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About RuBisCO

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  1. Animal sense of disgust if very different from ours, my dog loves rolling in snake vomit and eating horse poop, but a chopped pickles she will instantly spit out.
  2. Tasting everything you touch might have downsides, at least if you have a sense of disgust.
  3. Well hyperedit works well enough so far, but I mean I need tug boats and what not to get it from the pad or runway to the ocean, sink it, all that.
  4. So far in my experiments to mimic a sea dragon I have found it is very easy to get a rocket to launch bobbing at sea... the problem is how to get it out at sea to begin with.
  5. Well I was reading the wiki, which is clearly inaccurate. I should have know that because ~15 years ago I made BS articles on Wikipedia and some of them are still up there!
  6. Come on man, we should have a little more selfestim and not call are selves dirt.
  7. So that 350 MN liquid nitrogen cooled and nitrogen pressure fed engine simply nothing could compare at least in raw thrust! It would take 50 F1A engines to match that and less tnen 40 could be sqeeze under the 23 m diameter sea dragon so F1A engines simply would not do. A solid rocket much bigger then the biggest at the time (AJ-260-2, 6.6 m wide 17.7 MN, never launched but ground tested once) could have fit under 23 meter and match or exceeded 350 MN, but would be fueled on land and have to be floated out there, which being much denser then kerosene/lox (which would be fuel up at sea to help the rocket reach vertical orientation) would make floating the thing out to sea impossible.
  8. Fun fact, in old English "man" meant all humans, the sexes were described as "wyfman" and "werman", I think we should return to that system, keep "woman" but bring back "werman" for male persons and throw out "human", "humankind", "humanned", etc, make the hu- unnecessary. For kilometers all around, dead fish, dolphins, everything.
  9. About the plume: The first stage in the '62 conceptualized design was pressure fed Kero/LOX that likely would be inefficient and produce a lot of particulate, also in this alternate universe it is quite possible they design it to be solid fueled first stage instead. Plutonium: Perhaps for something else nuclear powered or atomic bomb powered Mixed U235/Pu239 reactors or fast neutron Pu239/U238 could also be a possibility, and of course Pu238 for RTG power, but considering the shows bent for the grand I've got my fingers crossed to see a manned Orion!
  10. It would be great if we can have multiple robotic part controllers that we can activate/deactivate by moving up and down priority via a hotkey (action group) instead of having to manually change their priority in the click menu. Example: So I have this robot: I want to have multiple controllers for walking, walking right, left, turning in place, crabing, etc, but I need to manually bring one up to 5 and bring the others down to 4 or lower. If I turn the play action off on one while the other I want is at the same priority it slows/jams what ever the action stopped at.
  11. Rail guns would be able to accelerate a tiny package really fast into a orbit that would crash back down into the moon (from behind) if it does not have thrusters and fuel on it to circularized its orbit. Military rail guns can shoot a several kilogram tungsten dart at 2.4 km/s out of a gun that is only a few meters long, that would be more then enough to enter lunar obit assuming it has thrusters on it to circularize its orbit. The problem is we want to throw something bigger then a few kg, and it also has to withstand g-forces of > 100,000 G out a rail gun! A magnetic mass driver (without all the arcing/melting parts of a rail gun) say 100 m long throwing a 1 ton package, to 2.1 km/s would put it under 4500 G: that is way better then the rail gun, plus with some very good flight controls a package could come back from orbit and fly into a mass driver pointed the opposite direction and decelerate back to zero, bring cargo down (assuming it can withstand the deceleration) or at the very least recycling the package, and all of its orbital energy can be stored in capacitor banks to launch the next package! Such a mass driver system would be able to bring cargo up and down much faster than a bean stock, but would require some propellant in maneuvering and orbit circulation fuel. Obviously humans still can't be used with such a system. Another idea that would require less cabling then a bean stock is a rotovator: a space ship either flies straight up from the moon or is held there by a tower, and a spinning swing many kilometers long in orbit flies over and picks up the ship, swings it into lunar orbit above it. If it brings down cargo of equal mass no energy is lost, otherwise the swing loses orbital altitude that would need to be boosted slowly by an efficient propulsion system. If the swing is long enough and spins slow enough then it can lift humans with g-forces low enough. I calculate a 100 km long radius rotovator would put the end point at 2.74 G, at 200 km long it is 1.29 G and at 300 km long it is 0.82 G.
