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I said almost impossible, considering it is starting from a planet moving through the space with 30 km per second and subject to numerous gravitational influences. You'd have to bring it to a complete standstill in its trajectory around the sun (so to say) and you'd have to correct every gravitational influence (except the one of the sun) accordingly. Everything that moves slower than parabolic velocity will according to the Kepler laws move in an elliptic orbit, in one focus of which the sun is, i.e. it can't reach the sun. It is of course not completely impossible, but it would be quite a challenge to achieve.
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Surely the Sun is wide enough so you don't need to hit it dead on target?Comment
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Well, what would happen if you started a rocket directed at the sun? It moves with the speed given by its engine towards the sun, but at the same time with a speed of 30 km/sec in a perpendicularly different direction (since it would start from the earth orbit). Hence, it would not move towards, the sun, but in some kind of very wide spiral.
As long as it can maintain its own propulsion, it could get closer to the sun. But with the current technology this is hardly possible, you would have to carry too much fuel. As soon as the engines burn out, it would remain at the resulting trajectory, which would likely be an ellipse around the sun.
The only way to reach the sun from the earth orbit would be to start in the opposite direction of the earth movement and reach a speed of 30 km/sec relative to the earth quickly. This would neutralize the initial speed and make it possible to be "sucked in" by the gravity of the sun. Of course other planets and objects would also gravitate. The influence of those you'd have to neutralize with corrections.Comment
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Why not slingshot round Venus or something?Comment
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It could be done if you could direct the thrust of your rocket at the direction of your chosing wrt the rocket structure.Comment
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If the slingshot would work or not I can't say, at the moment I don't see anything what would speak against it.
If you want to achieve it with thrust, I am not sure what you mean by rocket structure, but keep in mind, that you'd have to maintain propulsion over a pretty long time (such a flight would go over months if not years), while all we can hope for to carry at the moment is fuel for a few minutes full thrust and a few corrections.Comment
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This is a funny discussion. FYI, it takes more energy to get to the sun than it does to reach escape velocity. So all things equal, it would be silly to sling your trash toward the sun.I came upon a barroom full of bad Salon pictures in which men with hats on the backs of their heads were wolfing food from a counter. It was the institution of the "free lunch" I had struck. You paid for a drink and got as much as you wanted to eat. For something less than a rupee a day a man can feed himself sumptuously in San Francisco, even though he be a bankrupt. Remember this if ever you are stranded in these parts. ~ Rudyard Kipling, 1891Comment
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So, let's get back to the Soviet emblem on Mars.Originally posted by DanS
This is a funny discussion...Comment
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And let us not forget that when amuricans were taking the flag of their sweetheart ally dictatorship turkey in space in a pr relationship with the slaughteter, a russian with greek roots out of the love of his heart had already taken the greek flag to the moon! or if not the moon (dont remember exactly) to space in general.
true storyComment
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You can do a whole lot with our current technology. Chemical rockets may not be feasible 200 years from now, but they are here and they work. We should be able to whittle down the costs to use this technology a fair amount.Originally posted by KrazyHorse
Listen, the fact is that without something like a space elevator the current model of building everything on the ground and putting it into space is never going to be economical for large-scale industry. You can't burn off 95% of your mass just getting to where you're going and expect things to pay off.
Building **** where the delta-v costs are lower is the obvious way to go.
It's only small-minded thinking that's prevented us from doing this so far...
Further, we're a long ways away from worrying about manufacturing in space for use in space. Right now, the logistics are such that it's not obvious that building where the delta-v costs are lower makes sense. As a generalization, we can assume that at some time in the future, it may make obvious sense. But that might not be the economic reality of space for many hundreds of years.
