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Jens
2005-Aug-02, 02:18 PM
I was thinking, wouldn't it be a good idea to develop some kind of orbital craft that would be docked to the ISS, and could fly around in orbit to fix various satellites, etc.? I guess the difficulty would be getting it into orbit, but once you did that, it would make things so much easier.

In fact, though I'm not an engineer, I have an idea for the space program. First, help the Russians with their big rockets, and basically launch large pieces of equipment using their rockets. Second, NASA could work to develop a safe crew module, that could reliably move people into space. And third, develop an orbital craft that could move around in orbit.

NEOWatcher
2005-Aug-02, 02:31 PM
I was thinking, wouldn't it be a good idea to develop some kind of orbital craft that would be docked to the ISS, and could fly around in orbit to fix various satellites, etc.? I guess the difficulty would be getting it into orbit, but once you did that, it would make things so much easier.

In fact, though I'm not an engineer, I have an idea for the space program. First, help the Russians with their big rockets, and basically launch large pieces of equipment using their rockets. Second, NASA could work to develop a safe crew module, that could reliably move people into space. And third, develop an orbital craft that could move around in orbit.
The problem is the fuel usage or maneuvering difficulty to get the craft from an ISS orbit into the target orbit. Orbits are not conveniently parallel. Don't forget, at launch, a mission is already heading into it's intended orbit. That's one of the reasons that there are such small launch windows.

Jens
2005-Aug-02, 02:50 PM
Sure, that's an issue, but I think the solution would be to launch unmanned missions loaded with fuel tanks that could be sent into orbit. If the launch fails, it's a bummer because you've wasted a load of fuel, but at least it wouldn't involve any human lives.

NEOWatcher
2005-Aug-02, 04:22 PM
Sure, that's an issue, but I think the solution would be to launch unmanned missions loaded with fuel tanks that could be sent into orbit. If the launch fails, it's a bummer because you've wasted a load of fuel, but at least it wouldn't involve any human lives.
But what advantage is to have all that fuel in orbit vs just shooting something into the desired orbit. You've reduced the fuel usage not only by the amount of fuel shot into orbit, but also by the amount of fuel used to shoot that fuel into orbit. So by parking the unmanned mission on earth, you don't even waste the added fuel
You also still need to get those astronauts there in the first place. So you haven't eliminated the problem. You've just shifted a few of the problems.
I personally don't think that a launch is the real issue anyway. It's the complexity of the re-entry that causes the problems. It's those re-entry materials being damaged.

Ara Pacis
2005-Aug-02, 04:51 PM
Sure, that's an issue, but I think the solution would be to launch unmanned missions loaded with fuel tanks that could be sent into orbit. If the launch fails, it's a bummer because you've wasted a load of fuel, but at least it wouldn't involve any human lives.
But what advantage is to have all that fuel in orbit vs just shooting something into the desired orbit. You've reduced the fuel usage not only by the amount of fuel shot into orbit, but also by the amount of fuel used to shoot that fuel into orbit. So by parking the unmanned mission on earth, you don't even waste the added fuel
You also still need to get those astronauts there in the first place. So you haven't eliminated the problem. You've just shifted a few of the problems.
I personally don't think that a launch is the real issue anyway. It's the complexity of the re-entry that causes the problems. It's those re-entry materials being damaged.

I've read that fuel is one of the cheapest components of a launch system.

Captain Kidd
2005-Aug-02, 05:24 PM
I've read that fuel is one of the cheapest components of a launch system.
But it has weight, which requires more fuel to lift to orbit. And that extra fuel means even more fuel needed.

So it becomes a question of cost to benefit.

Which is cheaper?
A) The costs of keeping people in orbit supplied with living necessities, parts for all the various satellites and I bet no two share anywhere near the same components, crafts, fuel, most of which are used up and require replacement

or

b) Just put a replacement satellite into orbit costing only one launch when the original breaks down.