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Simpleχity;1065814935 said:Wishing for a US-Made Heavy Lift Rocket Won’t Make It So
If Congress really wants to ditch Russia’s RD-180 engine, it needs to fund the research — and get ready to wait....
Surprising that no US company can currently supply the thrust-assembly for the Atlas V rocket.
Simpleχity;1065814935 said:Wishing for a US-Made Heavy Lift Rocket Won’t Make It So
If Congress really wants to ditch Russia’s RD-180 engine, it needs to fund the research — and get ready to wait....
Surprising that no US company can currently supply the thrust-assembly for the Atlas V rocket.
What happened to the country that sent men to the moon just twelve years after the Soviets sent up the first satellite?
It's time we got serious about space exploration. Rockets are yesterday's technology, though. Let's work on a new generation shuttle, or, better yet, let's build a space elevator. The materials technology would have so many spinoffs, it would more than pay for the research in the long run.
1. The race to the moon was never about the moon. It was about being able to bomb someone on the other side of the planet.
2. The shuttle was the wrong way to go, I think. Reusability was supposed to be a cost-saver, but the maintenance turnaround was so costly that it ended up more expensive than disposable vehicles. I think a more efficient launch vehicle can be made, perhaps with a partially reusable setup. But the re-entry vehicle I think needs to be a throwaway, the heat and stress from that is what made the shuttle maintenance so expensive.
3. Space elevators would require a material that doesn't exist. There's no reason to even think about a space elevator until some new magic breakthrough in materials happens. Even then, it's a fairly ludicrous undertaking.
1. It was partially about that, but mostly about showing the world that we could do what the godless Commies couldn't. Competition motivated us to go to the moon.
2. That was with old technology. Let's build a new one with 21st. century technology.
The materials don't exist and there's not a really good reason to expect they can exist. Bonding strength of carbon is a known value and even theoretically perfect carbon nanotubes are simply not up to the task even under perfect circumstances. And the circumstances with such a construction would be nowhere near perfect. Wobbles would be unacceptable... and unavoidable.3. Exactly why we should build one. The materials research will prove useful in many different applications. Let's start with carbon nanotubes. Breakthroughs are not magic, they are based on research and experimentation.
The fundamental problems remain. Re-entry is an enormously stressful undertaking, and the tolerance for failure in this phase is essentially zero. Thus, extreme precautions are required to achieve the relatively low failure rate we had. I'm not sure how you can design a machine able to endure this stress and not require thorough maintenance inspections.
The materials don't exist and there's not a really good reason to expect they can exist. Bonding strength of carbon is a known value and even theoretically perfect carbon nanotubes are simply not up to the task even under perfect circumstances. And the circumstances with such a construction would be nowhere near perfect. Wobbles would be unacceptable... and unavoidable.
You need something orders of magnitude better than carbon nanotubes to handle the real stress of the task, and for the moment there's not even anything theoretically capable of that.
And the whole thing would fail in a spectacular and catastrophic fashion when a piece of space junk the size of a thumbnail snaps the tether. That's an awful lot of material to have coming back to earth.
I don't say "never" when it comes to this kind of thing. But this is pretty close.
Same deal with warp drive. I'm not saying it can't be done, but warp drive would require Einstein to be wrong and he doesn't seem to be wrong. And even if the concepts of the Alcubierre drive are possible, the energy requirements are estimated between "so far past 'ludicrous' we don't have a word for it" and "literally impossible because this much energy doesn't exist in the observable universe"
I don't pretend to know a lot about this subject, but when I think of powerful rockets, I think of the Saturn V. Is there some reason that five-engine cluster, or some combination of fewer engines, could not be used to launch heavy payloads? It was reliable enough to take men to the moon, and that was more than 45 years ago.
A space elevator might have the same problem. It's a math problem: a specific length is required to reach geosynchronous altitude. That's an absolute requirement. There is a minimum possible weight of carbon atoms stacked this high. That's an absolute requirement. And carbon bonds are only so strong. Even theoretically perfect carbon nanotubes get yanked apart when subject to the force of their own weight.I'm sure it would be difficult to build a new generation space shuttle, but we did build one that worked at one time. Building a space elevator is even more difficult, but telling people it can't be done should be a challenge to prove the naysayers wrong, and not an end to the attempt. A warp drive, as far as we know, violates the laws of physics.
