Damien Broderick wrote:
>> They're on pp. 18, 60, 223, 254 (the last two being really
>>stupidly careless references to the `lenses' of the Hubble Space
>>Telescope - which is a refractive device, using mirrors).
>I thought the original mirror for the Hubble was ground
>incorrectly, and that it had to be repaired with corrective lenses
>to compensate. I heard this while working for a (nameless) client
>who temporarily feared that the Mirror error was caused by their
>computers. Later it was discovered that the error was due to
>other causes.
The Hubble repair used small corrective mirrors to fix the problem.
Brian
Member,Extropy Institute