Talk-Polywell.org

Obama Space Plan Is At Outline Stage

NASA Administrator Bolden: “We believe the technology shortfall we face is so fundamental that incremental changes or tinkering on the margins will not be sufficient to address current and future needs,” says Bolden, who emerged after a period under wraps as the public face of the new space policy. “Rather, a fundamental rebaselining of our nation’s exploration efforts is needed. We must invest in fundamentally new innovations for space technology.”

Yo. Polywell. Field Reversed Configuration. Dense Plasma Focus. Mach-Lorentz Thruster. For starters.

If Polywell proves fruitful (not to dash hopes), then there is an almost 100% certainty that it gets used in the advanced propulsion aspects of manned flight.

Think about that for a second.

Mars in days.

Reading the article, a lot of it actually sounds quite ok. They're talking about VASIMR, inflatable habs, in situ resource utilization - all sorts of good stuff that we should've pursued years ago.

Delta IV "Heavy" and Atlas V "Heavy" are almost ready to go in terms of providing medium lift. We'll have to wait and see with Falcon 9. I hope SpaceX is successful and adds some competition to this industry.

Still, I'm doubtful about commercial interests' ability to develop HLVs, and I'm also doubtful about building something like a VASIMR powered human exploration vehicle using medium lift launches.

Cargo launch by mass driver (giant gun or maglev sled going up a mountain) might need to be looked into again. Theoretically, I like the idea of a space elevator using nanocarbon fibers. To my understanding, once the nanocarbon chains can be grown kilometers long, the numbers work. However, I'm concerned about maintaining security around a space elevator. Here's a question to the engineers and physicists: what would happen if terrorists crashed a plane into a space elevator and the cord broke? (I don't know whether an aluminum bodied aircraft would snap a, say, 10 meter thick cord of nanocarbon filaments or not.) Would the whole upper half of the structure be pulled out of orbit by the impact and come down in pieces all over the planet? Or would it spin off into space? Could a space elevator be turned into a crude WMD? If any of this could happen, I'd feel safer with something that launches on a rail up the side of a mountain, because it can't be used to cause massive destruction.

Heck, I'd prefer nuclear-powered RLVs. There were lots of atmospheric nuclear tests in the 50s - a single RLV blowing up somewhere over the ocean and releasing a small amount of fallout would be far less significant than that. You'd have to have dozens of nuclear RLVs failing and blowing up in the atmosphere to match 1950s nuclear testing.

CaptainBeowulf wrote: ... Theoretically, I like the idea of a space elevator using nanocarbon fibers. To my understanding, once the nanocarbon chains can be grown kilometers long, the numbers work. However, I'm concerned about maintaining security around a space elevator. Here's a question to the engineers and physicists: what would happen if terrorists crashed a plane into a space elevator and the cord broke? (I don't know whether an aluminum bodied aircraft would snap a, say, 10 meter thick cord of nanocarbon filaments or not.) Would the whole upper half of the structure be pulled out of orbit by the impact and come down in pieces all over the planet? Or would it spin off into space? Could a space elevator be turned into a crude WMD? If any of this could happen, I'd feel safer with something that launches on a rail up the side of a mountain, because it can't be used to cause massive destruction.

Worry thyself not at all.
The lower end of a nanotube elevator would look not unlike a long sheet of newspaper or the equivalent sheet cut or rolled or.... But if it were somehow cut, the upper end would lift off into space and the lower end would flutter down to the ground.

Watch out for falling capsules, but ANYTHING that puts energy into capsules has the same worry.

The truly nice thing about tethers is that you don't really need a single long elevator. KITE/HASTOL (Hypersonic skyhook) could also do the job.

When the upper end lifts off into space, would it have escape velocity? I expect it would just settle into a higher orbit, ready to be recaptured and reused when it comes time to repair the thing.

I don't worry about catastrophe with a broken elevator, but I do worry about the cost. Could we get the Star Wars program working? I want some lasers hanging out near my tower, ready to vaporize any micrometeorite or terrorist that gets too close.

Not much we can do about micro-meteoroids, but they are not THAT big a deal. It is the space junk that is the real problem.

Personally I'd like to see an effort to knock down some of the junk we've put up there. Tethers Unlimited has a pretty good way to prevent MORE junk from accumulating, expecially in this age of micro-sats. But someone needs to figure out how to use that type of technology to reduce what is there.

I looked into carbon fiber for a space elevator and I'm sorry to say that it is not likely ever with the route we are taking.

The bonds in the material can not support the weight of an earth anchored tether. Or should I say - if we can reach ultimate bond strength we are very close to the limit.

This plan would be great if it didn't sound exactly like what you'd do if you wanted to remove all major political support from NASA so as to be able to gut its budget with impunity in the out years...

I was just calling their bluff. I knew they weren't serious.

Didn't Paul March or someone give a rough estimate for how much they'd need to take ME R&D to the next step? Wasn't it something in the low-mid 5 digits or very low 6 digits?

Considering that Woodward was one of the few researchers who got a semi-kudo from the now-defunct Breakthrough Propulsion Physics program, you'd think NASA could cough up a few taxpayer dollars for him.

CaptainBeowulf wrote:Still, I'm doubtful about commercial interests' ability to develop HLVs, and I'm also doubtful about building something like a VASIMR powered human exploration vehicle using medium lift launches.

I had been wondering about what the future of a > 100mT HLV would be, given that there's an HLV R&D line item for half a billion each year in NASA's proposed budget out till 2015 and the Augustine commission flatly stated we need one. Are they going to do the leg work and just hand it over to commercial? The media seemed to be assuming/insinuating as much.

Then I listened to this press conference. Looks like NASA will be building a launching rockets again in the future although not for another decade at least....

Considering that Woodward was one of the few researchers who got a semi-kudo from the now-defunct Breakthrough Propulsion Physics program, you'd think NASA could cough up a few taxpayer dollars for him.

Well, most of science thinks he's a kook, so no, I wouldn't expect that. He's gone out on a limb and needs to prove he's not a kook before anyone gives him the time of day.

MirariNefas wrote:

Considering that Woodward was one of the few researchers who got a semi-kudo from the now-defunct Breakthrough Propulsion Physics program, you'd think NASA could cough up a few taxpayer dollars for him.

Well, most of science thinks he's a kook, so no, I wouldn't expect that. He's gone out on a limb and needs to prove he's not a kook before anyone gives him the time of day.

The problem with the "kook" designation is that it delays attempts at verification or refutation.

We could even just start with the math. Why is the Mach-Einstein conjecture wrong.

Science is just too full of orthodoxies these days. I don't like it one bit. It delayed a real look at "Cold Fusion" by 10 years or more. It has given us dubious Climate "Science" etc.

MSimon wrote: Science is just too full of orthodoxies these days. I don't like it one bit. ... (truncated)

Yes, so right. Why is everyone so bl**dy sure they're correct?