James Webb Telescope: How to keep a $10 billion instrument 100 percent clean - Interesting Engineering

Before it launched, an entire team of engineers had to work around the clock to keep every surface of the magnificent James Webb Telescope 100 percent clean.

The more sensitive the instrument, the harder it is to keep clean.  Essentially, this was the case for the James Webb Space Telescope while it awaited launch late last year, after it arrived at Aria… [+4649 chars]

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