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Its not stupid and its pretty justified. Nuclear technology is inherently dangerous and several serious accidents have occured because of it. More accidents will happen...
...There are no fail safe Nuclear Technologies and if a serious accident does occur, the consequences can be dire and effect for generations. Boiler explosions don't disperse radioactive particles for miles and irradiate everything so its uninhabitable for centuries.
We should be phasing out Fission and prepare for Fusion power. Fusion reactors will produce far more power and don't suffer the problems of a run away chain reaction that causes a meltdown.
It is very likely that Fusion power will be achieved by the time colonizing outerspace is even possible.
Nonsense, no technology is completely 100% fail safe, not cars, airplanes, chemical factories, buildings, medicine, food, none of them are completely safe! It is not possible to achieve 100% safety from anything, thats irrational and silly.
There is a finite, nonzero chance that you will be killed by a falling meteor before you finish reading this post. Its a definite risk. Or a tsunami. Or a or any number of things. But we don't live in caves do we? Its because some risk is acceptable, and well developed nuclear power plants are so safe that their risk is essentially no higher than any other big power plant.
Its time people stopped being irrational, childish fools and accepted the concept of non-zero risk and started acting like adults. With sufficient development, nuclear fission reactors are safe.
Now fusion power, we thought it would be 20 years until we got it to work about twenty years ago... but more importantly, even if we do get it to work on the ground by the time we are ready to start real expansion, is decades away from being a compact, light weight, and efficient power plant for space use. Its easy to make a nuclear fission reactor smaller, increase fuel enrichment and neutron reflector, but a fusion reactor is much more difficult as the bigger they are the more efficient they become.
Eh, Russia tooting its horn to steal NASA's thunder. Note how the dates coincide with NASA's rockets.
If we're thinking colonization, no "big dumb booster" launch vehicle will be cheap or safe enough. A true RLV like the Saenger-II or X-30 NASP is the only current option.
Don't gloss over propulsion when we do get the people up there, simple chemical rockets don't have the efficiency to keep transit times low enough for an average person to stay in good shape physically or mentally. A gas core nuclear rocket would be a nice option, with high efficiency and high thrust with a minimum of radically new technology. It would also give abort-to-port capabilities in the event of trouble.
People are generally pretty scared of being irradiated, nuclear accidents etc.
If my figures are correct on this, It takes around 5-6 months to get to Mars with current chemical rocket technology. People have stayed on the ISS for that long, so it can be done without too much mental or physical damage.
It can be done, but it shouldn't be done, nor is it necessary. And people need to get over their fear of nuclear energy, their fear is unjustified and stupid. Stupid people probably won't take the risk of a Mars flight nuclear or no.
what about using an ION engine? The consumption of fuel would make the venture to Mars less costly then other forms of propulsion. The only question is will the engine provide enough thrust to propell the ship to Mars in a feasible amount of time?
No, it won't.
And the best fuel for ion engines - Xenon gas or Cesium metal, aren't available anywhere in the solar system in sufficient quantity to sustain large-scale ion drive operations.
I would suggest a fission fragment rocket in which Uranium/NILFiR fuel is magnetically suspended outside the back of the spacecraft. There will be a sail, to rebound all of the particles going towards the spacecraft. Isp 30,000,000. It can accellerate 500 MT at 1 G with a 5 MWt reactor.
Five hundred metric tonnes at 1G with a five megawatt reactor? Nonsense, thats a huge acceleration from such a small amount of power.
If we're thinking colonization, no "big dumb booster" launch vehicle will be cheap or safe enough. A true RLV like the Saenger-II or X-30 NASP is the only current option.
Don't gloss over propulsion when we do get the people up there, simple chemical rockets don't have the efficiency to keep transit times low enough for an average person to stay in good shape physically or mentally. A gas core nuclear rocket would be a nice option, with high efficiency and high thrust with a minimum of radically new technology. It would also give abort-to-port capabilities in the event of trouble.
The energetics say it all. Launching from the equator of a 1 km radius asteroid with a rotation period of 10 hours gives a velocity boost of 0.62 kms/hr.
IE not very much.
An idea from an old mid 90's paper, by some folks on the Mining side of things.
http://www.annalsnyas.org/cgi/content/a … /822/1/511
Basically, most asteroids have spin to them. You put a tether down in the main mass, and you send the stuff you want to keep down the tether. Calculate when you need to release it to sling it toward Earth, and you have a velocity boost requiring very little reaction mass.
