Wednesday, October 3, 2012

If You Have Warp Drive You Need...

... Impulse drives.  According to C/Net, researchers at the University of Alabama at Huntsville, Boeing, NASA and Oak Ridge National Laboratory are working on nuclear fusion powered impulse drive.  And get this:
"The fusion fuel we're focusing on is deuterium [a stable isotope of hydrogen] and Li6 [a stable isotope of the metal lithium] in a crystal structure," Txchnologist quotes team member and aerospace engineering Ph.D. candidate Ross Cortez saying. "That's basically dilithium crystals we're using." Let's pause and savor that for a moment. Dilithium crystals. Awesome.
In the Star Trek universe, of course, warp drives get you from star system to star system and impulse drives get you around inside the systems, below light speed but still much faster than our current, chemical combustion engines can get you around. 
(Ph.D. student Ross Cortez)

If you're an old NASA geek, you'll know this isn't really new.  As early as 1963, NASA had a program called NERVA - Nuclear Engines for Rocket Vehicular Applications (video of a test firing).  There have been many options considered, from using nuclear power to create ion drives (the Cesium ion drives that have flown in deep space have been conventionally electrically operated) to setting off hydrogen bombs behind a sort of blast shield, to a fusion reaction.  Setting off small nuclear explosions in a combustion chamber was the heart of another NASA project, Orion, which actually traces its roots to the Manhattan Project in WWII.  It is widely acknowledged that political forces caused these programs to be shut down, not technical reasons.  There are simply too many people who panic at the mere mention of the "N" word - Nuclear, in this case.  Setting off successive, tiny (less than 1 ton yield) bombs sounds like "impulse power" to me. 

These ships will have to be built in space because the engines will emit radiation.  All of that practice building things for the Space Station might come in handy after all.  The current program is looking at ways to run a fusion reactor as a controlled thrust source that can be turned on, the ship accelerated to the desired velocity, and then turned off until it's needed again.  The Z-Pinch fusion or magnetic containment would keep the fusion flame (the equivalent of a Hydrogen bomb going off) from damaging the ship, and allow much higher velocities than we can currently achieve.  They estimate speeds of over 62,000 MPH are possible, which would reduce a trip to Mars from 8 months to about 6 weeks.  This could make routine flights around the solar system possible.  For the folks who freak out over radiation, using a nuclear rocket would expose the crew to less radiation than our current technology, because they'll spend less time exposed to deep space, and the gamma radiation that comes in from around the universe.



3 comments:

  1. Footfall, by Niven and Pournelle, may not have been the earliest novel speaking of using nuclear bombs as an impulse drive, but it's the first one I can recall off-hand. I've read everything Heinlein, Asimov, and several other early SF authors wrote, but I can't recall that particular method in their writings. "Fusion" drives did show up, though, much earlier than NERVA.

    I have often wondered how much science derived from scientists and engineers reading the early SF authors - like H.G. Wells and then the SF authors of the 40's and 50's - and then attempting to turn those ideas into reality?

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    1. I have often wondered how much science derived from scientists and engineers reading the early SF authors - like H.G. Wells and then the SF authors of the 40's and 50's - and then attempting to turn those ideas into reality? My hunch is that it's a lot. It's also pretty symbiotic, with the SF authors taking what they can learn about new theoretical ideas, or new technology, and stretching them out along a "what if?" trajectory.

      Mrs. Graybeard has a collection of "Electrical Experimenter" magazines that are approaching 100 years old. They were edited by Hugo Gernsback, who went on to some fame in Sci Fi (to put it mildly). These are just amazing to read for the insights into the future that this wonderful new "electricity" stuff would bring. Can you imagine drying clothes without hanging them outside? Why is it that no one in New England would even consider not heating their house in the winter, but nobody has thought of a way to cool them during the summer? Could electrical machines some day take the place of soldiers?

      The Star Trek original series communicator pretty much became the flip open cell phone. The tricorder that they use to monitor health and vital signs without contacting the person is just about here. There's an X-prize to create one, but I've read of many devices that emulate at least part of one.

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    2. Today's mail included news of a possible claim for the Tricorder X-Prize less than a day after this comment.

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