31–40 of 70 posts
So is infertility in astronauts still a problem? I could be totally wrong, but I was under the impression we haven't solved the problem of increased radiation negatively affecting fertility in both male and female astronauts.
Earlier quoted context omitted.
I don't really see the benefits of space elevators, to be honest. At an altitude of 100km the gravity is still virtually the same. And you still need a huge amount of fuel in order to put your rocket/plane into orbit. Unless you build an elevator with a height of 42'164km (geostationary orbit) - but that seems unrealistic to me.
> "I don't really see the benefits of space elevators, to be honest. At an altitude of 100km the gravity is still virtually the same." You would have made the first 100km of the journey more fuel efficient, is that not a good enough reason?
Earlier quoted context omitted.
If people had waited to leave Europe until the 1970s the culture had been "refactored" enough for the masses, I doubt the world would have advanced as far as it had and the pressure of the population growth from industrialization would have caused some real issues. Actually I think it might be refactored even worse for the masses. Letting the average person go out and build new things helped a lot. Also, do you reall…
Perhaps technology has advanced too fast for the "culture". Perhaps we should design our intentions before we build the tech, and not the other way around. Look at NASA for inspiration on design and forethought.
I was hoping the article would talk about space elevators, and not space planes. I'm eagerly awaiting materials science and geo-politics to mature enough to allow the construction of space elevators. https://en.wikipedia.org/wiki/Space_elevator
The other option would be dropping the cable down, but you'd probably end up with a similar problem. I'm no physicist, but I'm pretty sure that dropping that amount of mass would shift the center of mass of the satellite-cable system and mess with the orbit.
Even if you manage to deploy the cable, you'd still have the problem of the counterweight. I've read that proposed solutions include a captured asteroid (we've just been able to land - or crash, depending on how you see it - in one), a space station/spaceport (that's definitely not cheap), an extended cable (which probably would require even more complex materials) or junk from the construction (still the same problem).
And we still haven't got to the point of security. How do you keep things (space junk, satellites, meteors) from hitting the cable? What would we do if several kilometers of ultra-strong cable fell down into the earth?
I think that space elevators are a nice fantasy, and just that. When we have mature enough materials and geopolitics, we'd probably be better off using them on other methods that seem to be far more viable.
Space planes should absolutely be part of our strategy, but their effectiveness diminishes once you get past LEO. An effective program would have different vehicles for different purposes, using the right tool for each job.
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The problem with this is you're designing based on your current world view and assumptions. When does this type of planning ever work and actually stand up to 20 years of history? 40? 100? In the 50's the us was DESIGNED around the car and suburbs. That worked well.
My logic is based on numbers. Earth Population, Imaginary lines in the sand, War over money. These are not signs of intelligence, especially when they have only 1 planet to survive on that gets more populated every day with little regard to long-term resource management, although I am proud of the Svalbard Global Seed Vault. :) This type of planning worked for Voyager (NASA/JPL). fyi: cars suck. Dirty, inefficient, a…
Earlier quoted context omitted.
Perhaps technology has advanced too fast for the "culture". Perhaps we should design our intentions before we build the tech, and not the other way around. Look at NASA for inspiration on design and forethought.
The problem with this is you're designing based on your current world view and assumptions. When does this type of planning ever work and actually stand up to 20 years of history? 40? 100? In the 50's the us was DESIGNED around the car and suburbs. That worked well.
https://en.wikipedia.org/wiki/Treaty_on_the_Non-Proliferatio...
With a few exceptions, that's been working since the 70's.
Much as I love to cheer for British engineering, I don't understand the logic here. A rocket would require an expensive inspection before reuse but a spaceplane wouldn't? Why? Also not one SABRE engine has even been built yet, whereas SpaceX has got very close to landing their rockets.
SpaceX have landed their rockets. Just not ... in one piece.
I was hoping the article would talk about space elevators, and not space planes. I'm eagerly awaiting materials science and geo-politics to mature enough to allow the construction of space elevators. https://en.wikipedia.org/wiki/Space_elevator
I think the problem with space elevators are not as much with the materials but with the logistics of deploying that. How do you get the cable up there? You can't just shoot up a rocket with a cable attached and expect the cable to stay upright: it would fall down unless you give it horizontal speed. But if you do that, you'd probably end up orbiting the Earth and tying it up with the cable. The other option would be…
Well, actually...
Package your cable up, launch it, move to geosynchronous orbit. Start deploying your cable. Once it gets long enough, say a few kilometres long, tides hold it rigidly pointing towards Earth. You solve the counterweight problem by also extending a cable outwards from your launch vehicle, so keeping the centre of gravity still. Eventually the bottom of the cable reaches ground level and you're done. On the plus side, you now also have a 36,000km long cable extending past geostationary orbit, ideal for interplanetary launches.
> What would we do if several kilometers of ultra-strong cable fell down into the earth?
Not much. If the point at which it's severed is low, the lower part will just fall down and you pick it up and weld it back on. If it's a bit higher, the lower part falls down and burns it. If it's a bit higher still, it goes into orbit.
People have been thinking about the engineering and geometry of space elevators for a long, long time...
I was hoping the article would talk about space elevators, and not space planes. I'm eagerly awaiting materials science and geo-politics to mature enough to allow the construction of space elevators. https://en.wikipedia.org/wiki/Space_elevator
I don't really see the benefits of space elevators, to be honest. At an altitude of 100km the gravity is still virtually the same. And you still need a huge amount of fuel in order to put your rocket/plane into orbit. Unless you build an elevator with a height of 42'164km (geostationary orbit) - but that seems unrealistic to me.