pull out of the hat when researching this book. He even came up with some test video (which I have seen). According to him the goverment attempted to re-restrict some of the information he collected after he got it via the Freedom of Information Act. Too late... Heh heh.

      Still the politics of the project are illuminating themselves in how they show changing attitudes in the US and the US government over those crucial years.

      Note for the interested: George Dyson lives in Bellinham WA (from where the fictional Orion-based spacecraft was launched in 'Footfall') and was GoH (Guest of Honor) at Vikingcon 17 there in the summer of 2000. Freeman Dyson has been a GoH at Vikingcon many times. Jerry Pournelle has been GoH at Vikingcon once and Larry Niven has been GoH twice, including 17. As you can guess 17 was a very cool con for Orion-based sychronicity and George gave a wonderful presentation there on the research he was doing at the time for this book.

      Jack William Bell, who must admit to being the Vikingcon 18 chairvictim...

      --
      - -
      Are you an SF Fan? Are you a Tru-Fan?
    3. Re:politics vs. science by NixterAg · · Score: 1

      Sorry. I had to convince everyone I was smart to whore karma.

  4. Footfall a classic? by Anonymous Coward · · Score: 0, Troll

    No way. Niven and Pournelle (especially Pournelle) have been coasting on their reputations since "A Mote in God's Eye."

    1. Re:Footfall a classic? by Bobo_The_Boinger · · Score: 0, Troll

      I agree, I started reading the book ("Footfall") and eventually just stopped. Didn't interest me in the least.

      --
      --David
    2. Re:Footfall a classic? by Anonymous Coward · · Score: 0

      I loved "Footfall." I read it twice over the years.

      I thought it was fascinating in its creation of the her mentality invaders, and the use of existing technology to solve a problem in our current age. I loved the opening scene where the invaders blast Voyager for target practice as they enter the solar system.

      I agree that recent Niven and Pournelle offerings have sux0r'd. But, Footfall was my favorite. (I thought that The Mote series blew chunks)

      So, next time, you must agree with me, or I will plant a foot on your chest.

    3. Re:Footfall a classic? by foistboinder · · Score: 1

      Much of Footfall was a rehash of Lucifer's Hammer.

    4. Re:Footfall a classic? by DuckDuckBOOM! · · Score: 2, Informative

      Lucifer's Hammer is an offshoot/expansion/whatever of the asteroid impact scene in Footfall. According to N&P in a making-of article (source escapes me, but I think was an old Analog,) they were pitching the story outline for Footfall, and the editor wrote back, "Forget about alien invasion. Write about asteroid impact."
      The rest, as they say, is history.

      --
      Life is like surrealism: if you have to have it explained to you, you can't afford it.
    5. Re:Footfall a classic? by DatabaseCowboy · · Score: 1

      As the lone desenting voice in the crowd, I must say that although it's been many years, I remember enjoying Footfall. Granted I haven't read Lucifer's Hammer, so I'm not familiar with the similarities. I seem to remember finding the "pack mentality" of the aliens vs the "indiviuality" of the humans and interesting conflict. I think that it is somewhat concievable that, in the end, whoever learned to think like the other first might win such a confrontation. That is unless the one with the higher tech didn't just destroy the planet and move on (which the aliens sure as Hell could have done). I thougth the Thors (think that's what they were called, crowbar sized objects dropped from orbit with just enough inteligence to recognize shapes and adjust toward them) were more interesting than Orion. THOSE were smart bombs. Still think they'd be a good idea if lifting them into space didn't cost so much. I don't know that they'd hit with quite as much force as the authors described, but hey, cool idea.

    6. Re:Footfall a classic? by Cpt_Kirks · · Score: 1

      Check out the "Sparta" series with S.M. Stirling. I think a new one is due out soon.

      The "WarWorld" books, set in the same reality, are pretty good too.

    7. Re:Footfall a classic? by Caradoc · · Score: 2

      The "smart crowbars" were discussed in depth as a possibility for the SDI projects - see references for "brilliant pebbles" as opposed to "smart rocks."

      --
      Specialization is for insects. - R.A.H.
    8. Re:Footfall a classic? by Nyarly · · Score: 2
      Still think they'd be a good idea if lifting them into space didn't cost so much. I don't know that they'd hit with quite as much force as the authors described, but hey, cool idea.

      Actually, IIRC, I remember reading an article about Thor-like non-explosive deorbited projectiles that would release energy like a 10 megaton nuke. Something about building them out of tungsten, and contructing them in such a way that they conversed the jerk of their impact into outward force. My understanding was that the result of suddenly accellerating on impact would be sufficient to cause solid tungsten to explode. Nutty, crazy stuff.

      Also, IIRC the Thor devices had nothing more than a radio-controlled rocket to deorbit. Niven's favorite gravitational phenomenon (tidal force) keeps them aligned like spokes around the Earth, and you scatter them in varying orbits. All the intelligence is on the ground: you need to deorbit the right thor at the right moment in order to hit your target. On the other hand, it's the technological equivalent to hurling a metal projectile ten years ago only to snap your fingers today and have it fall out of the sky on your enemy.

      --
      IP is just rude.
      Is there any torture so subl
    9. Re:Footfall a classic? by Anonymous Coward · · Score: 0

      I agree. Mote got their collaborations off the ground, but they've become more irrelevant with each one. (Anybody remember Inferno?)

      The sad thing is that it's Larry Niven's career that's suffered the most. (Don't weep, he's rich and I'm sure he's happy. He's got quite enough laurels for his earlier work.) Though I can heartily recommend Rainbow Mars from a couple years ago, it's damn funny and shows more joie de vivre (hope I spelled that right) that the last six books put together.

  5. Would a reactor-style system work better? by Whispers_in_the_dark · · Score: 3, Interesting

    I'm not a physicist, but I would think that the majority of the energy from the explosion would not propel the spaceship but would be emitted in perpendicular directions, escecially as the blast grew in size (let's not forget the sudden G forces involved here). Wouldn't using the resulting hot gasses/radiation from a nuclear reactor provide a smoother, more efficient burn?

    1. Re:Would a reactor-style system work better? by nrd907s · · Score: 1

      I'm not a physicist but I'm assuming the reason for the conical shape of the bottom of thrusters is to allow for perpendicular exploded particles to also help propel the ship. (something like why satellite dishes are conical/parabolic)

    2. Re:Would a reactor-style system work better? by RocketJeff · · Score: 3, Interesting
      The majority of the energy does go in other directions, but the typical nuclear explosive has more then enough energy to spare. The pusher-plate on the bottom of the Orion ship was designed to cushion the ship from the raw acceleration (as well as the radiation).

      The typical nuclear reactor rocket (like the NERVA) was designed for space-only operations and didn't have the power to lift-off from the Earth's surface. Remember, the Orion ship itself is the size of a large skyscraper.

    3. Re:Would a reactor-style system work better? by DonkeyJimmy · · Score: 1

      but I would think that the majority of the energy from the explosion would not propel the spaceship but would be emitted in perpendicular directions

      You could always direct the explosions using the same design as a rocket engine.

      Wouldn't using the resulting hot gasses/radiation from a nuclear reactor provide a smoother, more efficient burn?

      It sounds like they're trying to make a practicle design, and leaving a trail of radiation may not be the best solution for that.

      I think the best concern you raise is the G force issue, which I'm also curious about. Anyone know any details on that?

      --
      "Probably the toughest time in anyone's life is when you have to murder a loved one because they're the devil." -Philips
    4. Re:Would a reactor-style system work better? by breadbot · · Score: 1
      You could always direct the explosions using the same design as a rocket engine.

      You might have a hard time finding nozzle material that could stand up to a fusion explosion! A pusher plate seems like about the best you could do -- you might actually want to allow some of that force to dissipate.

    5. Re:Would a reactor-style system work better? by Louis_Wu · · Score: 4, Informative
      Good theory, wrong application. Using a conical shape to control explosions is a well known and widely practiced technique, but it isn't used in rockets or thrusters.

      The reason that a rocket engine has a conical 'bell' is to control the behavior of the exhaust gases. Specifically, the shape of the exhaust bell controls the efficiency of the gas flow, and prevents losses which could reduce thrust. All of the exploding happens inside the rocket, and it is the escaping gasses which the exhaust bell is designed to affect.

      FYI, one of the main uses of explosion control is shaped charges, the kind that police special units use to get through walls/roofs/ceilings. A simple shaped charge can be made by placing two explosives in a 'V' shape, the resulting explosion will be pointed toward the opening in the 'V'. It's not magic, the explosion is very radial, but more heads toward the open end of the 'V' than any other direction. To get a charge which points most (nearly all?) of the explosion in one direction, put something strong and heavy around the explosive where you don't want damage. Example - a piece of angle iron (an 'L' shape of steel) with strips of C4 along the inside of the 'V' will shape the explosion and direct it toward the open end. Unfortunately, Newton's Third Law still applies (for every action there is an equal and opposite reaction), so the force of the explosion will want to move the angle iron. So you weight it down with sandbags. This is pretty much how LAPD started using shaped charges to enter buildings through the roof. A few pieces of angle iron with explosive in them, some sandbags, arrange on the roof, get behind something and BOOM. This was later refined - the shaped charges (iron pieces, wiring, & everything) were attached to a piece of particle board, placed on the roof, a few sandbags were dropped on top, and you could create yourself a nice entry hole for your SWAT team in a few seconds.

      Caveat: I haven't experimented with shaped charges, I've just read about them.

    6. Re:Would a reactor-style system work better? by spike+hay · · Score: 3, Interesting


      You could always direct the explosions using the same design as a rocket engine.


      Rocket nozzles would not be able to withstand the force of a nuclear explosion. However, there is a different concept that even gets a greater ISP than Orion. It is called the Nuclear Salt Water Rocket.

      This uses plutonium salts dissolved in ordinary water. In the fuel tank, there are lots of boron rods to keep the fuel from fissioning. But then the fuel is fed into the combustion chamber, which has no moderator. Here, the nuclear salts explode, producing a high speed jet of water from a constant nuclear explosion.

      This would get a specific impulse of around 10,000. It has an even bigger advantage over Orion: Orion's fuel is uranium or plutonium. That's very expensive. However, the vast majority of the NSWR's fuel mass is just water. This makes it quite a bit cheaper than Orion.

      However, we already have had the tech for Orion since the 60's. (In fact, the completely designed a craft to reach Saturn) So, maybe we could get an exemption from the test ban treaty and build and launch one.

      --
      If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
    7. Re:Would a reactor-style system work better? by XNormal · · Score: 3, Informative

      Wouldn't using the resulting hot gasses/radiation from a nuclear reactor provide a smoother, more efficient burn?

      Smoother? Yes. More efficient? definitely not.

      Specific impulse depends on exhaust velocity. Exhaust velocity depends on temperature. The maximum achievable temperature for a nuclear thermal rocket is limited by the reactor construction materials to a few thousand degrees. With an Orion rocket, even if it loses a significant percentage of of thrust sideways the temperature is still orders of magnitude higher.

      --
      Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
    8. Re:Would a reactor-style system work better? by bigredorb · · Score: 1

      Actually explosive energy can be directed in a very precise direction. At least this is true for conventional explosives. It's called a 'shaped charge' and I think its at least 1940's technology.

      http://www.llnl.gov/str/Baum.html has some interesting pictures, but the jist of it is shaping your explosive in a concave fashion so that the shockwave bounces off itself (if you can't imagine that do a google for 'shaped charge').

