via MSNBC, the shuttle's Hubble Space Telescope repair mission has been moved out to next year due to a new unexpected issue with the orbital space observatory. The new issue is with the Hubble's communication array and prevents the observatory form sending any data it collects back to Earth. The astronauts training for the mission now must prepare for a possible replacement of the components of the command and data handling system. However, there is a plus, in that the issue arose before the launch, which allows NASA to work on a potential solution.
"It could have been far worse, said NASA’s science chief, Ed Weiler. “Think about if this failure had occurred two weeks after the servicing mission, we had just put two brand new instruments in and thought we extended the lifetime for five, 10 years and this thing failed after the last shuttle mission to Hubble,” Weiler told reporters Monday evening. “So in some sense, if this had to happen, it couldn’t have happened at a better time.”
In the meantime, the space agency will attempt to switch to the telescope's backup systems, which have not been turned on since before its original launch date almost twnty years ago. Another issue could be with the replacement part the agancy has on hand - the part was last tested in 2001, and it will take until January to test and certify it for use. This delays the launch of the mission until February at minimum.
The mission already had an ambitious set of goals: the addition of two new instruments, the replacement of batteries and gyroscopes, and the repair of two other instruments. However, the fix to the array is relativley simple and would not entail a separate spacewalk over the planned five for the mission, but most likely extend one spacewalk for a period of around two hours.