Reply #20: it's not NASA's choice, it's Bush's choice

[rman]

(and it's not NASA's fault that they're on a tight budget)

Hubble casualty of Bush space plan

http://www.cnn.com/2004/TECH/space/01/16/hubble.telescope.ap/
...
He said the decision was influenced by President Bush's new space initiative, which calls for NASA to start developing the spacecraft and equipment for voyages to the moon and later to Mars. The president's plan also called for the space shuttle to be retired by 2010. Virtually all of the shuttle's remaining flights would be used to complete construction of the International Space Station.
...

(of course it is NASA's fault that management 'solved' the budget issue by firing the engineers, and now subcontract pretty much everything - but that's another story)