      In the military I used shaped charges that drilled an almost perfect cylindrical hole in the ground about 1' or less in diameter and about 1 meter into the ground. It was really strange to see. The sides of the hole would be perfectly smooth.

      Is a shaped nuclear charge possible, that sounds pretty intense!

    9. Re:Would a reactor-style system work better? by ryanwright · · Score: 2

      Is the quality of this cocaine satisfactory, Mr. Delorian?

      You should get your facts straight and learn to spell before slandering a man who was acquitted of all charges due to entrapment. In other words, a government setup: John DeLorean was not a coke head nor did he traffic in it.

      --
      -Ryan, with the unoriginal sig
    10. Re:Would a reactor-style system work better? by Darkfred · · Score: 1

      But your high speed jet of water is still moderated by conventional explosive physics. Even more so because of the limited expansion of water. So although you could get a huge specific impulse. (as with any reaction drive large enough) to get this high would take an immense array of nozzles and more fuel then its worth.

      We already have the atom bombs just lying around right now. That I think was the point. Plus you get a reaction mass that is all the available air the atomic explosion can affect. You could never approach this by burning on-board fuel.

      --
      ----- 70% of all statistics are completely made up.
  6. The Ultimate Frat-Boy Vehicle by Hack+Shoeboy · · Score: 1, Funny

    A Spaceship that lights its own farts???

    --

    IN TEH FUCHAR, LITERSY WLIL EB OPSHANAL!!!!!111
  7. Other nuclear propulsion... by wowbagger · · Score: 5, Interesting

    If you are ever in Idaho, you should visit EBR-1, the world's first breeder reactor. It is decommissioned, cold, and open for tourists during the summer season. Outside, they have some prototype nuclear jet engines - devices that took in air, heated it with a fission reactor, and expelled it for thrust. Neat stuff - would have been nasty as hell had it ever gone into service, but neat none the less.

    EBR-1 is about 4 hours drive from the west entrance of Yellowstone National Park, and about 45 minute from Craters of the Moon National Park, so there's plenty of other stuff to do in the area.

    1. Re:Other nuclear propulsion... by Anonymous Coward · · Score: 0

      That's her journal. "Wowbagger" used to be "Double bagger," but with those translucent plastic grocery bags they have these days, it's like, "Wow."

    2. Re:Other nuclear propulsion... by dpbsmith · · Score: 2

      Well, actually even though it never did go into service, it WAS nasty as hell when it experienced a partial core meltdown on November 29, 1955.

      For some reason, most of the sites like this that show it lighting four light bulbs or mention Arco, Idaho as "the first city to be lit by atomic power" don't seem to mention this...

    3. Re:Other nuclear propulsion... by Fesh · · Score: 2

      I thought that sounded familiar. We Almost Lost Detroit had a rather detailed treatment of the incident, if I recall.

      --
      --Fesh
      Kill -9 'em all, let root@localhost sort 'em out.
    4. Re:Other nuclear propulsion... by Anonymous Coward · · Score: 0

      Nope, that was the Fermi 1 reactor.

      Partial meltdown in 1966.

    5. Re:Other nuclear propulsion... by Hasai · · Score: 1

      Sounds like you might have come across some equipment from an attempt to build a nuclear ramjet. It was called
      Project Pluto.

      --

      Regards;

      Hasai

  8. man won't... by Anonymous Coward · · Score: 0

    man won't advance till all of the useless eaters have been removed from the planet

  9. baby elephants in tennis shoes by Anonymous Coward · · Score: 0, Funny

    maybe we had better wait for hordes of invading baby elephants before taking off in an old banger...

  10. Someone explain this to me please by Winterblink · · Score: 2, Insightful

    I've heard of the Orion concept before and quite frankly I can't understand how you build something to withstand an atomic explosion for propulsion purposes and not have it blow itself to smithereens. I DO realize that we're not talking about megaton sized explosions here. :) However I'm still fuzzy on how a very low power explosion could keep the damage to the craft down while still providing an effective means of propulsion. Or is this similar to the impulse engines of star trek (the greatest scientific precursor ever, *snicker*), where the nuclear reaction is fed constantly by small amounts of reactive mass?

    --
    "I'm a leaf on the wind. Watch how I soar."
    -Hoban Washburn
    1. Re:Someone explain this to me please by RocketJeff · · Score: 2, Informative
      Or is this similar to the impulse engines of star trek (the greatest scientific precursor ever, *snicker*), where the nuclear reaction is fed constantly by small amounts of reactive mass?
      Nope, Orion was designed to use atomic bombs for propulsion.

      They wern't meant to be exploded directly against the ship, but a 'safe' distance away. The blast/shock wave is what actually propels the ship. The pusher-plate absorbs the shock and transmits it to the rest of the ship like a giant shock-absorber.

    2. Re:Someone explain this to me please by Winterblink · · Score: 1
      They wern't meant to be exploded directly against the ship, but a 'safe' distance away. The blast/shock wave is what actually propels the ship. The pusher-plate absorbs the shock and transmits it to the rest of the ship like a giant shock-absorber.

      Thanks! I guess my followup question to that would be: how "clean" can that possibly be? I imagine using nukes to break earth orbit can't be too good for those of us on the ground. :)

      --
      "I'm a leaf on the wind. Watch how I soar."
      -Hoban Washburn
    3. Re:Someone explain this to me please by benwb · · Score: 4, Funny

      It's attitudes like this that explain why my children won't have mutant powers.

    4. Re:Someone explain this to me please by RocketJeff · · Score: 1
      I imagine using nukes to break earth orbit can't be too good for those of us on the ground. :)

      The surface bursts used to get Orion off the ground would have been bad - lots of fallout and other nasty stuff. The air bursts (when the blast doesn't actually touch the ground) wouldn't have been that bad except for the initial EMP and radiation burst. Air bursts don't create fallout and are thus much cleaner then surface bursts (but I still wouldn't want to be around one).
    5. Re:Someone explain this to me please by Winterblink · · Score: 1

      Hey I'm no treehugger, I just know that airbursts and spacebursts are bad for my computers. :)

      --
      "I'm a leaf on the wind. Watch how I soar."
      -Hoban Washburn
    6. Re:Someone explain this to me please by Anonymous Coward · · Score: 0
      There are situations where you wouldn't care too much about the people left behind on the ground:

      1. They're already all dead
      2. They'll soon all be dead
      3. They'll soon all be dead if you don't get your big-ass ship into orbit
      4. You just don't give a shit about damn groundhogs. (WTF can they do to you once you've built your moon city?!!)
      5. You work for the US government

      (I can definately see someone like the Chineese going that route.)
    7. Re:Someone explain this to me please by spike+hay · · Score: 2

      I've heard of the Orion concept before and quite frankly I can't understand how you build something to withstand an atomic explosion for propulsion purposes and not have it blow itself to smithereens.

      It is exploded some distance behind the craft. The Orion has an ultra-heavy pusher plate (one of it's main drawbacks) that has a thick coating of graphite. With each blast, some of the graphite is ablated.

      --
      If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
    8. Re:Someone explain this to me please by Phurd+Phlegm · · Score: 2
      It is exploded some distance behind the craft. The Orion has an ultra-heavy pusher plate (one of it's main drawbacks) that has a thick coating of graphite. With each blast, some of the graphite is ablated.


      You should read the book. A suprising result was that with a little bit of an oil coating, there would be no ablation. Well, I was suprised, anyway.

    9. Re:Someone explain this to me please by spike+hay · · Score: 2

      Hmm. You'd think an oil coating would just vaporize. That's amazing.

      --
      If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
    10. Re:Someone explain this to me please by jcast · · Score: 1

      The coating is continuosly re-supplied.

      --
      There are reasons why democracy does not work nearly as well as capitalism.
      -- David D. Friedman
  11. All this and more... by bourne · · Score: 5, Informative

    Another good book that bears on this subject is Robert Zubrin's Entering Space: Creating a Spacefaring Civilization. He discusses the atomic bomb drive as well as other postulated ideas for interstellar craft, such as solar wings and some trick with laser and mirrors (IIRC).

    Even better, for slashdot folks, is that Zubrin takes this stuff seriously in a scientific sense. He discusses the energy needs and expected capabilities of the various craft, and in general covers a lot of "practical" ground. This is the same guy who is behind The Mars Society, which actively works to enable and encourage mannned missions to Mars.

    Slashdot has covered Zubrin and Mars Society before; see this and that. He also has a mars-specific book titled The Case for Mars: The Plan to Settle the Red Planet and Why We Must. I recommend both his books to anyone who thinks we need to get off this rock.

    1. Re:All this and more... by Oggust · · Score: 1
      Agreed, Bob Zubrin is a pretty cool guy. Actually, he'd make a great slashdot interviewee! I'd love to get an update on what's been happening since "The Case for Mars".

      How do I nominate him? And where?

      /August.

      --
      "An object declared as type _Bool is large enough to store the values 0 and 1." -- 6.1.2.5, C99 standard.
  12. blasts stay the same size as i understand it. by Unknown+Poltroon · · Score: 1

    Use a hemispherical plate, explode them at teh focus, enough of the energy pushes on the plate to make this worthwile. The key here is BIG OVERKILL not efficient.

    --
    All Troll + "offtopic" mods are meta moderated as "Unfair", because you abused the system.
    1. Re:blasts stay the same size as i understand it. by sphealey · · Score: 3, Informative
      Use a hemispherical plate, explode them at teh focus, enough of the energy pushes on the plate to make this worthwile. The key here is BIG OVERKILL not efficient.
      Ted Taylor, the master of the elliptical, evasive non-release of classified information, hinted that it is possible to direct the energy release of an atomic explosion (hard as that may be to believe). So possibly some of the classified Orion knowledge concerns how to direct the energy in the desired direction.

      sPh

    2. Re:blasts stay the same size as i understand it. by mprinkey · · Score: 1

      It shouldn't surprise us that nuclear explosions can be shaped. The "implosion" triggering system used in Fat Man and most subsequent nuclear devices made use of shaped chemical explosions, as do most anti-armor munitions. These work by the focusing of shock waves through careful shaping of the explosive material, precise denotation time and locations, and "lens" of varying composition to focus the shockwaves.

      By constructing the explosive device to reinforce that shockwave, a significant fraction of the released energy can be focused in one direction. By carefully focusing the physical shock, the neutron flux, and x-ray release, it should be possible to build a nuclear explosion that goes "that-a-way" rather than just spherically outward.

  13. Costs: by Unknown+Poltroon · · Score: 4, Funny

    Feasable nuclear engineering: 500 billion
    Buncha rocket scientists: 10 millon
    Building the engine: 1 billion
    Putting Manhattan into orbit:Priceless.

    --
    All Troll + "offtopic" mods are meta moderated as "Unfair", because you abused the system.
    1. Re:Costs: by NaDrew · · Score: 1

      Putting Manhattan into orbit:Priceless.

      So, take the Orion concept and combine with James Blish' Cities in Flight and there goes Manhattan...