No. Which is why I don't say "never."Imagine if, 100 years ago or so, someone had declared that I could sit in my living room and communicate in real time with people all over the world, that I could instantly check any facts in dispute via an electronic device that could search through millions of sites in a few seconds, and that I could, if I got tired of such an international bull session, go shopping on the same device and buy anything within reason and have it brought to my door. Would anyone have believed them?
Saturn V was cancelled because Congress stopped funding a trip to Mars and because of the space shuttle. Sad, really.
Yes, it is. When you've already designed, built, and proven a machine which is better than anything else at lifting heavy loads, why not make a few more of them?
Me too.A space elevator might have the same problem. It's a math problem: a specific length is required to reach geosynchronous altitude. That's an absolute requirement. There is a minimum possible weight of carbon atoms stacked this high. That's an absolute requirement. And carbon bonds are only so strong. Even theoretically perfect carbon nanotubes get yanked apart when subject to the force of their own weight.
So we need a new substance. Something even stronger, by a wide margin, before we can even think about the rest of the extremely tall hurdles to cross. Problems like: "what happens if it starts wobbling" and "can it survive a hurricane?"
No. Which is why I don't say "never."
I hope I'm wrong
Me too.
Maybe a space elevator is an impossibility. We'll never know until we try to build one.
No, you can know that without ever trying to actually build a space elevator. Just by doing the math on the materials.
It's not like research into materials with high strength-to-weight ratios just sat around and waited for someone to think up the space elevator concept. Humanity has been doing that ever since we figured out the concept of construction. Hey, Ogg want live on field, not in cave. Ogg want roof. Rock heavy. Stick not heavy. Use stick for roof.
If humanity collectively decides that space elevators are impossible, we're still going to research carbon nanotubes and beyond. And then maybe some day someone will come up with the next level **** that makes people go "hey wait!"
So, materials research is the first step, isn't it?
I totally agree, the Saturn V to me is the greatest rocket ever built. Tremendous payload capability and solid, 100% safety record. It quite simply never failed. The SS was a huge boondoggle that set us back 20-30 years and we're only now starting to catch up.
I think the move towards a reusable vehicle was because of the ever growing amount of space junk in orbit around the earth.
I thought the problem with the Saturn V rocket is we reached a point where any increase in payload required building another rocket because a larger rocket was less efficient.
We need a new and much more efficient propulsion system. While a coal burning steam engine can power a train or a ship it is not efficient enough for a plane or a helicopter. I think we have reached the same problem with space travel.
SS was touted as reusable but it never really was. Saturn V was really a victim of politics and budgets.
As far as a new propulsion system goes, unless we discover the warp drive, rockets will remain as the most efficient way to get stuff up into orbit.
SS was touted as reusable but it never really was.
Saturn V was really a victim of politics and budgets.
As far as a new propulsion system goes, unless we discover the warp drive, rockets will remain as the most efficient way to get stuff up into orbit.
I am very much for space exploration if it is privately funded.
I am TOTALLY against it if it is taxpayer funded (except for purely military applications).
If the masses want to send people to Mars...then let the masses pay for it directly - not through the INCREDIBLY corrupt and inefficient government.
You have veterans living on the streets and tens of millions of Americans on foodstamps and people actually want to spend billions of dollars that the American government does not have to send a few people to Mars? No problem with those priorities. :roll:
Leave Mars to the private sector. And if enough Americans want them to get there, they will. And if they don't, they won't.
Nobody is living on the street because of NASA. Don't give me that tired bull****.
Oh for ****'s sake. We're done here.Not due to NASA directly...DUH.
But are you saying that money that goes to NASA could not assist homeless veterans? Are you seriously that out of touch with reality? Or do you just not care about veterans who risked their lives for their country?
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