# RuBisCO

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1. ## Would Or Could A Nuclear Saltwater Rocket Be Converted Into A Plasma Rocket With A Magnetic Nozzle?

Here are my spreadsheet calculations. Consider an NSWR of 147 GW with a thrust of 5 MN and an Isp of 6000 s. It would have a total mass flow of 85 kg/s. If we assume an amazing fission efficiency of 90% while using a 2% uranium solution of 80:20 U235:U238, then only 0.224 kg/s of the uranium solution would be used, of which only 2 g/s of U235 is consumed. This means almost all of the 85 kg/s is water coolant, with some lithium salt and deuterium as well to provide fusion boosting, but that can be included in the uranium solution. Now the big question is: can 85 kg/s of water cool the nozzle and plenum chamber? This engine would produce 147 GW, which would heat the uranium solution as high as 46.3 x 10^6 Kelvin (assuming a heat capacity of 14.18 J/g°C for a plasma of 2 parts H and 1 part O). Fission of Lithium 6 and Lithium 7 to tritium, as well as T+D fusion, should be possible and can thus assist in the burn. I will assume this is occurring and is covered in that amazing fission efficiency of 90%. Now the rest of the 85 kg/s of water coolant would have an average temperature of 122,000 Kelvin, still a plasma that will vaporize anything. Obviously, the temperature is not the average of the water coolant at the nozzle and plenum chamber walls. Maybe, just maybe, we could get by with film cooling, having a thin layer of non-plasma water steam along the walls keeping the plasma from melting the walls. Otherwise, the only other solution is a magnetic nozzle. For a magnetic nozzle, we would likely need to switch to liquid hydrogen as coolant to cool the "high temperature" superconducting magnets. We would also still need film cooling as well. The advantage of liquid hydrogen is that our Isp would increase considerably. The average molar mass of water plasma is 6, and the average molar mass of hydrogen plasma is 1, so the specific impulse would increase by sqrt{6/1} or 14,697 s from 6000 s. Also, our thrust would decrease to 2 MN from 5 MN (with a mass flow now of 14 kg/s). This is not a problem considering that shrinking down an NSWR to 147 GW to begin with is likely asking a lot; we can expect terawatt NSWRs easily! The disadvantages of a magnetic nozzle include how to keep the high-temperature superconductors cool with all the heat from the continuous nuclear explosion, as well as neutron irradiation. Again, we would need to have film cooling with hydrogen gas as well as refractory materials that will not impede the magnetic field of the superconductors much. Next, hydrogen has very poor volume and mass density compared to water. Even with the superior Isp, the tanks for hydrogen would still be 5.6 times larger in volume than water tanks. Assuming spherical tanks, the surface area needed for hydrogen tanks is 3.1 times more than water tanks. Even still, 27 tons of water would need a tank of 27 m³ and would weigh 0.2 tons at 5 kg/m². This would be equivalent to 10.5 tons of LH2 in a 150 m³ tank that would weigh 1.4 tons at 10 kg/m². Either would provide a ΔV of ~3 km/s for a 500-ton spacecraft, so clearly even at that low ΔV, Hydrogen would still save ~15 tons, and the weight savings only goes ΔV goes up. In conclusion, a superconducting nozzle may be necessary to keep the plasma from touching the nozzle and plenum chamber walls. It would have the added benefit of using hydrogen fuel with higher Isp and reducing the minimum thrust an NSWR can provide. The extra tankage for hydrogen is negligible.
2. ## [KSP 1.12.3] Astronomer's Visual Pack - Beyond (v4.13 - July 17th, 2022)

Yeah I only got ride of it after removing the whole glow.cfg file
3. ## [KSP 1.12.3] Astronomer's Visual Pack - Beyond (v4.13 - July 17th, 2022)

Yeah so I go into it AstronomersVisualPack\AVP_Configs\Stock\Duststorms.cfg, removed all but Duna, restart the game... and its still there on Moho.
4. ## [KSP 1.12.3] Astronomer's Visual Pack - Beyond (v4.13 - July 17th, 2022)

Weird problem: I'm seeing cloud effects on planets that should not have clouds, Mun, Moho, etc, is that normal?

6. ## Meta Modding KSP 2: What We Know

I just want to start real simple at first: how to I install a new flag of my own design?
7. ## Antimatter Rocket-like Exhaust Plume... Very Little Expansion If Any in Upper Atmosphere?

Anything hitting atmosphere will slow down: the masons, atomic fragments that can be magnetically funneled out an exhaust, produced in even the cleanest antimatter-matter reaction of anti-protons and protons while hit atmosphere before they decay, creating an explosion behind it of superheated plasma. Sure in the vacuum of space it will produce a beam that will decay into nothing as the masons eventually end up one way or another as gamma rays.
8. ## totm oct 2022 DART: Double Asteroid Redirection Test

Now this is just my uneducated opinion as a biochemist and not a physicist but I suspect more holds asteroids together then gravity, electrostatic forces, mechanical adhesion (bits locking and hooking together), etc.
9. ## [1.12.x] Parallax - PBR Terrain and Surface Objects [2.0.8]

I'm still working on it, but it is based on this: https://kerbalx.com/RuBisCO/Mini-Hexopod
10. ## [1.12.x] Parallax - PBR Terrain and Surface Objects [2.0.8]

I assume this is already known but collision/clipping with rocks is intermittent and at random, sometimes crafts go through the rocks, sometimes they don't, not sure why.
11. ## How do you fix leaks in space?