      --
      Vista:XPSP2::ME:98SE
  14. Niven and Pournelle said it best by TheConfusedOne · · Score: 3, Funny

    From Footfall:

    THOOM

    THOOM

    THOOM

    God was knocking,

    and he wanted in...

    BAD
    --
    --- I wish I could hear the soundtrack to my life. That way I'd know when to duck.
    1. Re:Niven and Pournelle said it best by emarkp · · Score: 1

      That part of the book convinced me that reading it was the closest I'd want to come to riding an Orion drive.

    2. Re:Niven and Pournelle said it best by melee · · Score: 1

      Blast you! I was going to post that. Footfall is a seriously bad-ass book.

      And that sentence is one of greatest uses of onomatopoeia ever written.

    3. Re:Niven and Pournelle said it best by TheConfusedOne · · Score: 1

      Blast you! I was going to post that. Footfall is a seriously bad-ass book.

      Well, you have to let me put a large steel plate under my butt before you blast please. I have to agree that it was a good read and one of the best lines in the book.

      --
      --- I wish I could hear the soundtrack to my life. That way I'd know when to duck.
  15. The term you are looking for is "ablation" by Howzer · · Score: 5, Interesting
    It's the way the shielding on every spacecraft before the Shuttle worked.

    The shielding burns up, but at a predicted rate, and it lasts long enough to get the craft on the ground. Shuttle shielding is the opposite, it's a ceramic that simply "holds" the heat (vast simplification there, but well).

    And it's ablation again with Orion. Sure, the explosions ablate part of the shielding, but it lasts long enough to get the craft where you want it to be.

    And to answer your other question, the idea is like the engine of a car. If you can hear the individual pistons firing, then you've probably got a problem! But they do fire individually. Same thing with Orion (or similar) - the bombs are chucked out the back at a pretty rapid rate. At least in the designs I remember - I haven't read the book but I will based on the review. It sounds fascinating!

    1. Re:The term you are looking for is "ablation" by Winterblink · · Score: 1
      Heh, good analogy with the car (Futurama: "Like putting too much air in a balloon!")

      In the case of interstellar travel though, that'd bite if you get to where you're going and realize they don't have the raw materials to build more ablative shielding. How do you get back? :)

      You're right though, the concept is extremely fascinating. The best part of the posting was the bit about us travelling through space in SHIPS, not CRAFT. Once we start building vehicles that essentially aren't "disposable", there'll be a heck of a space rennaissance.

      --
      "I'm a leaf on the wind. Watch how I soar."
      -Hoban Washburn
    2. Re:The term you are looking for is "ablation" by Queuetue · · Score: 2

      Most likely, we'll find carbon and steel wherever we go - that's what they used for the plate and "grease" in the tests...

    3. Re:The term you are looking for is "ablation" by blazer1024 · · Score: 1

      Correct me if I'm wrong, but I don't expect you'd find steel on a random planet/moon. Iron ore yes, steel, I don't think so.

    4. Re:The term you are looking for is "ablation" by 3waygeek · · Score: 3, Interesting

      IIRC, Ted Taylor discussed the ablation issue in The Curve of Binding Energy, referred to in several other posts. During their tests, someone had left a thumbprint on the pusher plate; they discovered that there was less (or maybe no) ablation in the area of the thumbprint. So they came up with the idea of spraying the pusher plate with oil between explosions; ablation problem solved.

      FWIW, they consulted with the Coca-Cola company to determine the mechanism for dispensing the nuclear charges -- Coke, having lots of vending machines, knows a thing or two about dispensing cylindrical objects reliably. Taylor didn't say how many quarters it'd take to get to Alpha Centauri, however.

    5. Re:The term you are looking for is "ablation" by Daetrin · · Score: 3, Informative
      No, that's not the term that's being looked for, or at least not exactly. From the article itself:

      "Most obviously, how do you design a pusher plate that won't shake itself apart or ablate under repeated impacts of nuclear plasma? (answer: with a thin coat of oil, reapplied between each atomic pulse.)"

      So the ship itself isn't really undergoing any ablation. I'm not sure if the term could be properly applied to a continuously resupplied coat of oil.

      --
      This Space Intentionally Left Blank
    6. Re:The term you are looking for is "ablation" by jcast · · Score: 1

      Steel is just carbon + iron ore, right? So you can get steel anywhere you have carbon and iron.

      --
      There are reasons why democracy does not work nearly as well as capitalism.
      -- David D. Friedman
  16. The Nuclear Salt Water Rocket by XNormal · · Score: 5, Interesting

    This is a design by Robert Zubrin for a rocket that produces a continous atomic blast using water with a high concentration of Uranium or Plutonium salts.

    Nuke Your Way to the Stars

    --
    Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.
    1. Re:The Nuclear Salt Water Rocket by Chris+Y+Taylor · · Score: 2

      The article at washington.edu about Zubrin's nuke designs says:

      "He has used a simplified model to show that the distribution of fission-inducing thermal neutrons in the reaction chamber depends critically on the velocity of the liquid fuel as it passes through the reaction chamber. This dependence occurs because the moving salt water fuel is also the medium in which the neutrons are slowed. If the liquid is at rest, the maximum flux occurs at the center of the cylinder, but if the moderating fuel liquid is in motion, the point of maximum flux is skewed downstream and also rises to a much higher maximum. If the right fuel velocity is chosen, the thermal neutron flux (and therefore the site of maximum fission energy release) can be made to peak very sharply just outside the exit end of the cylindrical reaction chamber."

      That is true only when the system is operating at a steady state condition. This means that, as with liquid fuel rockets, starting and shutting down the engine is going to be a difficult trick. It might be accomplished using a chemical shim to inhibit the nuclear reaction duirng startup and shutdown, but that is probably the sort of thing that would need experimental testing to prove (I don't trust computer models quite that much).

      Chris Y Taylor

  17. Warp drive when? by little1973 · · Score: 5, Informative

    You can find more info about advanced propulsion techniques (like the Orion-project) and other interesting space-science stuff at Warp Drive When?.

    --
    Government cannot make man richer, but it can make him poorer. - Ludwig von Mises
  18. We have nuclear submarines/carriers, why not ? by qurob · · Score: 1


    Those things go 25 years without needing to be refilled, or whatever.

    1. Re:We have nuclear submarines/carriers, why not ? by RobertNotBob · · Score: 1
      They also turn a propeller as a means to go for place to place. And then there's the 30 knots (unclassified) top speed.

      Hmmmm, propeller driven spacecraft... Neat idea you have there. All we have to do is find a intersteller river.

      --
      ___ I don't respond to Anonymous Cowards, and I Never Mod them UP.
  19. fission blowtorch by Anonymous Coward · · Score: 1, Interesting

    Dissolved uranium salts in water ejected by a magnetohydrodynamic drive (think linear accelerator for saltwater) with a neutron emitter to initiate fission at the egress point: that's the way to go. Any comments?

    1. Re:fission blowtorch by GuyMannDude · · Score: 1

      Dissolved uranium salts in water ejected by a magnetohydrodynamic drive (think linear accelerator for saltwater) with a neutron emitter to initiate fission at the egress point: that's the way to go. Any comments?

      Hey Einstein: write a scientific paper detailing your design and submit it to a scientific peer-reviewed journal. Then I'm sure you'll get plenty of comments (chuckle)!

      GMD

    2. Re:fission blowtorch by 0111+1110 · · Score: 1

      This wouldn't solve the starship problem. Water is heavy. You'd probably need more water than in all of Earths oceans to get to the Alpha Centauri system.

      --
      Quite an experience to live in fear, isn't it? That's what it is to be a slave.
  20. Bah we have Anti-Matter, why bother by kenp2002 · · Score: 0, Offtopic

    Hope out to particleadventure.com to read up real quick on the physics behind anti-matter. With an anti-matter drive, where the matter is anihalated into pure energy (momentarly) why both at this point dealing with nuclear? Yes I know AM is somewhat rare but jeez you think the leftist,socialist, posing as demoncrate fool tree-huggers are going to allow a nuclear drive?

    Anti-matter is pollution free (provided that the nightmare casacade scenario doesn't happen [Where an anti-matter matter interaction creates equal amounts of matter and anti-matter causing an eternal explosion, which as far as solid science is impossible...] it was from an old 70's comic book btw but some of those nuts in left, and the right, as both extremes have problems with reality actually quote from time to time fiction, versus reality. Reagardless I digress and apologize. Regardless of propulsion systems there is still a problem that MUST BE RESOLVED before we worry about propulsion. Regardless of if we can get there (whereever there is) we must resolve the sustainable habitiate issues (food and what not) gravity fatigue (time to go find the ever absent graviton so we can create non-spin artifical gravity), and physical atriculation (current space suits are not suited for extended phsyical activities, we need low profile exoskeleton systems, mmmm ACK! GUYVER!! Errr what was I talking about (Why was there a scottish guard in the guyver anime in TOKYO?) Again I digress it's time to end this post ACk... gurgle.... Et tu, Brute? ... Gasp! ... couch... hack.... weeze....

    -Later that night at the academy awards-

    Me- Thank you all and thank you to slashdot for giving me the opportunity to win the award for "Best Death in a /. Post" thank you all!

    --
    -=[ Who Is John Galt? ]=-
    1. Re:Bah we have Anti-Matter, why bother by Anonymous Coward · · Score: 0

      Dude, you need a breathalyzer attached to your computer.

  21. Ted Taylor also talked about Orion to John McPhee by Anonymous Coward · · Score: 0

    You can also read about Project Orion in John McPhee's book The Curve of Binding Energy . This book is mostly a long conversation between McPhee and Ted Taylor, (more) a physicist and ex- nuclear weopons engineer. In the early 70's Taylor becomes worried about how easy it is to build a fission bomb. Taylor and McPhee drive around and survey the security of nuclear materials while Taylor talks bomb theory and practice. The title comes from the curve on this page.

  22. Nukes for Nasa by Angus+McNitt · · Score: 5, Insightful

    The only question I would have about using Nuclear power for space launch woudl be not only be residual radiation at the launch site, but the weight of the craft itself. Too much weight and it won't lift, too little and you cook the occupants. Even a minimal craft woudl have to be very heavy. I would think re-entry would be very problematic. How do you retard you downward velocity enough not to destroy yourself landing. Make a blast chamber that stayed in space or burned up in atmosphere? Would be a great way to lauch heavy componants to a large space station thouhg.

    Also if you had an interuption in the blast progression, what would keep you from falling like the giant lead weight the craft would be? To use the Footfall reference again, wasn't that their major concern after the first one when off; keeping them going at the correct rate? Too little you fall, to fast and you either pulp your occupants or start to damage the "bomb guns". I guess now that part would be safer to test due to computer modeling. You wouldn't have to convert hundreds of tons of Nevada's sand into glass.

    Now, if you used it as a space based propulsion, that would be great. It would also help get rid of all those old Russian and American nukes that have been removed due to Anti-Balistic Missle treaties. Also any background radiation would disapate failry quickly.

    I'm not a physicist, so feel free to pick holes in this.

    --
    "To Do Is To Be" - Socrates, "To Be Is To Do" - Sartre, "Do Be Do Be Do" - Sinatra
  23. I concur and wish to add... by Howzer · · Score: 4, Interesting
    The Mars Society, in the process of encouraging and enabling manned missions to Mars, is currently doing this project among others.

