The GMT has 7 mirrors, each 8m wide. The 30m Telescope has one 30m mirror, plus a 3m secondary mirror.
I'm not sure which would be optically better, but I'd guess that the GMT will have more uptime as you can remove a mirror for cleaning without taking down the entire telescope.
I'm sure one of the first things that you think of when using big pieces of glass is the fact that they'll get dirty. A little bit of googling tells us that the mirrors will be regularly CO2 -cleaned, (basically blasting all dirt off the surface of the mirror) - see section 10.11:
http://www.gmto.org/science-conceptu.html . Each mirror will also get recoated every 2 years, to prevent scratches and blemishes.
Can't seem to access the PDF link to read more into it.
Interesting that the (sometimes) hours of effort involved in derailing a message thread or debate only pays 50 cents - one might argue that you'd be looking at 50-100 threads at once, but surely that's still not enough to justify the hours of work that must go into it each day?
Slashdot Mirror
Broke it. Does that mean it's safe now? http://www.google.com/404
The GMT has 7 mirrors, each 8m wide. The 30m Telescope has one 30m mirror, plus a 3m secondary mirror. I'm not sure which would be optically better, but I'd guess that the GMT will have more uptime as you can remove a mirror for cleaning without taking down the entire telescope.
I'm sure one of the first things that you think of when using big pieces of glass is the fact that they'll get dirty. A little bit of googling tells us that the mirrors will be regularly CO2 -cleaned, (basically blasting all dirt off the surface of the mirror) - see section 10.11: http://www.gmto.org/science-conceptu.html . Each mirror will also get recoated every 2 years, to prevent scratches and blemishes.
Can't seem to access the PDF link to read more into it. Interesting that the (sometimes) hours of effort involved in derailing a message thread or debate only pays 50 cents - one might argue that you'd be looking at 50-100 threads at once, but surely that's still not enough to justify the hours of work that must go into it each day?