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@REPLYADDR RichA <rander3128@gmail.com>
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On Saturday, 16 September 2023 at 07:59:48 UTC-4, Quadibloc wrote:
> On Saturday, September 16, 2023 at 4:34:03 AM UTC-6, RichA wrote:
> >
https://phys.org/news/2023-09-large-space-telescopes.html
>
> Up until now, space telescopes didn`t use adaptive optics.
>
> The article claims that if a space telescope were launched with a 6.5
> metre mirror made from a single borosilicate glass blank, though, it
> would be needed. Since there`s no atmosphere to worry about, I suppose
> the culprit is thermal expansion of the mirror itself.
>
> John Savard
Changes to Beryllium (what the Webb has) with temperature are
probably more than borosilicate glass. But the Webb has its heat shield.
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