    Cool hack if ever I have seen one! Build-your-own Mars Base in one of the most Mars-Like places on Earth, and do real research on how to operate said base when (not if) we get to Mars.

    If you keep up with the web traffic on this project, NASA's position seems to be basically "Great work guys!" and "Can we send our best people?" to which request the Mars Society seems to graciously and intelligently accede.

  24. Orion was never about efficiency by Bingo+Foo · · Score: 5, Interesting
    The Orion project was about getting to another star as fast as possible. Consider though, that "as fast as possible" means on a historic timescale, not merely short transit time. Given the technology we have (and had at the birth of Orion), making x BTU's worth of thermonuclear bombs and utilizing them at even 5% efficiency was a faster way to get a working craft to Sirius than trying to design an engine with controlled fusion.

    Keep in mind that all controlled, sustained nuclear reactions we have engineered to date are fission reactions. An inefficiently converted but uncontrolled fusion reaction (aka Hydrogen bomb) will still give more "bang for the buck," literally and figuratively.

    --
    taken! (by Davidleeroth) Thanks Bingo Foo!
    1. Re:Orion was never about efficiency by Anonymous Coward · · Score: 0

      Intermittent vs continous is the key here: for a few microseconds, you can design something to withstand the immense heat of a nuclear explosion, while designing a high-temperature reactor that runs continously is a bear. It's why diesels are more efficient than gas turbines -- you can't run a turbine at the same peak temperatures because it'll melt because of the continous exposure. The diesel mechanism, in contrast, has time to cool after combustion and expansion.

    2. Re:Orion was never about efficiency by Anonymous Coward · · Score: 0

      I agree that Orion wasn't about efficiency, but Orion was never about traveling to another star. It simply didn't have the power. Perhaps you are thinking of project Daedalus. But it was an excellent ship for traveling quickly to other planet. Their motto was "Saturn by 1970."

    3. Re:Orion was never about efficiency by Anonymous Coward · · Score: 0

      (Whoops!) I agree that Orion wasn't about efficiency, but Orion was never about traveling to another star. It simply didn't have the power. Perhaps you are thinking of project Daedalus. But it was an excellent ship for traveling quickly to other planet. Their motto was "Saturn by 1970."

  25. Project Thunderwell by ek_adam · · Score: 5, Informative

    It's been done. Short story, in the 1950's they were still testing nuclear weapons. They put one at the bottom of a long mine shaft and put a heavy metal plate on top to partially contain the explosion. The plate was last seen moving at about six times escape velocity.

    On the other hand, it probably vaporized before leaving the atmosphere, see Operation Plumbob for more information.

    1. Re:Project Thunderwell by grossinm · · Score: 2, Informative

      Check out project Gasbuggy as well. Small device was used to help extract natural gas from the ground. DOE Site here

    2. Re:Project Thunderwell by Anonymous Coward · · Score: 0

      I wonder how big a sewer explosion it would take to put a New York City manhole into orbit?

  26. Re: A Mote in God's Eye by RobertNotBob · · Score: 1
    While I enjoyed A Mote in God's Eye enough to finish it, you have to admit that the author is not looking for laurels to rest on when he writes; (not quoted directly)

    All of the best engineers come from the planet New Scotland, and most starship captains accept the notion that they intentionally speak with such a heavy accent that they are nearly unintelligable.

    I do not have enough of a memory to quote it directly, but that is almost it.

    --
    ___ I don't respond to Anonymous Cowards, and I Never Mod them UP.
  27. Oh, really? by fnj · · Score: 3, Interesting

    The air bursts (when the blast doesn't actually touch the ground) wouldn't have been that bad except for the initial EMP and radiation burst. Air bursts don't create fallout and are thus much cleaner then surface bursts (but I still wouldn't want to be around one).

    Oh, really? Hiroshima was an air burst (around 2000 feet; no crater was created). Are you really saying there was no fallout at Hiroshima? I know there is less fallout than there is with ground bursts, but none?

    1. Re:Oh, really? by RocketJeff · · Score: 2, Interesting
      Fallout is caused by matter being caught-up in the nuclear fireball.

      Air bursts create some fallout, but very little. In this case it's only the air/dust/smoke that's already in the air (or kicked up into the fireball by the blast).

      Hiroshima was actually a very clean explosion (for the time). Notice that most of the deaths from Hiroshima (even those from cancer today) are caused from exposure to the initial explosion, not from being in the area afterwards. If there was significant fallout, Hiroshima wouldn't have been habitible for quite a while (months at least) afterwards.

    2. Re:Oh, really? by Winterblink · · Score: 1

      I guess the point is that either a) they would build it in orbit and deorbit there, or b) they wouldn't boost away above a major urban center. :)

      --
      "I'm a leaf on the wind. Watch how I soar."
      -Hoban Washburn
    3. Re:Oh, really? by Anonymous Coward · · Score: 0

      I always liked that in Footfall, they launch that sucker in Mr. Bill's back yard. It just gives me a warm, fuzzy feeling to think about that.

    4. Re:Oh, really? by mesocyclone · · Score: 3, Interesting

      Yes. There was NO fallout from Hiroshima - in the sense of local, deadly fallout. There was dispersed, low level worldwide fallout.

      All of the radiation deaths in Hiroshima were a result of what is called "prompt radiation." This is the radiation dose delivered in the first minute of a blast. It includes the immediate radiation released by the fission reaction, and exposure to radiation from the very short lived elements in the fireball before they rise high enough and decay enough that the radiation flux is negligible.

      I say aain. There was NO localized fallout from Hiroshima. In fact, the first time fallout was recognized as a serious problem was after a south pacific test, when fallout, in the form of white flakes falling from the sky, fell on people outdoors on a relatively nearby island. They reported skin burns from the fallout, but there were no significant injuries.

      Ground bursts produce fallout because the radioactive elements (which are all vapor after the blast) are mixed with large amounts of particulate matter, condense on it, and fall from the sky from ground zero outwards downwind.

      Note also that there is controversy over whether low levels of radiation, such as what you get with distributed world-wide fallout (from stratsopheric transport of long lived radioactive elements from a fireball), is even harmful. There is little evidence that low doses are harmful, and there is some evidence that they are not (for example, on a county by county basis in the US, lung cancer rates are INVERSELY proportional to household radon levels). Almost all radiation dosage standards (such as the EPA 4picoCuries/liter - or is it m^2... oh well) are a result of extreme extrapolation from high dosage exposures. BTW... the same is also true of some toxic chemicals, although most toxic chemical recommendations come from extrapolating downward from lethal-dose 50% levels in animals - an even more fragile exercise.

      --

      The only good weather is bad weather.

    5. Re:Oh, really? by captn+ecks · · Score: 1

      Good one! If the moderators had read Footfall (by Niven & Pournelle) it would of at least reated 'Funny.' That launch scene was the emotional equivalent of 'D-Day' in terms to the novel. Very cool.

  28. Ted Taylor and THE CURVE OF BINDING ENERGY by Lumpish+Scholar · · Score: 5, Informative

    For more on Ted Taylor -- his work on fission bombs, his participation in Project Orion, his speculations on how small a nuclear bomb could topple the World Trade Center towers (decades ago), and his concerns about nuclear proliferation -- I strongly recommend John McPhee's The Curve of Binding Energy (BN). McPhee (BN) is an excellent writer, and this is one of his books I enjoyed the most.

    --
    Stupid job ads, weird spam, occasional insight at
    1. Re:Ted Taylor and THE CURVE OF BINDING ENERGY by Anonymous Coward · · Score: 0

      I couldn't agree more. I was addicted to this book
      from the moment I started reading it. I think it offers a fascinating account of the practical uses nuclear energy designed by some of the physicists in the 40's, 50's, and 60's, as well as ethical issues and safeguarding. There is also a wonderfull transcript of a presentation by Ted Taylor at
      http://www.sondra.net/concerns/ttspeech.htm.

  29. Good interview with the Dysons about Project Orion by jimkski · · Score: 4, Informative
    NPR's TOTN Science Friday broadcast an interview with Freeman and George Dyson a month or two ago. You can hear the interview at the NPR Archives:

    http://search.npr.org/cf/cmn/segment_display.cfm?s egID=145345

    The interview is great for conveying the commitment and enthusiasm Freeman felt for the Orion Project. They really believed that the ship would be build and flown to Mars last century. With NASA's new administrator Sean O'Keefe talking about alternative propulsion systems (including nuclear), who knows maybe Dyson's ideas will actually see the light of day.

    --
    yea i stole your sig- whats the big deal, it sucked anyway.
  30. Not intended for launch by elh102 · · Score: 2, Informative

    "It seems ludicrous to imagine that a spaceship could ascend into orbit and beyond by riding the impulses produced by a series of external atomic explosions...."

    That's because it IS ludicrous, at least the "ascend into orbit" part. It has been a while since I read anything about Project Orion, but I'm pretty confident that this propulsion technique was intended for use only in space. The spacecraft would most likely have been assembled in orbit, or possibly launched from Earth by one mother of a big chemical rocket.
    1. Re:Not intended for launch by sphealey · · Score: 4, Informative
      That's because it IS ludicrous, at least the "ascend into orbit" part. It has been a while since I read anything about Project Orion, but I'm pretty confident that this propulsion technique was intended for use only in space. The spacecraft would most likely have been assembled in orbit, or possibly launched from Earth by one mother of a big chemical rocket.
      Interestingly, that turns out not to be the case.

      First, the starting point of Orion was asking the question, "How do we get multi-ton payloads into space?". Chemical rockets, then and today, take tremendous amounts of resources to get a few hundred kg into space. Then and now, that doesn't really do much for anyone.

      Second, you have to remember that the Orion project started during the era of above-ground nuclear testing. Yes, an Orion launch would have created some fallout and upper-atmosphere contamination. But compared to the 10 MT (US) and 60 MT (USSR) monsters that were being fired for test purposes, the pollution wouldn't have seemed so bad.

      Of course, times have changed, and I doubt anything like this will be ever be used in the atmosphere except in dire circumstances (Footfall, Deep Impact).

      sPh

    2. Re:Not intended for launch by Phurd+Phlegm · · Score: 1
      That's because it IS ludicrous, at least the "ascend into orbit" part. It has been a while since I read anything about Project Orion, but I'm pretty confident that this propulsion technique was intended for use only in space. The spacecraft would most likely have been assembled in orbit, or possibly launched from Earth by one mother of a big chemical rocket.


      Another person that should read the book. The intent was most assuredly to launch from the ground. Later in the program there were some proposals to use chemical launch, but there were some pretty big economies to be had with larger vessels that were ground-launched. One interesting passage discusses the fact that in the Cold War times, the tradeoff that ten a hundred people might die from cancer (spread evenly over the surface of the globe) was considered an acceptable trade for launching a 4,000 ton ship that could go to Mars or Jupiter.

      I'm not so sure it isn't a good tradeoff, when you look at the hidden costs of coal-fired power plants (and probably solar cells, biodiesel,...).

    3. Re:Not intended for launch by Anonymous Coward · · Score: 0

      that turns out not to be the case


      Obligatory Rennerism...
    4. Re:Not intended for launch by Beryllium+Sphere(tm) · · Score: 1

      >Of course, times have changed, and I doubt anything like this will be ever be used in the atmosphere except in dire circumstances

      Dire circumstances, or by people who just don't care what anyone else thinks.