I do like the idea, my dudes, of putting something in the coolant (ammonia?) that will clog and seal small holes.

13. ## What is the best energy source for an unmanned airship?

at ~50 km above the surface of Venus its like being in full sunlight on earth from all directions so you could put the solar panels on any surface, all around the balloon, even pointing straight down.
14. ## [1.12.x] Parallax - PBR Terrain and Surface Objects [2.0.8]

Really loving this mod!
15. ## The James Webb Space Telescope and stuff

Well never say never, remember there is now satellite services in which a symbiotic satellites docks to a rocket nozzle of the host satellite and then the symbiotic sat takes over the propulsion functions of the host.
16. ## The possibility and ethics of contaminating Mars. (Split from SpaceX.)

If Mars has life it is most likely subterranean and as such would take a lot for us to contaminate. If Martian life is not related to us, totally separate evolution of biochemistry then it most likely could eat us as well as we can eat plastic. Even if Martian life is related to us and thus could hypothetically infect us, most subterranean bacteria here on earth has no clue what to do in an oxygenated human body, geobacter and shewanella are harmless even to people who are immunocompromised. I understand CYA because of unknown unknowns means we need to take outlandish precautions, so here I what I propose: If ice coring samples of potential human landing sites find water ice under the ground (for making fuel for the return trip) and IF they find life in those cores then send a One-way trip of biochemists to figure out what that life is and determine how harmful it can be before sending us back, if ever, I volunteer. If we become infected with Mars life and can never return, so be it.
17. ## The James Webb Space Telescope and stuff

Watching that launch was extra scary considering the price tag and astronomical advancements this telescope represents. We still have 6 more months before everything ins unfolded and checked out.
18. ## The Ultimate Jool 5 Challenge Continued

Here is my submission to for the Jool Challenge. All 7 Kerbals landed on every moon in the Jool system. ISRU was used as well as the DLC packs. MechJeb was the only mod used to simplify all the transfers, landings and dockings, etc, as well as to provide orbital and surface data in every picture. Only one launch is needed, at a cost of nearly 1.5 million. Use KSP version 1.12.2. https://imgur.com/a/qnEOtsC More info can be found on the KerbalX page for the craft: https://kerbalx.com/RuBisCO/Jool-All-In-One-Mission-21
19. ## Short Lifetime For Nuclear Thermal Rockets In Space?

Well Zubin Drive it would be a beam of radioactive plasma, so white-purple. Its exhaust in atmosphere would be like a continuous nuclear explosion, in fact I seriously doubt that even if Zubin drive could work that it could work in atmosphere without just exploding. I think the others have covered the topic: we all agree water steam will be transparent to whiteish-blue.
20. ## Short Lifetime For Nuclear Thermal Rockets In Space?

Which is why I advocate for nuclear-water so that ISRU requirements are dramatically reduced, no need to crack water and cryoliquify hydrogen, also no waste oxygen. None the less I think with the present state of research H2/O2 is going to win out on the moon and CH4/O2 on Mars, nuclear only in nuclear power reactors to power ISRU at best. Human's are not Kerbals and as such I think there will be much political pressure against nuclear thermal rockets. I mean if it was up to me we would go with Zubin's continuous nuclear exploration, nuclear salt water engines, regardless of the fact they would spew a beam of pure nuclear waste out the nozzel.
21. ## Short Lifetime For Nuclear Thermal Rockets In Space?

That sounds like the worse of both options, you need to develop NTR and you need to make LH2 and LO2 via ISRU. Either have H2/O2 in space fuel economy with existing tech, or have nuclear-water with technology that has been proposed for decades but never developed.
22. ## Short Lifetime For Nuclear Thermal Rockets In Space?

Sounds like a standard electrolysis cell to me: Above you can see the hydrogen and oxygen are separated into separate pure gas streams by a proton-exchange membrane. Higher efficiency can be achieve using hydroxyl exchange membranes (alkaline fuel cell) the best I have seen and theoretically possible is 75%, but that is with electricity, which means means you have to count the inefficiency of making electricity. Lets say you use a nuclear reactor with a very efficient closed cycle helium baryon cycle of 50%, so your water electrolysis is going to be at best 37.5% total efficient. What is desirable is to have a more direct heat process, for example a sulfur-iodine cycle could do up to 50% efficiency from heat alone, no conversion to electricity.
23. ## Short Lifetime For Nuclear Thermal Rockets In Space?

Well that not scifi, we have the technology to crack water to H2 and O2, separate and cryoliquify, it just takes a lot of power and equipment mass. Nuclear-water would skip all that but at the cost of needing very new technology that has only be proposed and never tested at any scale, that being extremely high temperature steam in a nuclear thermal rocket.
24. ## How do I turn shadows off?

I did before, the best I can do is turn off "shadowmaterial" in the EVE settings, but this does not eliminate shadowing from sun light, just the shadows of the clouds. What is needed is to remove shadow casting altogether when below clouds from the sun, but keep it for headlights and lights. Instead shadows from the clouds are rendered on top of lights, when it should be the reverse and lights should render on top of shadows.
25. ## How do I turn shadows off?

Still did not fix the problem but thank you non the less for the mod improvment:
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