My suspicion is that this is a little like modern cars. Once upon a time you could, and did, drive your car through quite deep fords (I'm not sure we have any left now on public roads. And they really could be quite deep sometimes. But there was very little to go wrong. Now, you go through a puddle a bit quick and you're liable to blow the electronics. The more sophistication in our technology, the more chances there are for failure.
Yes, there is some truth to this. Most of our progress in the last 50 years has been in certain fields; micro electronics (ie computing) and arguably bio tech. But getting to the Moon (or even Mars) remains a huge electro-mechanical challenge. And those two fields of knowledge (electrical engineering and mechanical engineering) are just about done. I mean our discoveries and progress in those areas are complete and finished. Same soon for chemical engineering. The old assumption that we would continue to advance technologically in an almost linear fashion was very much mistaken. This is the reason we are not going to Mars (and never will). What was impossible 50 years ago remains impossible for the exact same reasons. At this point, I'd be happy if we can just hold on to our existing levels of knowledge and understanding. Unfortunately there are very real signs of regression.
That wouldn't be your entire fuel capacity, just your reserve. But you could circulate it with the rest of the fuel, use it for cooling or make it part of the astronauts "hydration cycle". The point is it would not be dead weight but something useful.
We could have gone to Mars 50 years ago - just not with chemical rockets. That is an artificial impediment.
Don't forget, also, the amount of reaction mass required to move the payload; the rocket, crew and cargo. That reaction mass is frequently just the spent fuel but as we move towards nuclear drives then they need a reaction mass to expel to give the thrust. You can have all the energy in the solar system but be unable to move if you don't have reaction mass.
I wasn't neglecting the reaction mass, I was saying that non-chemical motors use reaction mass much more efficiently because they might dip into our friend E=MC^2. If you had perfect efficiency the difference is 100,000 to 1.
You miss my point if you convert all the mass to energy (E=MC^2) then you go nowhere. The energy alone will do nothing except maybe make you rather hot. But if that energy is used to eject mass then you have to have reaction mass, nothing to do with the energy used in the nuclear reaction (E=MC^2), which only states how much energy is contained within mass.
I didn't miss the point. If you use a nuclear reaction to excite and eject reaction mass, the mass is going to be moving at a much higher rate than if you used a chemical reaction. Which is why a ship that is moved by detonating small nuclear bombs (1950s Orion) can carry a very small ratio of fuel weight to ship weight than a chemical rocket, yet achieve much higher velocity and range.
This was your original statement. It misses the concept of reaction mass (note that is not the same 'reaction' as a nuclear reaction). It doesn't matter whether it is a chemical explosion or nuclear, that is just the energy part. Then you use that energy to eject mass, that's the reaction mass part. Completely separate to the mass of the vehicle. The nuclear reaction converts a very small amount of mass very efficiently into a large amount of energy. But that small amount of mass cannot move your vehicle as it is now pure energy ie. massless. So you need additional mass, reaction mass, to actually propel your vehicle. The E=MC^2 has no meaning for that mass all that matters is momentum; how much mass and how fast it is expelled.
My posts must confuse you because you think that a nuclear reaction is massless or something. But a proton ejected from a nuclear detonation has mass and velocity, and if that velocity is thousands of times what a chemical reaction can do, then it's momentum is thousands of times as much.
I don't believe this is an issue at all. A small motor fired for a long time produces similar crossing time results to a large motor fired briefly. No power source we know of will produce 1G or more for longer than hours.
Not really any closer to the Moon. We don't have a viable rocket like the Saturn V. No orbiter and no lander. Do we even have a valid space suit for the surface? So much work to be done.
Unless a miracle happens in the next four days, either we should close this thread...
There's a race on between the Scots and the Indians to put either the spacekilt or spacesari on the moon first.
The Chinese are working on an interesting way of getting to the Moon. Instead of putting everything into one super ship and going to the Moon from Earth and then back to Earth they plan on using their space station as a staging location for their lunar mission. A couple of trips up to the station to get everything organized. Then a trip to the Moon, then back to the station again. It sounds practical.
Odds on the Chinese are going to get there next. No doubt in my mind.
