Homer Hickam Speaks Out For Fission Rockets

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

Comments

Re:Plasma/Laser Powered Rockets

[spike hay]

Here is a link to that : here

Anyway, nuclear rockets are a great idea. A better one, you may have heard me harp on this before, is VASIMR. It is a plama rocket with a nuke power source. It will be around ten times as efficient as the nuke rockers. However, the VASIMR, unlike the nuclear rocket, it does not have enough thrust to launch from earth. It is more a slow and steady engine that runs for weeks instead of minutes. But the burnout velocity of a VASIMR can be vastly higher than a chemical rocket.
The nuclear rocket can provide cheap, efficient space launches with not too much radioactive fallout. In fact, if a nuclear rocket using helium as a propelent will produce no fallout at all. Since a nuclear rocket is about twice or three times as efficient as a chemical rocket, the amount of fuel you'd need would be slashed dramatically. A nuke rocket launch might only use 10% or less of the fuel that a conventional booster would.

It's under R&D.

It ionizes hydrogen with microwaves an then accelerates them with magnetic fields. While it doen't provide thrust like a chemical rocket, it certainly has many, many times more thrust than a ion engine. It has some oomph to it. For cheap launches, you really need somthing like the x-42 scramjet spaceplane. That would cut costs of launching by a factor of 10 with no giant lasers.

VASIMR will get a specific impulse of 30,000 seconds compared to 500 seconds for the shuttle's engines. A specific impulse is the number of seconds 1 kg. of fuel could produce 1 kg. of thrust. The specific impulse of the VASIMR is 60 times better than the shuttle. That is many times better than the ~1500 seconds you'd get with the nuclear rockets.

That would allow cheap interplanetary voyages anywhere in the solar system, using very little fuel. Using these engines, you could get to Saturn in less than a year. It would also allow slow intersteller trips of around 1% the speed of light.
Also, VASIMRs could be easily, cheaply, and quickly refueled for more missions.Interplanetary travel could become cheap. I bet each ship would cost around 5 billion dollars initialy. After that, it's cheap. After each trip, an X-42 could come and restock the ship with fuel and supplies. That would only cost around 50 million. We could send tens of thousands to colonize Mars.

BTW: On this article, it says the VASIMR gets 10,000 seconds. It can reach 30,000 with further development.
Read about the VASIMR here
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