Seems a shame to dump 460 tons of space station in the Pacific. If they want to test a large xenon/argon drive system powered by big solar arrays, boosting the ISS out to L1 would seem to be an ideal opportunity, while preserving an important historical artifact for future generations, while getting some data on the L1 environment.
I want to hear more about this from you alpha nerds.
Testing testing. The main page shows 2 comments on this thread, consistently, while the thread itself showed just one, consistently. It was occasionally doing that prior to the new format, so I’d say the issue is something other than whatever has been changed.
Yeah, I’ve also been seeing “phantom comments” lately.
Hrm…. The main page shows four comments but the thread just shows three, consistently.
Anyway, to keep this comment from being “can you hear me now?”, I’m thinking of doing an experiment toward a turbopump with no moving parts using a water jet (as from a lawn sprinkler) propelled by the exhaust from an Estes rocket motor diagonally downward into a cylinder, where the water should spin downward in a violent vortex to separate the descending liquid from the gas exhaust stream, which is ported out the top. I tried a simpler experiment of just blasting water from my hose diagonally downward into a drinking glass and it spun up fine, acting as a cyclone separator and maintaining a very high angular velocity. The next step is to have the bottom of the glass ported into a standard or double-volute for pressure recovery.
Having crunched lots of math on the turbine and impeller of a conventional turbopump, the efficiency of one without the moving parts shouldn’t be significantly less if the burner motor (a thruster) has a high exhaust velocity. If you eliminate all the moving parts of a turbopump, you eliminate almost all the cost, and thus most of the cost of a rocket engine, and thus most of the cost of a rocket. The question is will it work right, kind of like the question on this blog’s comment section. ^_^
Hrm… Main page shows eight replies, comment page showing five, so it’s not an off-by-one error.
I think this is a issue that the ISS itself will decide. If it continues to function well then it makes sense to keep it in orbit beyond 2020.
However if problems develop that are non-fixable without the Space Shuttle, like needing to replace the solar arrays, then the ISS partners may have no option other then to deorbit it before it becomes a hazard, like “Skylab”.
Moving it to the EM L1 sounds like a good idea (although EM L4/EM L5 would be more stable if storing it) and if NASA is able to move a 500 ton NEO they should be able to move a 1,000 ton ISS. But the key question would be if the ISS electronics are “rad harden” enough to survive in that environment.
You wouldn’t need a Shuttle flight to replace a solar array. I could come up with a way to do it for a couple hundred million, using F-H and a Dragon in blow-down mode. Or even just based out of ISS, using the station’s arm.
Rand,
In theory, but the key point is that until we see the different technical issues that emerge as the ISS ages, the jury is out if they will be repairable with the capabilities we have now or in the foreseeable future. Perhaps the fixed you mention will work for the solar array, perhaps it won’t. But until something actually fails we are just guessing.
Also I meant to say 460 ton ISS, not 1,000 tom.
Oops, by L1, I meant L4 or L5.
They should also probably add some redundancy to the cooling system, and perhaps add spare solar panels.
To be useful outside LEO, they’d need to add at least one small habitation module with significant radiation shielding, so any visitors could shelter in place during a particle event. Such a shelter serving as sleeping quarters and as a general work station would also roughly halve the amount of daily radiation any crew experiences, and serve as a platform for evaluating long-duration Mars missions. It would squeeze a little more utility out of an aging but extremely expensive facility, and provide a destination beyond LEO that’s reachable by the current and planned generation of capsules, without requiring the next step to include the mass and complexity required for lunar missions, while perhaps serving as a stepping stone to that very destination.
However if problems develop that are non-fixable without the Space Shuttle, like needing to replace the solar arrays, then the ISS partners may have no option other then to deorbit it before it becomes a hazard, like “Skylab”.
Incorrect, the USOS Solar Arrays only provide attitude control via the CMG’s. The CMG’s are not the only means of attitude control. They are only the means for micro-gravity attitude control. If the USOS solar arrays or CMG’s fail to maintain control, which actually has happened in the past; then the Russian segment has propulsive capabilities to regain attitude control. So long as the Russian segment can maintain attitude control, then the ISS can be deorbited with positive control.
What is needed for the Russian segment to conduct such a controlled deorbit? A Progress module will work.
That is the problem with providing an example. Engineers try to fix the one example rather then looking beyond to the point, namely that the ISS, like all hardware, has failure modes that may not be fixable without a Shuttle Orbiter and its tool kit. And when one of those occurs it is finished just as Skylab was doomed once the Saturn/Apollo were retired.
So, I noted originally, the ISS will probably be the deciding factor in terms of how long it is in orbit. If it continues to function, with failures being fixable, it will likely stay in service. It is only when something breaks that is not fixable that will result in it “sleeping with the fishies” to avoid it becoming a hazard.
There is nothing on the ISS that cannot be repaired without the “Shuttle and its toolkit.”
ISS’s purpose: generously, practice.
Learning what not to do is Evolution incarnate.
RE: Evolution
The ability to reproduce preceded the ability of intelligence.
