Besides launching new hardware, what major task related to sustaining a long-term orbiting laboratory does NASA continue to manage?

Answer

Managing and operating the International Space Station (ISS)

NASA continues to manage and operate the International Space Station, which involves monumental engineering and on-orbit maintenance, rather than focusing solely on launching new hardware.

Besides launching new hardware, what major task related to sustaining a long-term orbiting laboratory does NASA continue to manage?
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