Talk-Polywell.org

"Thought" they can be re-used isn't the same as data. Ironic from someone singing the praises of a Power Point rocket. From The Rocket Company by Patrick Stiennon and David Hoerr "An off-the-shelf RL10A3-3A, with 16,500 pounds of thrust has been run for over 30 minutes without any maintenance. Prat...

Unknown what the lifespan of a Triton or smiliar NTR would turn out to be since they haven't been developed yet. Of course..what is the life span of a chemical rocket? Since our chemical rockets to date are expendable, we really don't know how many times they could be re-used. RL-10s are reliable w...

To what appears to be your basic point: it is a lead pipe cinch that nuclear rockets would sometimes suffer catastrophic failure like chemical rockets, with resulting loss of life and destruction of payload. No matter what improvements in design technology are made the risk will never be zero. No, ...

I suspect the math is beyond your reach. No offense...but perhaps you could explain to us mathematically why you think chemical rocket plus your propellant depots would win out over say NTR like Triton. A Triton launched from earth by a chemical rocket gets fueled in orbit (either/or earth orbit or...

Betruger wrote: I get it. The math is nowhere near beyond me.

So show me.

Given a one tonne payload, how much hydrogen and oxygen propellant will it take to achieve 3 km/s delta V? 6 km/s delta V?

No NTR don't but I think a variant called "Timberwind" Quoting a post from nasaspaceflight's NTR/BNTR/NEP thread: "You may have heard of another NTR design looked at in the early 90s under a program called Timberwind--this was a "particle-bed" design, where instead of having fuel elements in channe...

Betruger wrote:It might be me, but the artistic embellishment on those graphics drown out the actual meaning. I can't see what they're supposed to communicate.

In addition to the illustrations I include a verbal explanation and math.

I suspect the math is beyond your reach.

HopDavid, I think you are missing the key reason/assumption why LEO is half way to anywhere in the system -- Once in LEO everything takes significantly less delta v (which I know you are aware of). If you only bring enough fuel to get to LEO, and then meet up with a refueling station, your range is...

No NTR don't but I think a variant called "Timberwind" http://en.wikipedia.org/wiki/Project_Timberwind was supposed to but was never developed. Here is a thread where various forms of nuclear propulsion are discussed. The key is to reduce the cost to orbit by a couple orders of magnitude by some me...

16 km/s (or more) delta V budgets plus Tsiolkovsky's rocket equation preclude profitable extraterrestrial mining ventures. With chemical rockets. That 16 includes 9 or 10 to rise from earth's surface and achieve orbit. NTR doesn't have the thrust to weight ratio needed to make the ascent. And, as I...

GIThruster wrote:I think when P&W did the study back in 2004, they estimated $1B for a working system.

Cite, please.

@HopDavid I agree with you that rocket fuel derived from lunar water is the most valuable product on the moon. Without this resource it is very hard (Impossible?) to make a case for lunar gold. With this resourse, and adding a filling station in LLO (1.87 km/s delta V), then on to EML1 (0.64 km/s d...

IMHO, it's all in the numbers, and pretending there might be gold on the Moon won't change the realities we face. Pretending? This notion comes from looking at the LCROSS ejecta. See the October 2010 issue of Science . And propellant high on the slopes of earth's gravity well changes the numbers a ...

To say nothing of lunar mass drivers I believe lunar mass drivers will come to pass. But not in the near term. and possibly a space elevator on Mars at some point. While I regard lunar mass drivers as plausible, a Mars elevator isn't. That would be a hugely ambitious project. The figure you gave fo...

I see that you didn't read and understand the full NASA spaceflight forum thread. The gist of the thread includes advances expected and efficiencies obtained from SpaceX, VASIMR and lunar derived fuel which could result in sweeping changes in space transportation costs. Warren's original post does ...