      Wouldn't it be interesting if North Korea went on an ego trip and went to Mars with their bombs? (Not that they have enough).

    5. Re:Not intended for launch by scharkalvin · · Score: 1

      Maybe someone should look up the details of project pluto. That was an atomic powered ram jet that would have powered a giant doomsday flying bomb. It would have been like a large supersonic V1 circling the globe dropping abombs everywhere.

    6. Re:Not intended for launch by Ranten_N_Raven · · Score: 1

      To see what it might look like, see a drawing of Archangel Michael, as envisioned by Niven & Pournelle, at

      http://www.up-ship.com/apr/michael.htm

      This thing is like a battleship -- built to take it and to REALLY dish it out.

      I'd go for a ride!

      --

      READ the US Constitution, the Bill of Rights and the other amendments! http://lcweb2.loc.gov/const/const.html
  31. No Nukes! by mustangdavis · · Score: 1

    First, like many people here, I don't understand how a nuclear explosion won't destroy the ship it is trying to move through Space at "warp speed". This seems pretty dangerous to me. Good luck finding anyone to fly that thing!

    Second, haven't scientists just discovered how to have the same piece of matter in two locations at one time? In theory, this means that we might be able to "beam" things, rather than blow them up while trying to move them.

    I seriously think we need to consider non-tradional methods of relocating ourselves rather than blowing ourselves up.

    Besides, what would happen if a large nuclear powered space craft had a mishap and crashed into the earth? (or Mars??) ... do we really want to destroy the places we are trying to explore?

    C'mon karma points!!

    1. Re:No Nukes! by Anonymous Coward · · Score: 0

      Most small nuclear explosions don't even destroy solid things more than a few klicks away. Sure, they buffet them with hot winds and irradiate them, but leave them standing. The bomb in an orion is exploded some distance from the "pusher plate" hemisphere, anyway.

    2. Re:No Nukes! by crosbie · · Score: 1
      I think scientists have discovered how to duplicate a particle, but it's a while before we get to replicating a complex structure.

      Probably the best way of doing space travel is to transport information rather than matter, i.e. use robots under remote control rather than send people out there.

      There's a latency problem, but I reckon that'll get solved before we solve the escape velocity problem. Although the space elevator is pretty neat.

      Here's an article I wrote almost a decade ago:

      'Interstellar Travel' is an Oxymoron

    3. Re:No Nukes! by Gilmoure · · Score: 2, Informative

      While a nuclear explosion is rather devastating, it doesn't totally vaporize everything. H bomb tests at Bikini atoll included Navy ships so we could see how they weathered the explosion. I think there's a picture with one cruiser lifted hundreds of feet up in the air with one of these tests.

      For an Orion, you build a really thick plate (it will slowly wear away) with some ablative surface (carbon, oil?) and set off the nuke some distance from it. You don't capture all the force of the explosion but what you do bumps you along.

      --
      I drank what? -- Socrates
    4. Re:No Nukes! by sphealey · · Score: 4, Informative
      While a nuclear explosion is rather devastating, it doesn't totally vaporize everything. H bomb tests at Bikini atoll included Navy ships so we could see how they weathered the explosion. I think there's a picture with one cruiser lifted hundreds of feet up in the air with one of these tests.
      The original "Bikini" test that you refer to was a shot of a 20 kt fission weapon - essentially the same as the one used at Hiroshima. The first test of a fusion weapon, the "Mike" shot, ended up being a bit larger than predicted at 10 MT. It vaporized an entire island about 2 km in diameter to a depth of about 100 m! That's a lot of vaporized rock.

      sPh

    5. Re:No Nukes! by autopr0n · · Score: 2

      First, like many people here, I don't understand how a nuclear explosion won't destroy the ship it is trying to move through Space at "warp speed". This seems pretty dangerous to me. Good luck finding anyone to fly that thing!

      That's because you're stupid, not because it isn't possible.

      --
      autopr0n is like, down and stuff.
    6. Re:No Nukes! by nusuth · · Score: 1

      I hope you learned instaneous information travel means time travel, which makes all "speed" issues irrelevant, during the decade.

      --

      Gentlemen, you can't fight in here, this is the War Room!

    7. Re:No Nukes! by crosbie · · Score: 1
      I have heard that argument, but I remain unconvinced.

      Here's a thread of a conversation I had on that subject: www.lns.cornell.edu/spr/1999-07/msg0017259.html

  32. Hrmmm, I wonder by splume · · Score: 1

    if the Rocket Guy would be interested in something like this?

    --

    Who is John Galt?
  33. Side note: Esther Dyson. by autopr0n · · Score: 4, Funny

    I remember reading an interview with Freeman Dyson a couple years ago in wired. He mentioned a week he visited his Daughter, Esther, at Harvard. During the time, she never attended a single class.

    When he asked her about it, she said something like "you don't go to Harvard to study, you go to meet people."

    It's interesting that she was one of the fist heads of ICANN.

    --
    autopr0n is like, down and stuff.
  34. The Curve of Binding Energy by Zergwyn · · Score: 3, Interesting

    This is one of the books you should read if you are interested in research, both with weapons and peaceful purposes, that was done with nuclear weapons. Theodore B. Taylor was one of the most interesting and ingeninous nuclear researchers ever, and had many ideas for using directed charge nuclear devices for everything from rockets to digging subways that would span the entire continent. He also discusses how easily nuclear devices can be made, and a lot of the current state-of-the-art in devices. A definite good read. More info about the book can be found on amazon here.

  35. Metroid? by Ill_Omen · · Score: 1

    I hope I'm not the only one reminded of Metroid and the bomb-climbing trick.

  36. Dyson Sphere by Anonymous Coward · · Score: 1, Informative

    Remember the 'Dyson Sphere' episode of ST:TNG where Scotty had been trapped in a regenerative transporter cycle for 75 years in his ship, stuck on the sphere?

    Well, Freeman Dyson is that Dyson.

    See the Dyson Sphere FAQ for details.

    1. Re:Dyson Sphere by Anonymous Coward · · Score: 0

      DUH!

      Jeebus, this isn't CNN!

    2. Re:Dyson Sphere by Anonymous Coward · · Score: 0

      And ST:TNG is supposed to lend some sort of credibility here?

  37. Orion vs NERVA vs VASIMIR by Latent+Heat · · Score: 4, Interesting

    Way I see it there are three approaches to nuclear propulsion: 1) Orion -- putty-putty bang-bang, 2) NERVA -- high power density reactor which heats up hydrogen that squirts out a conventional rocket nozzle, and 3) VASIMIR (Variable specific impulse magnetic rocket) -- use the nuclear reactor for an electric power station and accelerate hydrogen or other gas with a magnetic rocket nozzle (there is also ion drive, but VASIMIR is popular these days because it offers the greatest thrust of all the electric schemes). The book, in talking the politics, indicated that NASA Huntsville though that Orion was pie-in-the-sky before doing something like NERVA first. VASIMIR is a more recent proposal and was not under consideration in that era. My understanding is that NERVA would be a replacement 3rd stage to a Saturn V -- that way the reactor would not be turned on until you got into space. One thing about NERVA is that its propellant is stores as liquid hydrogen, which is one of the bulkiest, least dense liquids around. The NERVA stage would have been huge, essentially the same diameter as the S-IC and S-II rocket stages below it, making the nuclear Saturn V one continuous cylinder until you got to the payload fairing. Given the weight of the reactor and given the bulk of the hydrogen tank, I am wondering if the 800-second specific impulse compared to the 430-second specific impulse of the regular Saturn S-IVB upper stage would have been a wash. Orion had a bulk problem too. If it was ground launched, if could have had a much bigger diameter pusher plate to capture more of the nuclear explosion and be more efficient (or perhaps less inefficient). Its efficiency came from the ultra-high temps of a nuclear blast compared to a sustained nuclear reactor and its inefficiency came from most of that efficiency being wasted apart from the little bit captured by the pusher plate, and the bigger the pusher plate the better. I thought they said a ground launch Orion could be in the 10000-second specific impulse range while the Orion launched as a third stage of a Saturn V was reduced to about 2000-second specific impulse because of the smaller pusher plate -- you start getting into the is it worth the bother range. I actually think that the Orion approach would be by far the easiest from the engineering standpoint, given how much work and testing went into bomb making. The only holdup is the idea of polluting even space let alone the Earth with that much fission fragments.

    1. Re:Orion vs NERVA vs VASIMIR by WolfWithoutAClause · · Score: 2
      "but VASIMIR is popular these days because it offers the greatest thrust of all the electric schemes"

      Ahem. Actually, it gives less thrust than most ion drives per kilowatt, noteably Hall effect thrusters.

      Part of the problem is energy- for a given megawatt of power, with VASIMR most of it ends up in the extremely high velocity exhaust (5400 seconds == 54000 m/s) where you don't want it, rather than the vehicle, which you do.

      There's a theorem that says that if you keep your ISP constant there is an optimum exhaust velocity for minimum energy- it's about 2/3 of the mission delta-v. To get to mars you need a delta-v of about 5 km/s not 54km/s. The reason minimum energy is important is because nuclear reactors are not noted for having a light weight- there's no point saving fuel at the cost of extra overall weight.

      Of course VASIMR varies its ISP, which helps, but it goes from very-high, to way-too-high ;-)

      --

      -WolfWithoutAClause

      "Gravity is only a theory, not a fact!"
  38. Artificial Gravity by IMarvinTPA · · Score: 2, Interesting

    If we were to develop a ship that accelerated at 9.8 m*m for the first half of a trip, and then slowed at the same rate for the second half of a trip, would that be sufficient for artificial gravity?

    Andy

    1. Re:Artificial Gravity by Genyin · · Score: 1

      yes.

      Now come up with a way to get that type of thrust constantly...

    2. Re:Artificial Gravity by Anonymous Coward · · Score: 0

      Yes, absolutely. It's already been discussed many times in science fiction stories. Accelerate out at one G for time T, then weightless for a brief period during "turn around", then decelerate at one G for time T at which time you are where you were going to.

    3. Re:Artificial Gravity by crosbie · · Score: 1

      Work out approximately how many AU away you'd be now, if you'd been born on a spaceship in Earth's orbit just as it resumed 1g for a trip to the stars....

      Alternatively, how old would you be if the trip was to Proxima Centuri?

    4. Re:Artificial Gravity by Anonymous Coward · · Score: 0

      Simple according the the formula d=.5*g*t^2, the calculus give t=sqrt(2*d/g) with d=4 light years, g=9.8m/s^-2

      It will take less than 2 years and 288 days (or 10 months).

    5. Re:Artificial Gravity by crosbie · · Score: 1

      Thank you Isaac Newton!

      Perhaps some budding Albert Einsteins out there would like to provide a better answer?

    6. Re:Artificial Gravity by Pig+Hogger · · Score: 2
      If we were to develop a ship that accelerated at 9.8 m*m for the first half of a trip, and then slowed at the same rate for the second half of a trip, would that be sufficient for artificial gravity?
      Read Georges Rémi's (Hergé) Objectif Lune ( Destination Moon ) and On a marché sur la Lune (Explorers on the Moon ) comic books for an excellent story on the design, building and use of an atomic-powered rocket to the moon (and back - including an attempt at spacejacking) which provides artificial gravity through continuous 1G acceleration.

