First I am reading about nuclear engines applied to Starship. I wonder if it would be more practical to launch the reactor, fuel, and propellant into orbit using conventional rockets. Later a mission could pick up this Nuclear rocket engine and use it as a sort of booster while not inside a strong gravitational field. Ofc that doesn’t sound like Starship at all.
Did you read to the end? That's the idea he ends up with: only use nuclear propulsion for space-to-space travel where you don't care as much about shielding.
Nuclear Conversion for Starship
41–50 of 155 posts
Re: Nuclear Conversion for Starship
#42Earlier quoted context omitted.
Name me a country willing to give Elon Musk control of fissile material, however indirect.
Starship and the booster already collectively carry 70 kiloton-tnt-equivalent masses of liquid methane and oxygen. As a weapon of mass destruction, it's hard to beat relativistic impact.
> relativistic impact
You... er, realise they're not actually starships, right? At the speeds they go at (or would go at if they could take off without exploding) there is no significant relativistic effect.
Re: Nuclear Conversion for Starship
#43The summary of this methodical and enlightening article from an excellent source for mathematically backed science fiction / space travel is: No. Nuclear is not worth it for starship, as the added engine weight limits the additional delta V and the additional challenges of handling nuclear material.
Nuclear powered space tugs is a particular rabbit hole I’ve spent too much time on.
See, for example, this Boeing design: https://www.projectrho.com/public_html/rocket/spacetug.php#b...
Re: Nuclear Conversion for Starship
#44AFAIK, the only nuclear rocket that makes sense is landing a reactor on an icy comet and using it to shoot super heated steam wherever you want thrust. #seveneves
The Project Orion design (shoot hundreds of fission bombs out the back and ride the shock wave on a reaction plate) is surprisingly practical, and probably our only way to get humans past Mars. It's just kind of terrifying.
“A moderate-sized nuclear device was estimated, at the time, to produce about 5 or 10 billion horsepower.”
https://en.m.wikipedia.org/wiki/Project_Orion_(nuclear_propu...
Re: Nuclear Conversion for Starship
#45Nuclear power gives you more energy, but you're still limited by how much reaction mass you can carry.
The plans that work look like early 1960s NASA plans - build infrastructure in orbit, assemble nuclear power interplanetary craft in orbit, nuclear power is from planetary orbit to planetary orbit only. That was Wernher von Braun's "Man Will Conquer Space Soon" plan.[1]
The Apollo program, at US$20 billion, was the economy version. To the moon and back, no space station, no permanent infrastructure in space.
Re: Nuclear Conversion for Starship
#46The design is not advanced enough, they should be thinking of https://en.wikipedia.org/wiki/Fission-fragment_rocket So here is my science fiction theory: fusion will never be possible, but fission already is. So in the galactic civilization, rare uranium is the most valuable resource since it enables interstellar travel. Uranium is only produced in the collisions of neutron stars, so we are lucky to have any. We shou…
I think we might have enough.
"He noted that fast breeder reactors, fueled by naturally-replenished uranium extracted from seawater, could supply energy at least as long as the sun's expected remaining lifespan of five billion years"
https://en.wikipedia.org/wiki/Uranium_market#Available_suppl...
Re: Nuclear Conversion for Starship
#47Earlier quoted context omitted.
Nuclear rockets are useless for launching things into orbit. They don't have the thrust-to-weight ratio to get off the ground. Nuclear rockets are useful because they have high specific impulse which means using less fuel for thrust.
One of the core teachings of Kerbal Space Program.
Nuclear lightbulb is of course highly theoretical, but scientifically/engineeringly plausible at the least. [3]
[1] https://forum.kerbalspaceprogram.com/topic/173818-181-1122-k...
Re: Nuclear Conversion for Starship
#48Earlier quoted context omitted.
The Project Orion design (shoot hundreds of fission bombs out the back and ride the shock wave on a reaction plate) is surprisingly practical, and probably our only way to get humans past Mars. It's just kind of terrifying.
Yup, it’s scary. “A moderate-sized nuclear device was estimated, at the time, to produce about 5 or 10 billion horsepower.” https://en.m.wikipedia.org/wiki/Project_Orion_(nuclear_propu...
Re: Nuclear Conversion for Starship
#49Earlier quoted context omitted.
I'm going to go out on a limb and say Niger, CAR, Palau, etc don't have access to highly enriched uranium.
Who says it has to be highly enriched to start? https://en.wikipedia.org/wiki/List_of_countries_by_uranium_r...