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View Full Version : Discussion: Keck Uses Adaptive Optics for the ...



Fraser
2003-Oct-08, 07:48 PM
SUMMARY: The 10-metre Keck II observatory took an important step forward recently when it began observations with its new adaptive optics system. The system uses a laser to create a fake star about 90 kilometres up in the sky - a computer can then use this to calculate how to remove the effect of atmospheric disturbances. Adaptive optics have been used on smaller telescopes, but this is the first time it's been employed on a telescope as large as the mighty Keck II; it took nine years to adapt the observatory.


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Matthew
2003-Oct-09, 10:00 AM
Why would it take 9 years to adapt the observatories. Wouldn't all you be doing is having a laser create the fake star and then focus the 2 telescopes onto it then calculate how to remove the effects of the atmosphere? Or is there something more to the process?

johnsowe
2003-Oct-09, 02:35 PM
:o :)

remcook
2003-Oct-09, 04:59 PM
To counter the effect of atmospheric disturbances, a mirror has to be deformed very precisely.

"The deformable mirror, about six inches (15 cm) in diameter, is made out of a thin sheet of reflective glass controlled by 349 actuators that can adjust the shape of the mirror by several microns, a distance large enough to correct for atmospheric distortions. "

from:
http://www.ifa.hawaii.edu/tops/keck02.html

"installed in 1999"!

so you have to install, re-allign, callibrate, all that sort of things.



some results:
http://www.spaceref.com/news/viewpr.html?pid=12473