      The fact that it was written 50 years ago in Belgium does not remove much of it's scientific accurary.

    7. Re:Artificial Gravity by IMarvinTPA · · Score: 1

      I take it you intend to stop the fast and hard way? (BAM!)

      Shouldn't you calculate how long it would take you to get half way and then double it if you intend to stop the same way you sped up?

      Andy

  39. Crazier than Orion by Latent+Heat · · Score: 2, Interesting
    Zubrin had a crazier idea than Orion -- the nuclear salt water rocket.

    The idea is that you would have a tank of water with uranium salt in solution along with enough boron so the thing would go off at once. You piped this salt water into a reactor chamber where you somehow extracted the boron so that you would get a nuclear chain reaction inside the chamber and then the super heated salt water would squirt out the back.

    As somewhat less crazy idea is that you would entrain uranium hexafluoride gas in a vortex in a reactor and pump hydrogen through it -- kind of a look-Ma-no-walls version of NERVA.

    1. Re:Crazier than Orion by Anonymous Coward · · Score: 0

      "As somewhat less crazy idea is that you would entrain uranium hexafluoride gas in a vortex in a reactor and pump hydrogen through it -- kind of a look-Ma-no-walls version of NERVA. "

      It's an extremely cool concept (certainly not unique to Zubrin) called a gas-core reactor. It was first thought up in early '60's when boffins working on nuclear rocket engines kept finding the limit on the engine efficiency was the heat the reactor could stand without melting. Which led to the neat idea of "Why does a reactor have to be solid anyway?".

      So the idea is quite old. However, like a lot of neat ideas of that era (eg scramjets) it was impractical to work on until there was enough computing power to properly simulate it due to obvious difficulties in setting up a test.

      Basically it requires some truly awesome CFD (Computational Fluid Dynamics) work to see if it is practical and in particular whether the vortex can be made stable. Then there's the political, er, fallout if anyone wants to go ahead with it.

      But at the moment it appears to be the best bet for near-term very high-power rocketry (fusion and anti-matter catalysation still being even more theoretical). With no structural upper limit on the reactor temperature the specific impulse could be colossal.

      For info on it (and other nuclear rocket engines) see http://www.lascruces.com/~mrpbar/rocket.html, which includes a link to an early paper on the subject.

      "I'm the urban spaceman, baby..."

  40. Aliens plan revenge for steel plate destroying... by Kristoffor · · Score: 2, Funny

    planet. AT 3:am GMT today the governments of most of the nations of earth received a formal declaration of war from an alien race who claims we fired the first shot. After many hours of discussion it was determined that this "first shot" was a large steel plate intended to dampen the effects of a nuclear explosion test performed by the United States many years ago. The steel plate propelled by the explosion escaped the earth's gravity at a heading that led it on a collision course with an unsuspecting race of aliens, almost wiping them out to the last being. The American government has made plans to compensate the few surviving members of the afflicted race by granting them naturalized citizen status and homes in Los Angeles where their outer worldly looks and nature is unlikely to be noticed.

  41. Shaped Nuclear Explosions by Salgak1 · · Score: 1
    I recall an article in Scientific American in the early 1980s that was talking about "shaped" nuclear explosions. Unfortunately, their online archive only goes back to 1993, and this was 1982-83 as I recall. . . .so no reference. Sorry.

    However, it seems logical that by shaping the initial portions of an nuclear explosion, just as you would with conventional explosives, you should be able to achieve SOME degree of directional channelling of the energies. Mind you, what I know of nuclear weapons design can be written in VERY large letters on a VERY small piece of paper. . . but as I recall, the SciAm article made it seem plausible, even suggested engineering uses for shaped nukes. . ..

  42. Now there's a techie's dream! by Salad+Shooter · · Score: 0

    Traveling through space on the fireballs of nuclear explosions! Unfortunately, the book spends much more time on politics than on physics or engineering. Still, I suppose you've got to be quite a political animal to get money for this sort of thing.
    Dyson excuses the lack of technical data by noting that much Orion information is still secret (like how to make a nuclear bomb with a golf ball-sized chunk of plutonium), but the deficit still cries out. There's just enough technical material to make you wish for more. Virtually all the graphics seem to be multi-generational copies of just a few original project drawings. There were no significant original graphics.
    The character sketches and descriptions of fighting for funds are well done and tell us a lot about how government really works (slowly, wastefully, and on an old-boy network), but "The True Story of the Atomic Spaceship" is not an accurate title for this book.
    I sold the book immediately on finishing it.

  43. GA by Anonymous Coward · · Score: 0
    I always thought General Atomics was the coolest name for a company.

    I once worked for a researcher who had done some time at GA. He had some crazy ideas for research projects. I vowed that I would never be in the same building as the experiment when it finally got running. And, when it caught on fire, I was not going to be in there in my asbestos suit shoveling burning liquid sodium; I was going to be looking for a new job.

  44. Re:Footfall a classic? -- because of Orion by Anonymous Coward · · Score: 0


    Actually it was the Orion launch description which almost alone made Footfall worth the read (though I agree many scenes and characters, especially Harry were remixes of LH). "~ An atom bomb went off under Harry's ass... ~".

  45. A Family of Incredible Minds by merger · · Score: 5, Interesting

    Just briefly I had the opportunity to meet George Dyson (a really nice down to earth guy). If the name sounds at all familiar, his sister is Ester Dyson (used to be chairperson of ICANN) and father is Freeman Dyson (a well known theoretical physicist). From what I've heard, George was always the odd one out in the family taking his own path. He used to live in a great looking tree house on the north end of Vancouver Island and then went on to research and build baidarkas (an Aleut Kayak).He has a great book on the kayaks called "Baidarka" which in the first half covers the history of the their development and Aleuts interaction with Russian traders and then moves on to cover the vessels themselves and his work.

    He then went on to research and write a book on A.I. titled "Darwin Among the Machines: The Evolution of Global Intelligence". In addition to the original theories about using nuclear explosions to propel space ships, his father had the concept of building a huge structure around a star that people would live on the inside of and the star would provide the energy. You may remember this from a Star Trek Next Generation where they brought back Scotty, it was the Dyson Sphere. A final interesting tidbit is that George Dyson's grandfather Sir George Dyson was an English composer and founder of the National Federation of Music Societies.

    Overall, it's an interesting family with some incredible minds in it. The BBC has a short piece on his AI book and on the left hand column is a real audio interview with George. There are also plenty of other links on google if you plug in his name.

    1. Re:A Family of Incredible Minds by Nutrimentia · · Score: 1

      I've met a George a couple times and concur on the opinion that he's a real down to earth guy. Willing to endure talking to me from time to time as well; his generosity knows no bounds!

      Egde.org has a presentation made by George about the book Darwin among the machines here:

      http://www.edge.org/3rd_culture/dyson/dyson_p1.h tm l

      All 4 books mentioned here (Project Orion, Baidarka, Starship and Canoe, and DatM) are enjoyable and thought provoking.

  46. A good related book by phr2 · · Score: 3, Interesting

    is "The Starship and the Canoe" by Kenneth Brower. It's actually about Freeman Dyson (the "starship" refers to the Orion project) and George Dyson (who at the time was living in the Alaska wilderness). It's not really a techie book about specific impulses or engineering history, but a good read about these two very interesting people.

  47. The elder Dyson's books by StefanJ · · Score: 3, Informative
    Project Orion is in the honored last position of my read-me stack. I save the most interesting stuff for last.

    I feel compelled to plug Freeman Dyson's semi-autobiographical Disturbing the Universe:

    http://www.amazon.com/exec/obidos/ASIN/0465016774/

    I like the very earliest review. Mine's the one after.

    Dyson's books are as interesting as science fiction, but without the cranky politics and cluelessness about the human condition that pervades much of the genre. Imagined Worlds is a sort of lite version of Disturbing the Universe; Weapons and Hope is a still-relevant book about arms control from the mid eighties.

    1. Re:The elder Dyson's books by geekoid · · Score: 2

      "Project Orion is in the honored last position of my read-me stack. I save the most interesting stuff for last."

      So, after you die you can look back and say "Man, there was a lot of interesting stuff I was going to read"?

      Personal, I read the interestng stuff first, then after I die I can say "look at all the unintersting stuff I didn't have to read, WOOT!"

      OTOH I can't understand why someone would read something they don't find interesting, unless mandated by a high force, such as school.

      --
      The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
  48. Hangliders by docbrown42 · · Score: 1

    Dont forget the hangliders.

    -Ed

    docbrown.net NEW!
    Graphic Design, Web Design, Role-Playing Games...all the good stuff

    --
    Ed Wedig
    Graphic design services
    docbrown.net
  49. The Binding Curve Of Energy by ronaldcromwell · · Score: 2, Informative

    A book by John A. McPhee, written in 1979, called The Curve Of Binding Energy gives an excellent account of this project, including an inverview with one of it's cheif designers. It's a fabulous book, and it's short, so you could read it in a night (a long night, but hey :>) Check it out at borders.

  50. Another book that discusses Orion by Anonymous Coward · · Score: 0

    From none other than the man that dreamed it all up:

    "Disturbing the Universe" By Freeman Dyson

    It's a wonderful book that adds a human element to the early years of the cold war.
    -johnny

  51. Re:Side note: Esther Dyson. by Anonymous Coward · · Score: 0

    You just described the whole reason for the tech bubble.

    People like her. And that guy who published the "Whole Earth Catalog". I think he started some flashy magazine where he hyped the new "digital economy" where "all the old rules don't apply".


    gotcher nose!

  52. footfall: by Unknown+Poltroon · · Score: 1

    Actually, they were worried about the second bomb going off. If the first one fails, no problem, but if the second one fails, your high enough to cause major damage if you fall. Presumeably by the time the third one goes off, youve got a little more time to allow for mechanical difficulties.

    --
    All Troll + "offtopic" mods are meta moderated as "Unfair", because you abused the system.
  53. Space travel isn't feasible by Animats · · Score: 2
    Space travel with chemical fuels isn't feasible.

    After half a century of building big rockets, we now know that they don't work very well. Half a century ago, they were use-once-and-throw-away devices, and they still are. Payloads are still tiny compared to the launch weight, even for the Shuttle. Compare the figures for jet aircraft, which can be half payload.

    Reliability is still lousy, too. This is because so much weight reduction is required just to get the things off the ground that they don't have adequate safety margins. About 10-20% of satellite launches still fail, almost half a century after the first one. That number isn't improving, either; in fact, it was a little better in the 1970s. There have only been a few hundred Shuttle flights, and it's blown up once. Commercial aircraft flights, by comparison, fail a few times per year, out of millions of flights.

    Half a century in aviation took us from the Wright Brothers Flyer to the B-52. Half a century in rocketry took us from the Atlas I to the Atlas V. There's been little progress in launch vehicles since the 1960s. All the major launch systems were created decades ago.

    So chemical fuels just don't have the power-to-weight ratio for useful space travel. People knew this in the Orion days; it's a straightforward calculation. It's unfortunate that an Orion wasn't launched once or twice, just to demonstrate that nuclear propulsion is possible.

