Talk:Nuclear electric rocket

Dubious choice
The choice of pebble bed for space is easily disproved on the grounds of power density. All the research from KIWI to the present (SAFE-400) states that in order to keep the thing light we need high temperature, densely packed systems such as fast metal cooled reactors or hexagonal pin fueled, high temperature gas cooled reactors. Furthermore the notion of safety from graphite is silly since graphite burns. Safety comes from ruggedness and spoiler pins inside the reactor which arrest the reaction. The key elements to NEP, as they are being pursued today are:
 * A compact reactor core
 * A gas turbine or stirling engine
 * A compact heat rejection system such as heat pipes
 * A high power propulsion system based on plasma propellants

The SAFE-400 is the current best of tech for items 1-3. The best of tech choices for 4 are VASIMR, DS4G and PIT. 68.226.119.204 (talk) 18:07, 22 February 2009


 * How would the graphite burn if it's in space? There's no way the reactor core would be exposed to oxygen, unless something went horribly, horribly wrong. And at that point, you've probably already lost the spacecraft. —Preceding unsigned comment added by 174.54.122.105 (talk) 10:35, 27 July 2010 (UTC)

Structure
Sorry, but I think this article needs a serious restructuring. In my opinion one of the first sentences should clarify the benefits and applications of this type of propulsion. What is the overall efficiency actually achieved and theoretically expected to be achieved and how does it compare to chemical and other alternative types of rocket propulsion ? What range of power output is possible and what mass can be moved by it from where to where ? I mean, you wouldn't expect to be able to get a shuttle off the pad by that methode, right ? I know, it is easy to complain here instead of writing something, but I simply do not have the necessary information. Only thing I just found on YouTube and which brought me here for more info was a statement by a Russian engine designer where he compares different types of motors as kerosene/LOX 3.5 H2/LOX 4.5  nuclear 9 and nuclear electric 45. I believe it was the speed of the exhaust gases in km/s. Would be nice to be able to compare other parameters like specific impulse and things like thrust per wheight etc. JB. --92.195.2.149 (talk) 11:52, 2 July 2021 (UTC)

Electrolysis and acceleration or mass ejection
Given a large piece of ice, found notionally near Saturn or Jupiter, or the core of a comet, and a fission reactor of substantial size, is it more plausible to make steam and blow it out of the back, or to make ions, and electrically accelerate them? The former is a staple of science fiction stories. Electrolysis would make Oxygen which could be useful, but also might allow accumulation of Oxygen and Hydrogen for use in chemical rocket motors, for manoeuvring. It also would avoid a radioactive exhaust. Midgley (talk) 21:56, 9 April 2023 (UTC)