  12. Oh the LOX would be a tiny fraction of that, in fact there would be a huge oxygen excess, to dump I guess. Yes the ratio is far better on Mars, because CO2 is easier to get there by far than water is (just suck it out the martian air, digging/minning equipment is needed only for getting water), unlike the moon where the ratio of water to carbon is more than 20:1, hence why the moon makes sense to have a hydrolox economy and Mars makes better sense to have a methalox economy, hence why Elon is betting on hauling methane from earth to low earth orbit to refuel ships destine for Mars, although it could also haul fuel to cis-lunar space to landers to the lunar surface and back and likely would be competitive at that for many years before a hydrolox economy on the moon is started up. Problems with hydrolox is that hydrogen requires double stage cryogenic cooling which is heavier, needs more energy and has yet to fly in space. The colder a cryogenic fuel is the harder it is going to be to transfer and move about. Methane and oxygen have the nice feature of both being liquids in useful temperature and pressure ranges, they can be stored together with a uninsulatd bulkhead between them (Warning: do not mix together, if mixed forms extremely unstable explosive cryogenic liquid, they will explode if even a bright light is shined on them!) Which means one set of cryogenic equipment that needs to go no lower then 50 K can freeze both down to their freezing points. Obviously hydrolox requires thermally separate fuels tanks (for long term storage, so far common bulkhead tanks have been done for hydrolox for weight saving proposes but for short missions), more insulation, oh and much bigger tanks: liquid hydrogen has the density of cotton candy, while liquid methane near its freezing point has the density of gasoline. Huge fuel tanks are not so much of a problem if your not going to fly through atmosphere. There is another solution, one I have not touched on because it is so underdeveloped, or rather has only had fragmented development over many decades: Nuclear water rockets. It requires orders of magnitude less equipment to just mine water, purify it, refreeze and pile the unwanted extra volitiles, and just run it through a nuclear rocket engine, then to crack water into hydrogen and oxygen and cryo-liquify them, extract extra hydrogen from the extra volitles, etc. The first problem though is that to get a nuclear-water rocket up to the same Isp as hydrolox requires operating at temperatures that have yet to be achieved for nuclear engines, we are talking about the need for rotating cores in which the nuclear fuel gets so hot it becomes a goo that needs to be held in place by centrifugal force. The second problem is water at extreme temperatures of ~3500 k is very corrosive, much of the gas is radicals of oxygen and hydrogen at that temperature rather then water, and squeezing that through pores of nuclear fuel that already has the resiliency of putty at that temperature is likely an engineering nightmare. Alternatively nuclear engines on water could be run at much lower temperatures, much more reliably and well developed technologically, but at significant cost to ISP, at an ISP of 200 s, 3 times as much water will be consumed getting it to Low lunar orbit then if we burned it via hydrolox. Worse even if we had a nuclear rocket engine that could do 500 s Isp with water, that is only peak Isp, cooling down the nuclear rocket because of decay heat will mean significant propellant lose as lower Isp or just boiling off after it has landed. Nuclear rockets also need to carry a cooling system to deal with the decay heat without constantly boiling off propellant, which means big heavy radiator panels, but this comes at the advantage of being its own power source with each nuclear rocket engine likely providing excess dozen of kw of electric power at all times. Other advantages of nuclear water rockets are that water is dense and easy to store, meaning smaller and insulated tanks. There is an option for getting materials off and on the moon without costing any fuel at all, not even in maneuvering propellant: a bean stalk. Because of the moons low gravity and lack of atmosphere a space elevator made of Kevlar could haul ice from the poles to L, the problem would be the hauling rate: this system ( claims 340 tons a year to L1, but would require thousands of tons of cable and counter weights in cis-lunar space, I calculate that a 100,000 km long ribbon climbed at an average speed of 15 m/s would take 77 days! Considering the mass of each climber is under 1 ton, there is no sane way humans would be transported via this means, cargo though sure.
  13. According to my calculations the hydrogen sulfide in the lunar permafrost would produce 15.7 kg of sulfur per 100 kg of water mined, oxidize that would mean it could store 15.7 of oxygen as SO2, 23.6 kg of oxygen as SO3 and 31.5 kg as SO4! Remember we have an extra 9 kg of oxygen after make proper ratio hydrolox from water and the volatilizes, so the sulfur could easily take it all and then some! Carbon we can store as carbon, nitrogen we can store as NO2 in lunar soil as nitrates, and sulfur we can store as sulfur or any range of SOx in lunar soil as sulfates to consume all extra oxygen. Also I am starting to think against N2O mono-propellant. The most efficient in propellant by mass for maneuvering thruster fuel would be hydrolox, but would have problems if running on liquid oxygen and hydrogen, boil off problems, or limited thrust on gaseous oxygen and hydrogen, which would need to take propellant from the main tanks and vaporize and compress them with electric pumps and heaters. Lets assume hydrolox maneuvering thrusters with Isp of 400 s on a 25 ton space craft, for 50 m/s of maneuvering delta-v that comes to 321 kg of propellant, with N2O at 175 Isp it comes to 739 kg of propellant, an extra 418 kg. But the N2O is a much simpler thruster system, single lines instead of two, no vaporizers or pumps as it is self pressurizing, none the less I doubt that would make up a mass difference of 418 kg, also the hydrolox propellant does not need a whole separated fueling up system as N2O does and having access to the main tanks means a lot more maneuvering delta-v potential.
  14. Well that is another problem, if we are going to extra metals from lunar mining to build actual things, we are going to have a huge excess oxygen problem, I'm thinking of saving nitrogen by reaction of NO2 with lunar soil to form Metal nitrates ([M]O + NO2 -> [M]NO3) I'm starting to think at a certain point we are just going to have to dump oxygen, either that or use it in electric propulsion systems off the moon. The carbon and sulfur are easy enough to store as elemental solid, in piles for future use someday, or not, but not the nitrogen and certainly not the oxygen, only together can as NO2 and then as metal nitrates can oxygen and nitrogen be stored and that is nitrogen limited, which can barely handle the excess oxygen from water processing to hydrolox. We could consider freeing out CO2 in the craters, just open storage of CO2 as dry ice, but I fear it will subliminate, and again not much carbon to work with. SO2 though we could probably freeze in the craters and it probably would not subliminate, yes you are right all the extra sulfur we could store excess oxygen as sulfates! Again I don't think we should burn metal as propellant, it is too energetic to make out of lunar soil anyways, much more useful to make things with it instead. Combined with lunar mining of water and hydrogen sulfide we can store the extra oxygen from reducing metal out of soil as sulfates.