Question Space station use beyond the stated date for deorbit

[richfororbit]

So with the space station stated for a deorbit in about decade, would keeping it up there be more beneficial?

The expeditions are doing some good science up there, I admit I'm not focused on it that much, of course the recent news about growing some plants was interesting, eventually more vegatables will be grown. I know growing a plant took place on the old Mir station, quite sometime ago now.

The agency's focus now being on the Asteroid mission if the Space system and Orion are on scheduled.

I have watched a Augustine report clip and having listened to the talk members there, the flexible path meant a asteroid mission with the ultimate goal of Mars.

Of course none mentioned the one off mission of a return to the Moon. Just listening to the budget problem in that clip, nothing further will get done at anytime.

We all just have to feel that the direct mission will take place for the least beyond the missions of getting a working rocket and crew craft.

 

[Thunder Chicken]

By that point the Zarya and Unity will have been in space for 28 years. Mir was up there for only 14 years and was definitely feeling her age when she was deorbited. At some point these modules won't be spaceworthy, or even safe. What is the safe lifetime of an orbiting vehicle? I am not sure anyone knows.

Sadly there are a lot of relatively young components on the station, but the core modules with basic life support, power, and propulsion functions are old. Keeping it flying for much longer would require new core modules and a rather complex disassembly/reassembly.

---------- Post added at 08:12 PM ---------- Previous post was at 07:47 PM ----------

For the occasional investment and launch of a new module the ISS could potentially fly forever, though it would certainly evolve as a system.

However, the ISS has a PR problem in that, while they are doing vital and very useful research on how to operate sustainably in the long term in space, growing lettuce and zinnias in space isn't calculated to ooh and aah the masses. Never mind that those experiments will enable human exploration into deep space - it just doesn't sound cool to the here and now taxpayers.

 

[Lmoy]

Sadly there are a lot of relatively young components on the station, but the core modules with basic life support, power, and propulsion functions are old. Keeping it flying for much longer would require new core modules and a rather complex disassembly/reassembly.

The question here then becomes whether it would cost more to build a new modernised space station, or to replace the core modules of the current one. I'm not a space station engineer, but I imagine since (assuming you want to still have a space station) you'd have to reconstruct everything anyway, you might as well save the cost of launching whatever bits you can save.

 

[richfororbit]

Without a station there won't be anymore orbital experiments. What ever private spacecraft are built and maintained will fill that change once it is gone.

 

[Urwumpe]

Sadly there are a lot of relatively young components on the station, but the core modules with basic life support, power, and propulsion functions are old. Keeping it flying for much longer would require new core modules and a rather complex disassembly/reassembly.

Not that old - most really important modules are on the USOS now and the oldest modules have less load or are often even shutdown for ever. And the USOS systems can be repaired better by EVA/IVA than the Russian ones, because of a more modular design. The core modules have only one function that needs to work for all eternity and that is the pressure hull.

Theoretically, it should be possible to let the modules passively in space for 50 years. Assuming everything that is active on the space station can be repaired and critical systems are replaced as they fail. Like being able to replace a CMG after it failed. Or get a new solar array into space. At one point seals will be corroded and MMOD impacts will have caused permanent damage beyond the replaceable shields. Also tear and wear will also be caused by swapping modules, rerouting cables, etc. But it should be possible.

It all depends on how much science per maintenance are you willed to accept... if you see the ISS as astronautic experiment, it doesn't matter if you are eventually spending more time fixing things than doing research there. Learning fixing things in space is profit enough.

 

[Andy44]

It might be a worthwhile experiment just to learn how to clean and maintain a really old space facility. Disinfect it, repair all the stuff you thought you'd never have to fix, learn to keep what you have, since every gram of mass in space is hard to replace. It's the kind of thing you need to learn before committing to months or years away from LEO, anyway, might as well get started.

 

[Thunder Chicken]

It would be like your first beater car. You get to see all the ways a car can fail and get an opportunity to learn how to fix and maintain them.

So long as it can be done safely, this is a great training asset.

 

[Sky Captain]

ISS also is a lot of metal already in orbit. At some point in the future it may be profitable to recycle it (and probably lot of other big chunks of junk) into something usable.

 

[richfororbit]

I have been re-reading through briefly Aldrin's book on his vision, skimming through in a chapter about testing inflatable modules on the station for use on the Moon in the future.

