Betruger wrote:The ISS can't be kept in orbit for much longer than the current plan (~2020, right?) for reasons other than resupply (orbital transportation and paying for it) and station keeping, right? If not, what are the other reasons for it, in short?
If I recall correctly, the Russian modules will be nearing end-of-life around that time, and since they are the heart of the station and cannot be swapped out or replaced, any attempt to keep it going past that date would have to involve either using the hardware beyond its design life or
massively rearranging the station on orbit and adding new core modules (which would be
very expensive and difficult, and is probably flat-out impossible without something like Shuttle - you'd be better off just building a new station, and maybe carting over a couple of the newer and less essential modules if you really wanted to keep them).
The international partners want to extend ISS to 2028. I believe this would involve using basically the entire station past its design life, probably with lots of spares/ORUs required, and maybe a few replacement modules or solar panels. I'm also reasonably sure NASA has not yet studied what it would take to do this, since even the requirements for extension to 2020 aren't known yet.
Skipjack wrote:The shuttle programme was ended by the previous administration. So that too was already in motion and unpreventable.
Wrong. Even now, it's not too late for a Shuttle extension. If more than four or five extra flights are required (STS-335 tank, a few part-built tanks, and an old LWT), it would have to fly less frequently for a couple of years while the vendors were brought back on line, but anyone who says Shuttle can't be extended any more, and that it isn't just a matter of funding it ([cough]Garver[/cough]), is either lying or misinformed.
The other problem is that the old plan did not even mean that the ISS would be extended.
Griffin seems to have decided that the ISS was inconvenient to his grand moon plan, and cut it off at the knees. At least we're not planning to splash it early any more...
No, it doesn't.
Main article:
http://en.wikipedia.org/wiki/Research_a ... ce_Station
I'm pretty sure that's mostly what's been going on up to now (ie: squeezed in during construction, with incomplete resources), plus some known near-future work. The behind-the-scenes ramp-up sparked by Obama's "full utilization" plan is quite substantial, from what I hear... admittedly I don't know what all is going on, but just as an example, it seems there are drug companies in talks to try to get around legal obstacles so they can use the ISS...
Another point example (though it was already planned) is VASIMR, which cannot be fully tested on Earth and would be very expensive to test in orbit without a station...
The Alpha Magnetic Spectrometer will be going up. There's been talk of a centrifuge module too, which would be nice because there was supposed to be one but it was grounded...