There is lots of other stuff in the paper, but I found that particularly useful from an economic point of view.
Nonsense, the technology to mine in space will be radically different than on the ground, and you can't aim a tether even if it were long enough to give much of a boost, which it probably isn't. I also bet you would have trouble keeping the thing taught.
WHAT!?!?! You think it will take 93 yrs to develop enough???!?!?!?
To cut up a megaton asteroid and to safely deliver the pieces to the Earth's surface? Yes.
I agree with cIclops, 93 years is probably about right, barring some Kurzweilian singularity.
I'm thinking a combination of compressed Martian air with electrostatic removal, and perhaps even a water shower for the suit.
This non-potable water would be recycled through a grating in the floor and filtered out, and could serve as an emergency backup water supply.
Its not that big of a deal.
*Cough* Chief scientist? As in, the people who say "forget sending man, lets just send robots!" A pox be upon him!
Perhaps a structurally modified Ares-I core with flyback boosters on the side instead of pushing from the end.
Cool, flyback boosters... took long enough.
Though you'd need more than two of them probably, given how powerful the big five-segment booster is... that would take radical redesign of the first stage and launch pad.
Making an intermediate-sized booster with a pair of these on a new core though for Lunar crew or Moon/Mars medium cargo, that would be awesome.
Well above 3000K.
Lunar ceramics/glasses might not have to be THAT strong, remember that gravity is pretty weak.
Silicon nanowire electrode Lithium ion battery powered plugin hybrids, with serial motor arrangement (motor as generator only).
Powered by Generation III+/IV nuclear reactors burning recycled-from-spent-rods MOX fuel and/or Thorium in addition to U-235.
Thats an awful lot of oxygen and silicon
Any particular reason you picked this blend?
Unless they are planning to use Hypergolics, such a platform would probably need a cryogenic condenser... which would be very handy for NASA. Or they might use supercooled Oxygen/Methane rockets, which are storeable with little or no boiloff for months to maybe a year or two.
I think the only practicable application for this would be an H2/O2 torch, and then a portable torch would be infinitely less heavy if you just used bottled gases made from electrolysis.
Considering how they said "RF energy" like it was something magical, I have a bad feeling its a cold fusion wannabe... "power your car with water!" blah blah blah.
But no discussions regarding uniqueness of the process which, unlike electrolysis, produces hydrogen and oxygen together on demand--which could actually be combusted on Mars in the atmosphere outside of the habitats, and used for smelting
Well yeah it is unique, but that doesn't change the fact that its a stupid waste of energy. Who cares if it produces H2/O2 "on demand?" You would get more heat feeding a bunch of resistance or inductance coils then a bank of high-powered microwaves to split water to turn right back around and burn it.
And remember, the mixture is far too flammable to do anything with, including separate. Besides, you aren't going to go wasting precious Martian water even if it were more efficient, instead sticking with direct heating.
The Russians don't even have Angara yet... they seem to be arranging their future spaceflight program over assembling a bunch of light-to-medium payloads in LEO.
Uh no
It takes more energy to break the water down into H2 and O2 than you get from H2/O2 burning. You can't "burn" only water. I can give you math to prove my point if you want.
These "RF photons" are just high-powered microwaves, which by the way, the sun does not produce. You are better off using the electricity directly than breaking down water only to immediately recombine it.
And before you ask, no, you can't bottle a mixture of Hydrogen and Oxygen without too high a risk of it blowing up.
Telling: despite all the flak he's received, he only stops when he's not allowed to grandstand and advertise his website.
I think we can assume deadly spinning would occur because of the high thrust required by the LAS motors; they are, after all, designed to push the entire mass of the capsule very fast aren't they? I believe the risk is so significant that we shouldn't even bother testing it.
Oh, and the LAS attitude control thrusters, if those have to rise on the Orion capsule, then even if they were light weight will severely impact the capsules' mass, since they would have to be carried to orbit and back down to the ground.
add LAS thrusters doesn't change so much the mass saving since great part of the LAS wheigt come from its motor and big structure
I'm not talking about their mass, the attitude control jets on the Orion capsule simply can't produce enough thrust to guide the capsule if you use any sort of LAS system. You need something that is at least a substantial fraction of the LAS acceleration to be able to orient or correct the trajectory, and puny little tens-of-pounds thrust jets presently called for just can't do it.
How much more are those going to weigh? And where are you going to cram those in on the densely-packed Orion capsule?