    1. Re:Space travel isn't feasible by Caradoc · · Score: 3, Insightful

      SSTO (or Single Stage to Orbit) vehicles still use chemical fuels - they just use them more efficiently.

      I think we're going to see some progress in this field over the next few years, assuming that the American Taxpayers don't start squawking that the money for the space program would be better used to feed people who're too lazy to work.

      --
      Specialization is for insects. - R.A.H.
  54. Sort of! Re:Dyson Sphere by StefanJ · · Score: 2
    In the essay "Extraterrestrials," Dyson specifically denies having come up with the Dyson Sphere.

    He gives credit for the concept of a star-swaddling energy collector to a book he found in a London subway stop book stall: the quasi-novel Star Maker by SF writer and philosopher Olaf Stapledon:

    http://www.amazon.com/exec/obidos/tg/detail/-/0486 219623/

    Freeman Dyson is best known to SF fans because of the "Sphere" concept and the Orion drive. But please check out the guy's actual writing. There's a lot more to him than this eye-candy.

    1. Re:Sort of! Re:Dyson Sphere by DNS-and-BIND · · Score: 2
      The politically correct name should then be Stapledon Sphere, not Dyson Sphere.

      Don't tell me The Next Generation got its facts wrong, AND passed up an opportunity to be politically correct? It pushes the limits of believability, you understand.

      --
      Shutting down free speech with violence isn't fighting fascism. It IS fascism!
  55. Nitpick by roystgnr · · Score: 2

    Of course, times have changed, and I doubt anything like this will be ever be used in the atmosphere except in dire circumstances (Footfall, Deep Impact).

    They said in Deep Impact that the Orion ship was assembled in orbit (although it looked like a close enough orbit to create hell with EMP, at least).

    They also didn't talk about Orion propulsion at all, which was just horribly disappointing. Yes, it was a long movie, but couldn't they have spared 60 seconds to show us the astronaut's reactions to riding a nuclear arsenal? It could have been made part of the plot, too: "We've used up all our bombs that we tried to destroy the comet with, but we still have a ton of bombs that were intended to decelerate us when we returned to Earth..."

    1. Re:Nitpick by sphealey · · Score: 2
      They said in Deep Impact that the Orion ship was assembled in orbit (although it looked like a close enough orbit to create hell with EMP, at least).
      Sorry, I should worded my reference more carefully. I meant that if the Earth actually faced a real asteroid impact scenario with enough time to respond, as illustrated in the fictional movie Deep Impact, the inhabitents of Earth might be willing to eat the fallout from an Orion launch to avoid total destruction.

      sPh

    2. Re:Nitpick by Anonymous Coward · · Score: 0

      I'm sure Greenpeace would protest it in any event.

  56. Nuclear Propulsion in "2001" by bobl · · Score: 1

    Either in "The Making of 2001" (author unknown) or Arthur C. Clarke's "The Lost Worlds of 2001", it was mentioned that the (appropriately named) shuttle "Orion" that Heywood Floyd rode from the Space Station to the Moon was originally planned to be nuclear-powered.

    In the final script, Kubrick and Clarke dropped the idea, perhaps for the same reason they toned down other nuke references: too reminiscent of "Dr. Strangelove".

    1. Re:Nuclear Propulsion in "2001" by spitzak · · Score: 2

      I think that was the "Discovery", the ship going to Jupiter, that they considered making bomb-powered, and in the end certainly had some sort of nuclear engines. They tried to put the huge fins needed for heat dispersal onto it but they never looked good so they left them off in the movie.

      The shuttle was always intented to be chemical powered, I think, unless those are some sort of nuclear rockets.

  57. If We Build a Space Elevator by invid · · Score: 3

    and an atomic rocket then we'll be in business people! It will finally be here--we'll finally have an interplanetary civilization! This is what we need to aspire to. This is our destiny. Let's make it happen people. Go! Go! Go!

    --
    The Moore-Murphy Law: The number of things that will go wrong will double every 2 years.
  58. for real by fea · · Score: 1

    Here at ORNL, we still have what is left of a research project to investigate the feasibility of a nuclear-powered airplane; the idea being to fly around the earth for extended periods without refueling. There also is present research, some of which is done at ORNL, in the area of nuclear-powered space ships; in the nuclear world called "space reactors".

  59. Also on Sagan's Cosmos by GuyMannDude · · Score: 2

    One of the episodes of Carl Sagan's Cosmos series dealt with long distance space travel and showed examples of proposed starship design and the Orion was one of them. He, of course, had to insert one of his typical comments about how that would be a much better use for nuclear technology than bombs, but the episode is worth watching anyhow.

    It seems ludicrous to imagine that a spaceship could ascend into orbit and beyond by riding the impulses produced by a series of external atomic explosions.

    I wish that submitters would really refrain from inserting their own editorial comments and judgements in the stories they submit. Cosmos was aired over two decades ago. So the idea for Orion did not seem ludicrous to me. Couldn't this guy just comment on the book instead of making a guess as to how knowledgable the entire slashdot community is on starship design?

    GMD

    1. Re:Also on Sagan's Cosmos by Anonymous Coward · · Score: 0

      >I wish that submitters would really refrain from inserting their own
      >editorial comments and judgements in the stories they submit. Cosmos
      >was aired over two decades ago. So the idea for Orion did not seem
      >ludicrous to me. Couldn't this guy just comment on the book instead of
      >making a guess as to how knowledgable the entire slashdot community is
      >on starship design?
      >
      Are you a member of the Pournell/Niven fanclub? Orion *WAS* a ludicrous idea two decades ago. People like you bitch about the problems and downtime with the Shuttle? Imagine the problems and downtime with *THIS* baby! How the hell would you be able to effect any repairs at all on this thing? I sure as hell wouldn't be caught halfway bettween earth and the moon,mars or anywhere else when this thing has a "problem"

  60. Didn't we learn anthing from the Superman Movies by DCram · · Score: 1

    Ok..
    Lets look at the simple facts.

    Superman II:
    Superman stops a nuke by throwing it into space. then what happens you ask? Three more friggin flying people come down to earth and try to distroy it along with superman in a quest for world domination.

    Superman IV: The quest for peace
    Superman takes a bunch of nukes and throws them into the sun, BUT since there is some genitic tissue in the damn things it makes .. yup you guessed it.. another friggin flying dude bent on world domination. AND superman goes all evil!! Well I have another theory that "Little" Superman took over for a while so he could tag some fine ass!

    So let me stress here.. WE SHOULD NOT DETONATE NUKES IN SPACE!! unless we want to see more of the same.

    --
    If I were only smart enough to accomplish the things I dream about.. Or maybe too dumb to care.
  61. 'rare' is a bit weak... by autopr0n · · Score: 2

    Hope out to particleadventure.com to read up real quick on the physics behind anti-matter. With an anti-matter drive, where the matter is anihalated into pure energy (momentarly) why both at this point dealing with nuclear? Yes I know AM is somewhat rare but jeez you think the leftist,socialist, posing as demoncrate fool tree-huggers are going to allow a nuclear drive?

    Eventualy all of those afraid of nukes will die off. There's no rational reason to be afraid of them.

    Anyway, antimatter is a bit more then 'rare' a single atom of antihydrogen costs something like $100,000 to produce. A billion dolars gets you just ten thousand atoms worth. that's about 1.5*10^(-10) jouls of energy.

    In other words, not a lot. Even if it just cost $1 to produce a single hydrogen atom of antimater, it would require $7.2 billion to get as much energy as a watch battery. But it dosn't, it costs ~ $100,000.

    --
    autopr0n is like, down and stuff.
    1. Re:'rare' is a bit weak... by Anonymous Coward · · Score: 0

      Not only is it too expensive it's also too clean. most matter/anti-matter reactions produce pure gamma rays, bot any rapidly moving particles or "thrust".

  62. Re: human costs by Anonymous Coward · · Score: 0

    Dyson estimated that about ten people would die from atomic contamination for every Orion launch.

    10 deaths per launch: collateral damage

  63. Nuclear -powered bomber by john82 · · Score: 1

    Under the NEPA (Nuclear Energy for the Propulsion of Aircraft) Project, the US Air Force had a contract with Fairchild to develop a nuclear-powered bomber. Part of the problem was that the project was split in two: the Atomic Energy Commission (AEC) was responsible for the reactor, and Fairchild/USAF was responsible for everything else (including a converted Convair B-36H).

    Well, that wasn't really the biggest problem. There was the small detail: where do you crash-land a nuclear-powered bomber?

    Class? The answer is: you don't.

    There's a good write-up available about Project NEPA.

    1. Re:Nuclear -powered bomber by Anonymous Coward · · Score: 0

      There was the small detail: where do you crash-land a nuclear-powered bomber?

      On enemy soil, of course. You do have an enemy, right? We're not just building nuclear-powered nuclear-armed strategic bombers as a public works project, yes?

      And, of course, if you can't arrange to have the bomber flying within crash-glide distance of hostile borders when the pooch gets screwed, I guess the nearest ocean, third-world nation, or Canada will have to do.

  64. Re:Side note: Esther Dyson. by Anonymous Coward · · Score: 0
    Freeman himself is very anti-educationist (Not against education, against educationism). He never got a PhD, but won a Nobel in Physics. He spoke at UI Urbana a few years ago and fielded several quesitons about education by basically saying that if you're interested and motivated, you will learn regardless of what some piece of paper says.

    I have to say that I only partially agree with him. I'm sure that if pressed he'd have to acknowledge the strong correleation between mastery of a field and granted degrees.

  65. Just like rocket-jumping? by t_allardyce · · Score: 2, Funny

    So basically, they want to propel a ship by blowing up nuke... Has someone been rocket-jumping in quake too much? or maybe thats grenade jumping... Either way, you end up getting damaged :)

    --
    This comment does not represent the views or opinions of the user.
    1. Re:Just like rocket-jumping? by jcast · · Score: 1

      Um, I reckon this project was started ~ 40 years before Quake was released?

      --
      There are reasons why democracy does not work nearly as well as capitalism.
      -- David D. Friedman
  66. Simple extra-solar space travel... by damien_kane · · Score: 1

    Since, with the current state of nuclear weapons, this would leave a lot of radiation at the lauch pad (and that would be a Bad(tm) thing), it pretty much puts it out of a terrestrial lauch.

    However, if we use a small rocket to get the craft up to a sufficient velocity, throw on a scramjet to lift it into orbit (i know i know, you need at least mach8 to leave the atmosphere, but we're still on the preliminay tests, right?).
    Then all we need to do is throw one of these Orion engines on the craft as well for propulsion in the vaccuum of space, and we're good to go, right?

  67. Buck Turgison by Anonymous Coward · · Score: 0

    I'm not saying we wouldn't get our hair mussed up.... but no more than ten to twenty million killed.... ah, depending on the breaks.

  68. Freeman Dyson by Pig+Hogger · · Score: 2
    Freeman Dyson (Freeman Dyson!) had no trouble believing in Ringworld.

    Introduction to The Ringworld Engineers (Larry Niven)

  69. Reading Order Re:The elder Dyson's books by StefanJ · · Score: 2
    I recommend a lot of books to people; to maintain karma, I try to respect others' recommendations, and check out and buy books I might not normally read.

