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Accumulated environmental damage to Hubble main mirror

  1. Dec 11, 2014 #1
    I'm interested in understanding what effect does long-term radiation and microdust exposure would do to the surface roughness of a high-precision mirror like the one on the Hubble. Since it has been on orbit for 24 years, it provides an unique opportunity to estimate accumulated environmental damage to high-quality mirror surfaces in general.

    Since surface roughness is directly related to scattering losses and Strehl ratio, I figure that a measurable decay of image quality and total luminosity would enable an estimate of this.

    Do astronomers working on the Hubble track for optical degradation of the optics? if yes, what techniques do they use? what fraction of that degradation is actually related to mirror degradation?
  2. jcsd
  3. Dec 11, 2014 #2


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    Staff: Mentor

    From here: http://www.spacetelescope.org/about/faq/
    Also, from here: http://www.nap.edu/openbook.php?record_id=11169&page=12

    From these two sources, I'd say no, there is no measurable degradation of the mirrors.
  4. Dec 14, 2014 #3


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    It would be splendid if the Hubble could be retrieved when it is finally retired, It would not only look splendid in the Smithsonian, but, I expect engineers would have a field day assessing and understanding material effects [or lack thereof] of long term exposure in low earth orbit. Perhaps we could boost it to a more permanent orbit until retrieval became feasible. It would be a shame to turn it into a funeral pyre crashing back to earth.
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