Of course none of that has happened yet in that configuration.

Since this topic is about the future, as that is an interesting idea.

So far Orbital sciences has only completed one of eight cargo missions to the station. The cygnus module.

This is mentioned also in the book dated from 2011-2012 writing and the plublications two and a half years back.

I think the rocket will get to orbit, and a MPCV, but his Moon vision and certainly the Mars vision by 2035 seems more like 2065.

 

[DaveS]

So far Orbital sciences has only completed one of eight cargo missions to the station. The cygnus module.

Actually, the Orbital ATK has completed 2 Cygnus missions, with the third one currently in progress, unberthing scheduled for Feb. 19. All the cargo unloading has been completed and trash loading is complete.

 

[richfororbit]

I got that info via Wikipedia.

Aldrin mentioned in 2013 that the first would take place with eight more, in total at some point.

 

[Admiral_Ritt]

In addition to critical modules' internal workings wearing out...

My impression was the other chief concerns about keeping the
station operational were: over a 20+ life span

1) the hull structure it self taking the punishment of micro meteor strikes

2) heating and cooling cycle due to day night cycle in orbit.

But: Wasn't there a way to mitigate both 1 and 2, BY:

Installing a solar shield with the thickness to annihilate MOST
micro meteorites BEFORE they impact the main hull?

It's too late now, the damage is done, but I am surprised no one
thought to try and do this earlier in the ISS program.

As for the key modules wearing out, if the station was better preserved
you might use new modules and bypass the old ones.

I don't know if the backbone supporting the solar arrays can be protected
or even if they are exposed to same degree at the modules.

 

[Lmoy]

It's too late now, the damage is done, but I am surprised no one
thought to try and do this earlier in the ISS program.

The ISS modules do have micrometeorite shielding, but that kind of stuff still wears out over time.

My main worry if the ISS program is ended and the station is deobited is that we'll never get a replacement, and no further progress will be made, just like Apollo. But at the very least, it looks like private corporations are going to pick up the space station slack with their space hotels.

 

[richfororbit]

The ISS modules do have micrometeorite shielding, but that kind of stuff still wears out over time.

My main worry if the ISS program is ended and the station is deobited is that we'll never get a replacement, and no further progress will be made, just like Apollo. But at the very least, it looks like private corporations are going to pick up the space station slack with their space hotels.

Is there a company you know of wanting to do that?

I only know of Galactic's near orbit tourism. Space tourism in orbit is never mentioned in the press. I think that is still a while away.

 

[PhantomCruiser]

http://bigelowaerospace.com/bigelow-aerospace-spacecraft/genesis/

Two test beds have already been launched. The 3rd would have been much bigger. IIRC, it was cancelled because they'd determined they had enough lessons learned to begin on the B330. The BEAM can only add to the lesson pile.

 

[Artlav]

It would be like your first beater car. You get to see all the ways a car can fail and get an opportunity to learn how to fix and maintain them.

I was under the impression that Mir was just that?
At least "Off the planet" gave that impression.

 

[Fabri91]

Well, yes, and I imagine that lessons learned from the Mir also helped the ISS score markedly better in important metrics such as "not being on fire" and "not being rammed".

 

[Andy44]

The longevity of both Mir and ISS taught lessons about things like bacteria and moisture in a freefall environment that are useful. There was a story a few years go about a wall panel that had globules of disgusting water sticking to the back of it that were basically breeding grounds for bacteria. The moisture was from the breath of the astronauts over the years IIRC.

 

[Mafo]

There was a story a few years go about a wall panel that had globules of disgusting water sticking to the back of it that were basically breeding grounds for bacteria.

Dug up the story possibly: http://science.nasa.gov/science-news/science-at-nasa/2007/11may_locad3/

Oddly, I couldn't find any further information on what's used these days, I assume something else since this page indicates LOCAD-PTS was only in use 2006-2009: http://www.nasa.gov/mission_pages/station/research/experiments/232.html

Further reading:
https://en.wikipedia.org/wiki/LOCAD

 

[Urwumpe]

Well, Mir had a permanent crew of 3.

The ISS is four times larger than Mir and has a permanent crew of 6.

Will the successor of the ISS be 4 times larger than the ISS and have a permanent crew of 12?