    Per my rule above, I try to read these "should reads" before I read the books I really look forward to.

    Generally, it works out. I've often surprised myself. The Immense Journey by Loren Eiseley was on my "should read" list, and it turned out to be a gas; a really deep and portenteous nature book.

    And then there's Understanding Comics. That was on my "should read" list too. I hated and despised most comic books, but enough people recommended McCloud's book that I thought I should give it a try. DAMN! What a book. I buy a lot of way freaky comics, now.

    Or: Marketing Mishaps. I found this slim paperback in a Goodwill store. It is literally a textbook; case studies on companies gone wrong. I thought it would be a good "medicine" read, for understanding why products and companies fail. It was a gas! Now I know why A.C. Gilbert, highly respected maker of Erector Sets and Chemistry Sets, is now longer around.

    Clear enough?

    Stefan

  70. Ion Propulsion by Ragnarock · · Score: 1

    Why don't they use a nuclear reactor and a bank of, say 10+ ion propulsion engines for thrust and away they go. Yes, you would need a way to create the electricity out of the reactor, but it could be done. Hell we do it on submarines...

    --
    "Reserve your right to think, for even to think wrongly is better than not to think at all," Hypatia
  71. Man - talk about spoilers... by Anonymous Coward · · Score: 0

    I re-read the end of Football on a semi-annual basis to get pumped up.

    I did not enjoy the whole book... The end made up for it though - it has a great payoff.

    The reporter gets what he deserves in this book - that almost never happens...

  72. Ion engines are better by Stuntmonkey · · Score: 1

    Orion is interesting history, but not particularly compelling technology as is. These days ion engines perform as well as the Orion specs. They are also much cleaner and have been successfully tested in space:

    Most significantly, the DS1 engine achieved a specific impulse of 3100 seconds, which is comparable to Orion specifications and much better than chemical rockets. (The specific impulse indicates how efficient an engine is at converting propellant mass into forward momentum.)

    The one thing that ion engines aren't good for is producing a lot of thrust, so in particular you could never launch yourself off the ground with one. Presumably the Orion technology also wouldn't be used for this purpose.

    1. Re:Ion engines are better by StefanJ · · Score: 2
      Actually, the early concept Orion ships WOULD be launched from the ground.

      As I recall, the Isp for the larger versions of Orion STARTED at 10,000 seconds.

      Ion drives are great for unmanned flights, but the low thrust is a problem. You spend a lot of time just building up to escape velocity. During this time your crew is exposed to cosmic rays, are consuming expendables, and perhaps going stir-crazy. (Space . . . MADnesss!)

      For this reason, higher thrust at a lower Isp can be preferable. The trip costs more in terms of reaction mass, but you get there faster.

  73. We should use Orion as a contingency by Chairboy · · Score: 3, Insightful

    I'd like to suggest the following: BUILD an Orion ship in the middle of the desert over a period of years. Whenever a big piece of military hardware is decommissioned, install it somewhere on this Orion ship. Sidewinders, old A-10 guns that fire depleted uranium, hell, even ICBMs.

    Why? Just in case.

    Let's say an asteroid or comet threatens civilization: You'd have a solution that, as messy as it would be, would at least be superior to millions of people getting killed.

    What if aliens threaten us? We'd have SOME sort of defense.

    What if some unforseeable natural disaster takes place in space and only a big old spaceship will solve it? I'd rather we be prepared then not.

    Store is unfueled, keep the nukes where they are now. This way, it's no real threat to anyone. Keep the warheads off the ICBMs it has onboard, all this stuff could be installed in a day or so, if we were properly motivated.

    Have schools and colleges build simple re-entry capsules that don't have to be super lightweight.

    Put one or two submarine reactors onboard along with a big resevoir of water. Like Niven-Pournelle's Archangel, you could use water for attitude control. For 'precision' maneuvering, you could fire off an ICBM (properly aligned, of course).

    This would be neat, and it could be done a LOT cheaper then when you use purpose built components.

    1. Re:We should use Orion as a contingency by Anonymous Coward · · Score: 0

      >What if aliens threaten us? We'd have SOME sort of defense.
      >
      >
      Yeah. They'll laugh themselves sick, then blow it out of the sky. (Hopefully with you on it)

    2. Re:We should use Orion as a contingency by toddhisattva · · Score: 1
      Whenever a big piece of military hardware is decommissioned, install it somewhere on this Orion ship. Sidewinders, old A-10 guns that fire depleted uranium,...



      Sidewinders are little bitty short-range missiles. If you want decom'd big AAM (SSM?), shop for Phoenix! Bring lots of money.



      Also, the best use of an old A-10 gun would be in a new A-10, but fat chance....

    3. Re:We should use Orion as a contingency by Chairboy · · Score: 2

      Sidewinders might be short range in atmosphere, but in space.... c'mon, don't people watch anime any more?

  74. LH & Footfall by DJK · · Score: 1

    I think I remember reading in the forward to LH that they *were* going to write about an invasion with the attackers bombarding us with asteroids (Footfall), but N&P were so taken by the idea of asteroid (or comet) impact, that they wrote LH instead.

    I guess that explains some of the scene/character similarities.

  75. Apocalyptic jet plane by Anonymous Coward · · Score: 0

    It could fly for years without refueling and it would set things on fire if it flew too close to the ground.

  76. My favorite part of the book..... by Catmeat · · Score: 1

    Is chapter 17, entitled Coca Cola. It seems that the system they designed that would store bombs en-masse and reliably deliver them to the detonation point was partially inspired by the mechanism used in Coca-Cola vending machines to handle bottles.

  77. Funny, but... by Anonymous Coward · · Score: 0

    The name and concept of the "Dyson Sphere" was well known in SciFi circles long before even the first two pilot episodes of ST were written.

    Freeman Dyson ackowledges that he didn't orginate the concept... it's just named after him because he popularized it.

  78. Just an expression no more by Anonymous Coward · · Score: 0

    And I always thought that "Nuke 'em to the moon" was just an expression.

  79. SSTO vehicles are vaporware by Animats · · Score: 2
    What SSTO vehicles? None exist.

    Remember Rotary Rocket, with their commercial SSTO vehicle They're dead. Just a little bit of weight growth in the engine, and the design became unable to make it to orbit.

    1. Re:SSTO vehicles are vaporware by Caradoc · · Score: 2

      I'd agree that with current materials, SSTO vehicles won't work.

      With harder ceramics, lighter composites, et cetera ad absurdum, they *will* be feasible.

      The problem is that research projects keep getting killed in favor of feeding the breeders.

      --
      Specialization is for insects. - R.A.H.
    2. Re:SSTO vehicles are vaporware by Animats · · Score: 2

      Weight reduction is tough when well over 90% of vehicle weight at launch is fuel and oxidizer. Almost all of the fuel is used to lift fuel.

    3. Re:SSTO vehicles are vaporware by Anonymous Coward · · Score: 0

      Come on

      > The problem is that research projects keep
      > getting killed in favor of feeding the breeders.

      In the US? the one western country that has the lowest, cheapest and nastiest social program?

      Do your research and point to the military instead. Are you sure you need these F22? I think a single one of these pays for all of medicare ten times over.

      Cheers.

  80. Re: human costs by Anonymous Coward · · Score: 0

    Raggh! Collateral damage! You want collateral damage!? I'll show you collateral damage!!

  81. Ob Star Trek Reference by DCMonkey · · Score: 1

    That's what fuel intermix ratios are about.

    --
    DCMonkey
  82. Nuclear Pulse Propulsion by GiftNice · · Score: 1

    I went to the AIAA Joint Propulsion Conference and Nuclear Propulsion in space is still alive and well. One of the ideas I remember is the idea to ignite a small complicated speck of nuclear fuel with anti-protons and compressing it with ion beams to make a small explosion that would propel the ship. I personally would believe that nuclear reactor powered plasma engine like the VASMIR engine would be the best. The field of study is soo great I just wish they would fund it more!

  83. Astrochicken? by Anonymous Coward · · Score: 0

    Isn't this the same guy who proposed the space exploration probe astrochicken? The Astrochicken would be part machine, part animal, using advanced bioengineering techniques. It would 'eat' ice and hydrocarbons as fuel and be able to reproduce itself, travelling from planet to planet to gather food. On its way, it could also send back scientific information to Earth about the places it visited.

  84. Re: vacuum energy, QM by guybarr · · Score: 2


    also, It is not so well known that Freeman Dyson, among his many other ideas, also suggested a device to store vacuum energy (Casimir Force) known (IIRC) as Dyson-Plates.

    His biggest contribution (AFAIK) is the Dyson Interaction picture of QM and QFT, on which Feynman diagrams are built. (they were friends and coworkers, BTW).

    personal note: for me it was significant to know about a person in the context of a Sci-Fi writer, and then study some of his (considerable) contributions to other fields ... sort of a geekish sense of closure ;)

    --
    Working for necessity's mother.
  85. Re:Wont work. by guybarr · · Score: 2

    why ? verification.

    It's the oldest engineering axiom, but it seems to need to be stressed out more (in bold font, even :) ):

    if it is not tested, it doesn't work !!!

    and verifying orion means you need many test flights (for statistical confidence).

    So your attitude of "build it just in case, but don't fly it." although a nice idea, is impractical. to build it requires that you test it.

    --
    Working for necessity's mother.
  86. Ludicrous? by Vulture_ · · Score: 1

    What's so ludicrous about that? I thought of something similar when I was a kid (13ish, IIRC), albeit using conventional explosives instead of nuclear blasts.

    --

    The only way the typical /.er can pick up a chick is with a forklift. -- AC

  87. Project Orian by Anonymous Coward · · Score: 0

    Wake-up good people! This type of space travel has already been accomplished but it is "extreamly dangerious" and is highly unpredictable. So far we have not been able to effecively stablize such a means of travel where it is both safe with perdictable results. I really doubt that this will ever be accomplished in a safe and a reliable mannor. I myself will not again venture into such an undertaking.

  88. George Dyson by Thomas+A.+Anderson · · Score: 1

    I've read George Dyson's Bydarka book - is he still making them?

    For the erst of us, a Bydarka is an ilutian kayak made of whale bones and seal skins. george made (makes?) them from aircraft grade aluminum and coated cotton burlap. You have to see the book in order to understand how beautiful they are.

    There's also pictures in the book of his tree house - about 80 feet above the ground!

    --
    Personally its not God I dislike, its his fan club I cant stand (bash.org)
  89. Pusher plate/Cavalier by SharpNose · · Score: 1

    There's a reason to not go hemispherical. You want to capture as much forward-component of moving explosion product as you can, yes, but you also don't want to have to push around too much pusher plate. That being said, you could do the math to determine what size of circular flat plate is optimal. I get the feeling that the actual shape of the plate wouldn't matter a whole lot (hemishpere, cone, paraboloid, etc.) - you'd just be adding useless mass.



    I've heard of the Orion ship for years and I've always found the notion very intriguing, but the notion of a ground-based launch using actual Orion propulsion just makes me laugh, regardless of how well it might work!



    Prior to reading this /. review, I had heard that it was in fact the Cavalier Corporation and not Coca-Cola who was consulted for their experience inautomatically handling and dispensing cylindrical objects.