Lastly, the fact is that modern space structures will not require much in the way of metals. Rather, they will be built with fabric.I came upon a barroom full of bad Salon pictures in which men with hats on the backs of their heads were wolfing food from a counter. It was the institution of the "free lunch" I had struck. You paid for a drink and got as much as you wanted to eat. For something less than a rupee a day a man can feed himself sumptuously in San Francisco, even though he be a bankrupt. Remember this if ever you are stranded in these parts. ~ Rudyard Kipling, 1891Comment
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Because:Originally posted by Sandman
Why not mine it on site and then transfer the ore to Earth orbit, presuming most of the mining is done by robots? Although the robots could be controlled real-time if in Earth orbit.
a) Robots suck compared to human beings when it comes to uncontrolled situations
b) Why the **** break the asteroid into pieces out there if you're going to be bringing it here anyway?
c) A mining operation requires much heavier equipment than a simple tug. You're putting us in a catch 22; we can't afford to mine the asteroids out there until we have a large infrastructure already in place, and we can't afford to put that infrastructure in place until we have asteroids to mine.
We need materials in HEO. We need mining operations up there to get at them. We need people up there to run the mining operations properly. We need factories up there to build spaceships from the materials we get. We need people up there to run those factories. We need orbital farms to feed those people and keep them happily breathing oxygen. We need nuclear power plants to keep the farms and mines and factories running.
Voila. You've got a self-sustaining community.12-17-10 Mohamed Bouazizi NEVER FORGET
Stadtluft Macht Frei
Killing it is the new killing it
Ultima Ratio RegumComment
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It won't ever be the economic reality of space if space exploration continues along the anemic path we've set out for it. We can do this **** in the next twenty years.Originally posted by DanS
You can do a whole lot with our current technology. Chemical rockets may not be feasible 200 years from now, but they are here and they work. We should be able to whittle down the costs to use this technology a fair amount.
Further, we're a long ways away from worrying about manufacturing in space for use in space. Right now, the logistics are such that it's not obvious that building where the delta-v costs are lower makes sense. As a generalization, we can assume that at some time in the future, it may make obvious sense. But that might not be the economic reality of space for many hundreds of years.
Then grab a carbonaceous chondrite asteroid too...Lastly, the fact is that modern space structures will not require much in the way of metals. Rather, they will be built with fabric.12-17-10 Mohamed Bouazizi NEVER FORGET
Stadtluft Macht Frei
Killing it is the new killing it
Ultima Ratio RegumComment
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The reason why it's on this anemic path is because it costs so much money to get out of the gravity well. The reason why it costs so much money is because it's a government operation that isn't meant to lower costs. The reason why it's a government operation is because it cost so much to do this stuff.It won't ever be the economic reality of space if space exploration continues along the anemic path we've set out for it.
I came upon a barroom full of bad Salon pictures in which men with hats on the backs of their heads were wolfing food from a counter. It was the institution of the "free lunch" I had struck. You paid for a drink and got as much as you wanted to eat. For something less than a rupee a day a man can feed himself sumptuously in San Francisco, even though he be a bankrupt. Remember this if ever you are stranded in these parts. ~ Rudyard Kipling, 1891Comment
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Is it the only reason?Originally posted by DanS
The reason why it costs so much money is because it's a government operation that isn't meant to lower costs.
If space was a private entreprise, would exiting the gravaity well be as cheap as taking the car to the local supermarket?"I have been reading up on the universe and have come to the conclusion that the universe is a good thing." -- Dissident
"I never had the need to have a boner." -- Dissident
"I have never cut off my penis when I was upset over a girl." -- DisComment
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No, but it's responsible for at least an order of magnitude of the cost differential.Is it the only reason?I came upon a barroom full of bad Salon pictures in which men with hats on the backs of their heads were wolfing food from a counter. It was the institution of the "free lunch" I had struck. You paid for a drink and got as much as you wanted to eat. For something less than a rupee a day a man can feed himself sumptuously in San Francisco, even though he be a bankrupt. Remember this if ever you are stranded in these parts. ~ Rudyard Kipling, 1891Comment
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