I realize that it will be at least 3-5 years before Hubble's instruments and guidance gyros will fail to the point of making it unusable. Many people feel that it is no more dangerous to send the shuttle back to Hubble for it's last servicing mission than to send it up to the International Space Station to finish it's job of construction there.
There may also be ways to perform that servicing mission with the robotic mission. Simply saying that we need to send up a propulsion module to de-orbit Hubble when it becomes unusable is giving up without looking for other alternatives.
Given the nature of how past mission objectives have usually been years behind in their intended schedules, it is probable that the James Webb NGST (Next Generation Space Telescope) will not be in place for its intended mission to replace Hubble Space Telescope as it is currently planned for around 2015 at the earliest.
Is there anyone who agrees that an all-out effort should be made to service Hubble one last time to make the time gap between how long Hubble can last versus when we can launch the James Webb Space Telescope as small as possible?
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