Unfortunately, no participating nation is any longer spending money developing or improving module designs with the exception of changing out the docking systems after Shuttle ends so that all the docking ports would be the same and support the new standard. So when a module fails and it can’t be repaired then that functionality if it is not being performed by another module the capability will be lost. This could completely halt some experiments/projects.jbbrandes":idgr340r said:A major focus of constructing ISS was the gaining of experience in long term space habitation. ISS has barely been completed; calling for it to be retired is akin to buying a computer on Monday and then on Tuesday throwing it away because it is no longer state of the art. Experience must be gained in living and working in space and this includes meeting the challenges of maintaining our environment. In these matters we would do best to follow the lead of our Russian partners who kept the short term Mir station operational far past its original planned lifespan.
What concerns me most, however, is that ISS was designed and constructed with a limited lifespan in mind. The expenditure of money, resources, and yes, life that was invested should have resulted in a station that could be maintained as a whole for a far more indeterminate lifespan; Disguarding modules as they age and become unservicable and replacing them with new; Adding new segments to the whole as new requirements and uses are identified; thus creating a station that starts from an established baseline and grows as demands require it. This is what I understood my ISS tax dollars were buying me.