Editing Nuclear salt-water rocket (section)

==Advantages==
There are several advantages relative to conventional NTR designs. As the peak [[neutron flux]] and fission reaction rates would occur outside the vehicle, these activities could be much more vigorous than they could be if it was necessary to house them in a vessel (which would have temperature limits due to materials constraints).<ref name="zubrin91"/> Additionally, a contained reactor can allow only a small percentage of its fuel to undergo fission at any given time; otherwise, it would overheat and melt down (or explode in a runaway [[Nuclear chain reaction|fission chain reaction]]).<ref>{{cite journal |last1=Hasegawa |first1=Koichi |title=Facing nuclear risks: Lessons from the Fukushima nuclear disaster |date=March 2012 |journal=[[International Journal of Japanese Sociology]] |volume=21 |issue=1 |pages=84–91 |doi=10.1111/j.1475-6781.2012.01164.x}}</ref> The fission reaction in an NSWR is dynamic, and because the reaction products are exhausted into space, it does not have a limit on the proportion of fission fuel that reacts. In many ways, NSWRs combine the advantages of fission reactors and fission bombs.<ref name="zubrin91"/>

Because they can harness the power of what is essentially a continuous nuclear fission explosion, NSWRs would have both very high [[thrust]] and very high [[exhaust velocity]], meaning that the rocket would accelerate quickly and be extremely efficient in terms of propellant usage. The combination of high thrust and high [[specific impulse]] is a rare trait in the rocket world.<ref>{{cite web |author=Braeunig, Robert |orig-year=1997 |year=2005 |title=Rocket propulsion |department=Rocket & space technology |website=braeunig.us |access-date=1 May 2016 |url=http://www.braeunig.us/space/propuls.htm |url-status=dead |archive-date=12 June 2006 |archive-url=https://web.archive.org/web/20060612212910/http://www.braeunig.us/space/propuls.htm}}</ref> One design would generate 13&nbsp;meganewtons of thrust at 66&nbsp;km/s exhaust velocity (or 6,730&nbsp;seconds ISP, compared to about 4.5&nbsp;km/s (450&nbsp;s ISP) exhaust velocity for the [[RS-25|best chemical rockets]] as of February 2023).<ref>{{cite journal |author=Zubrin, R. |author-link=Robert Zubrin |year=1991 |title=Nuclear salt water rockets: High thrust at 10,000&nbsp;sec ISP |journal=Journal of the British Interplanetary Society |volume=44 |pages=371–376 |via=narod.ru |url=http://path-2.narod.ru/design/base_e/nswr.pdf}}</ref>

The design and calculations discussed above are using 20-percent-enriched [[uranium]] salts. However, it would be plausible to use another design which could achieve much higher exhaust velocities (4,725&nbsp;km/s) and use a 30,000-tonne ice comet along with 7,500&nbsp;tonnes of [[highly enriched uranium]] salts to propel a 300-tonne spacecraft up to 7.62% of the speed of light and potentially arrive at Alpha Centauri after a 60-year journey.<ref name="zubrin91"/>

"NSWRs share many of the features of [[Project Orion (nuclear propulsion)|Orion]] propulsion systems, except that NSWRs would generate continuous rather than pulsed thrust and may be workable on much smaller scales than the smallest feasible Orion designs (which are generally large, due to the requirements of the shock-absorber system and the minimum size of efficient [[nuclear explosives]])."<ref>{{cite report |author=Stern, David P., Dr. |date=19 November 2003 |section=Far-out pathways to space: Nuclear power |title=From Stargazers to Starships |section-url=http://www-spof.gsfc.nasa.gov/stargaze/Snucfly.htm |access-date=14 November 2012}}</ref>