This SPACE.com piece details the options open at this point regarding the future of the Hubble Space Telescope. I posted here about the cancellation of the shuttle mission to bring the Hubble home at the end of the decade and the possibility that the one remaining service mission to the Hubble is in danger of being scrapped, as well. While that’s bad enough, the question remains of what to do, especially if the service mission (originally scheduled for next year) is indeed cancelled. If the Hubble is left to spiral into the atmosphere, some significant parts of it will almost certainly survive re-entry and hit the surface.
“In particular the massive primary mirror and its surrounding titanium main ring — the structural backbone of HST — will almost certainly impact the Earth,” a Goddard report obtained by SPACE.com notes. Moreover, a special reentry computer calculation done by NASA’s Johnson Space Center predicts a 1/700 probability of human casualty resulting from an uncontrolled Hubble reentry. The current NASA requirement is a probability of less than 1/10,000.
So that means there almost has to be one more service mission to attach some sort of rocket unit, either to boost the Hubble into a permanent safe orbit, or to bring it down at a time and place of NASA’s choosing. If that’s the plan, why not perform other duties while up there to allow the Hubble to continue operating for an extended period?
Who knows? If we can stretch the Hubble’s life out long enough, maybe we can get the Chinese manned program to help us out eventually. While they’re on their way to the moon, perhaps.