Seems a shame to dump 460 tons of space station in the Pacific. If they want to test a large xenon/argon drive system powered by big solar arrays, boosting the ISS out to L1 would seem to be an ideal opportunity, while preserving an important historical artifact for future generations, while getting some data on the L1 environment.
I want to hear more about this from you alpha nerds.
Testing testing. The main page shows 2 comments on this thread, consistently, while the thread itself showed just one, consistently. It was occasionally doing that prior to the new format, so I’d say the issue is something other than whatever has been changed.
Yeah, I’ve also been seeing “phantom comments” lately.
Hrm…. The main page shows four comments but the thread just shows three, consistently.
Anyway, to keep this comment from being “can you hear me now?”, I’m thinking of doing an experiment toward a turbopump with no moving parts using a water jet (as from a lawn sprinkler) propelled by the exhaust from an Estes rocket motor diagonally downward into a cylinder, where the water should spin downward in a violent vortex to separate the descending liquid from the gas exhaust stream, which is ported out the top. I tried a simpler experiment of just blasting water from my hose diagonally downward into a drinking glass and it spun up fine, acting as a cyclone separator and maintaining a very high angular velocity. The next step is to have the bottom of the glass ported into a standard or double-volute for pressure recovery.
Having crunched lots of math on the turbine and impeller of a conventional turbopump, the efficiency of one without the moving parts shouldn’t be significantly less if the burner motor (a thruster) has a high exhaust velocity. If you eliminate all the moving parts of a turbopump, you eliminate almost all the cost, and thus most of the cost of a rocket engine, and thus most of the cost of a rocket. The question is will it work right, kind of like the question on this blog’s comment section. ^_^
Hrm… Main page shows eight replies, comment page showing five, so it’s not an off-by-one error.
I think this is a issue that the ISS itself will decide. If it continues to function well then it makes sense to keep it in orbit beyond 2020.
However if problems develop that are non-fixable without the Space Shuttle, like needing to replace the solar arrays, then the ISS partners may have no option other then to deorbit it before it becomes a hazard, like “Skylab”.
Moving it to the EM L1 sounds like a good idea (although EM L4/EM L5 would be more stable if storing it) and if NASA is able to move a 500 ton NEO they should be able to move a 1,000 ton ISS. But the key question would be if the ISS electronics are “rad harden” enough to survive in that environment.
You wouldn’t need a Shuttle flight to replace a solar array. I could come up with a way to do it for a couple hundred million, using F-H and a Dragon in blow-down mode. Or even just based out of ISS, using the station’s arm.
Rand,
In theory, but the key point is that until we see the different technical issues that emerge as the ISS ages, the jury is out if they will be repairable with the capabilities we have now or in the foreseeable future. Perhaps the fixed you mention will work for the solar array, perhaps it won’t. But until something actually fails we are just guessing.
Also I meant to say 460 ton ISS, not 1,000 tom.
Oops, by L1, I meant L4 or L5.
They should also probably add some redundancy to the cooling system, and perhaps add spare solar panels.
To be useful outside LEO, they’d need to add at least one small habitation module with significant radiation shielding, so any visitors could shelter in place during a particle event. Such a shelter serving as sleeping quarters and as a general work station would also roughly halve the amount of daily radiation any crew experiences, and serve as a platform for evaluating long-duration Mars missions. It would squeeze a little more utility out of an aging but extremely expensive facility, and provide a destination beyond LEO that’s reachable by the current and planned generation of capsules, without requiring the next step to include the mass and complexity required for lunar missions, while perhaps serving as a stepping stone to that very destination.
However if problems develop that are non-fixable without the Space Shuttle, like needing to replace the solar arrays, then the ISS partners may have no option other then to deorbit it before it becomes a hazard, like “Skylab”.
Incorrect, the USOS Solar Arrays only provide attitude control via the CMG’s. The CMG’s are not the only means of attitude control. They are only the means for micro-gravity attitude control. If the USOS solar arrays or CMG’s fail to maintain control, which actually has happened in the past; then the Russian segment has propulsive capabilities to regain attitude control. So long as the Russian segment can maintain attitude control, then the ISS can be deorbited with positive control.
What is needed for the Russian segment to conduct such a controlled deorbit? A Progress module will work.
That is the problem with providing an example. Engineers try to fix the one example rather then looking beyond to the point, namely that the ISS, like all hardware, has failure modes that may not be fixable without a Shuttle Orbiter and its tool kit. And when one of those occurs it is finished just as Skylab was doomed once the Saturn/Apollo were retired.
So, I noted originally, the ISS will probably be the deciding factor in terms of how long it is in orbit. If it continues to function, with failures being fixable, it will likely stay in service. It is only when something breaks that is not fixable that will result in it “sleeping with the fishies” to avoid it becoming a hazard.
There is nothing on the ISS that cannot be repaired without the “Shuttle and its toolkit.”
ISS’s purpose: generously, practice.
Learning what not to do is Evolution incarnate.
RE: Evolution
The ability to reproduce preceded the ability of intelligence.