From Rob Woudenberg 's link above...
Additionally, there’s also low-energy nuclear reactions (LENR), which we’re working on here. We’ve got 22 years and hundreds of experiments now on low-energy nuclear reactions which indicate that this is real. Plus, we now have a theory that indicates that it’s condensed-matter nuclear physics.
So LENR appears to be collective effects, not particle physics. It seems that you can get around Coloumb barrier by forming ultra weak neutrons using heavy electrons. This not only enables you to form the neutrons, but also convert the gamma radiation from beta-decay into thermal energy so that you don’t need as much radiation protection. LENR is expected to be anywhere from 20,000 to 3 million times chemical efficiency, and if we can get that in place it will truly revolutionize space.
The VASIMR is a high-thrust magnetohydrodynamic engine for spaceflight.
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I didn’t realize the LENR was being investigated that heavily by NASA.
Well, it’s not heavily, I mean we have a $200,000 to $300,000 a year effort. We’re also cooperating with people on this, but I can’t divulge details under cooperative agreements.
LENR purportedly also produces transmutations, which is quite interesting. For in-situ resource utilization, if LENR works, perhaps we can take elements on the planet and possibly transmute them into something we need.
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What about something like the IEC Polywell reactor that Dr Robert Bussard was working on for the Navy? Is that worth pursuing?
Yeah, I’m very familiar with the Bussard stuff. That’s aneutronic fusion, using pB¹¹ or D-³He, and it may be possible. It’s yet another of five or six very advanced energetics technologies that we need to study more heavily than we are now.
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I just read about the 100 Year Starship program, so hearing you discuss MHD, LENR, anti-matter and other advanced propulsion makes me wonder if NASA isn’t going back to the drawing board in some ways.
Well, if you look at space access, it’s essentially done today the way it was done in the ’50s. These are basically ICBMs — modernized versions of German V2 rockets. It’s chemical propulsion, and we’re out at the ragged edge of the performance of chemical rockets. We need something a lot better than that if we’re going to make spaceflight safe and affordable.
What we’ve realized at NASA is that if you’re going to do safe and affordable manned space exploration, then you’re going to need another whole level, another whole generation of the technology.
Back in the Bush-era space program when 100 YSS was launched, this vision was put in place with essentially conventional technology. Over the years and in many, many projects, NASA has warned that if you want revolutionary goals like humans in deep space you need revolutionary technologies. These aren’t cheap to develop, and we had to divert resources into developing them, which we’re doing.