Barring a catastrophic malfunction or damaging impacts from space debris, NASA should be able to keep the International Space Station (ISS) in operation at least through 2020 and, with steady funding, careful planning and a bit of luck, through 2028 -- the 30th anniversary of the first module's launch -- officials say.

But reduced power from degraded solar arrays and other crippling consequences of decades spent in the extreme environment of space will slowly but surely take their toll and the cost-benefit ratio eventually will tilt in favor of abandonment and a fiery controlled re-entry.

The International Space Station.

While the engineering and management challenges associated with keeping the station operational are daunting, ISS program manager Michael Suffredini says they should be doable, as long as NASA has the resources to build spare parts, pay for cargo launches and provide transportation for U.S. astronauts, either aboard U.S. commercial spacecraft or Russian Soyuz capsules.

"We have a space station that is designed in a modular fashion meant for repair," Suffredini told CBS News. "So as long as you have spares for all the things that can break, you can last as long as the structure will let you last. Within reason.

"The structure, it turns out, most of it was originally designed for 30 years. So all that margin has made it relatively easy for us to get to 2020. 2028 will be a little bit more challenging. ... We may have to sharpen our pencils to get to 2028."

Boeing, NASA's space station prime contractor, is currently conducting a detailed engineering analysis to verify that the U.S. segment of the complex can safely operate through the end of the decade. Russian engineers are assessing their own hardware, as are the other international partners.

The Boeing analysis is not yet complete and additional work will be needed to to show the lab can be safely operated beyond 2020. But Suffredini said no major surprises have cropped up so far and he's optimistic the station eventually can be cleared to fly through 2028 -- in theory, at least.

"When we get to 2028, the solar arrays are going to be struggling, I'm probably going to have a handful of radiator lines that have been isolated," he said. "2028 might be possible, but it also might be very challenging because then you're talking about the cost of replacing big things that may be prohibitive.

"All our analysis kind of says we think we can get to 2028 and that's the path we're headed on. As we start getting beyond 2028, if it makes sense, and things aren't failing at a rate that makes it difficult for us to keep up, and the country thinks it's the right thing to do, then we can look at going beyond that.

View original post here:

NASA looks to post-2020 International Space Station operations