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Workable Fusion Starship Proposed
Adam Korbitz writes "A former colleague of Edward Teller — father of the hydrogen bomb — has published a new paper proposing a design for what could be the first practical fusion-powered spacecraft (PDF). As described at Centauri Dreams, the design has certain similarities to MagOrion, a 1990s-era proposal for a nuclear-powered spaceship with a magnetic sail and propelled by small-yield fission devices. The proposal's author also has links to the British Interplanetary Society's Project Daedalus, a 1970s proposal for an unmanned fusion-powered interstellar probe designed to reach 12% of the speed of light on its way to Barnard's Star."
I'm all for ideas like this but we won't be building things like this until we, as a planet, have a permanent manufacturing presence in space.
Moon colony, orbiting L5 colony, whatever it is it must be permanent and able to manufacture using locally sourced materials because building something like this from within the gravity well doesn't make economic sense.
"Bah!" - Dogbert
Edward Teller hired my Dad into the Physics department at UC Berkeley and I remember him as a gentleman - he was occasionally at our house. Once my parents had a costume party and Teller was provided with a bird costume - he did not want to wear the mask so he had these big white wings on. The SF Chronicle columnist Herb Caen ran a story the next day saying that Teller was dressed as the angel of peace. Until Teller died a few years ago, my Dad would occasionally travel to Berkeley to visit with him.
Because they are all dead or going to be soon.
That was very interesting as I knew what was going on with the associated news stories that are planted but never knew it was so aptly named. I wonder , do the movie promoters pay the people to do the articles, or are they just lazy, and if somebody writes free copy for them, they jump all over it.
As far as the Nuclear drive, my brother ( who is a Nuclear Engineer ) and I have discussed it for over 30 years and though it might work, it could also end up buried somewhere with a message "Do not open until Christmas 40010".
Really? Could a magnetic scoop then be used for braking on a ship that used a different type of propulsion? Because more than half your propellant on an interstellar journey is required due to the need for braking when you get to your destination.
Yes, absolutely. It has been proposed as a part of laser-boosted lightsail missions to other stars. A full sized collector scoop would work in interstellar gas, but you only need a relatively small magnet if you are plowing through solar wind (er... stellar wind, since it isn't Sol?). A superconducting cable spooled out of a probe and given a current could be used as a braking system to decelerate at a destination star. I recall seeing an estimate somewhere that the peak deceleration of a relativistic craft like this hitting the heliopause would be about 12g, not comfortable but very effective and cheap way to slow down. Magnetic sails have also been proposed as a way to accelerate in the first place, but in that case you are limited to speeds less than that of the solar wind itself, so it is more suited to in-system missions.
Magnetic sails have also been proposed as a way to accelerate in the first place, but in that case you are limited to speeds less than that of the solar wind itself, so it is more suited to in-system missions.
Is that really true? Many years ago, I read a fascinating book called "The Twenty Knot Sailboat". The author, strangely enough, was in the Air Force and stationed at a dry lake bed in southern California. He used to build models of fast sailboat designs and could only test them on rare occasions when there were flash floods and the lake bed would have a few inches of water for a few days a year.
His thesis was that the two things that limited the speed of a sailboat were the sail and the boat. He proposed to replace the conventional sail with a far more efficient airfoil and the boat with a hull on hydrofoils. Both methods were means to avoid drag so as to allow greater speed.
The relevant part was when he got into the theory of sailing and said that it had been proven that an iceboat (far more friction-free than any sailboat) could actually go downwind on a broad reach at a speed exceeding the speed of the wind driving it.
I'm not a sailor (or physicist) myself, but his explanation seemed reasonable to me. I do remember his sketch of the situation -- it had him standing near the stern, going downwind on a broad reach, moving forward with his pipe smoke trailing out behind him.
Any engineers out there want to evaluate the possibility?