Not sure if this has been posted before, I cannot find it if it has been.
http://www.youtube.com/watch?v=gxp6aMhoT9U&eurl=
Mike
cleaning the 200" mirror
Started by mclemens, 10/25/2006 04:59AM
Posted 10/25/2006 04:59AM
Opening Post
Not sure if this has been posted before, I cannot find it if it has been.
http://www.youtube.com/watch?v=gxp6aMhoT9U&eurl=
Mike
Posted 10/25/2006 08:41AM
#1
Hello:
This reminds me of the video of Subaru's recoating, which is on a DVD. In the case of Subaru, there are a few scary moments, such as then the mirror is being lowered through the dome floor to the coating room floor (about 4 floors below) by the crane. At that moment, the whole mirror is hanging by a steel cable. After the mirror is washed and the aluminum is stripped, baking soda is spread over the mirror with big brooms (the kind janitors use to sweep hallways). The mirror is then inspected for damage, such as from falling wrenches (one which hit the mirror). During this time, people walk on the mirror surface in order to get a good look at it!
As much as these mirrors are pampered, they take some abuse. Many of the mirrors on Mauna Kea have had things dropped on them. The Subaru mirror had some glass pulled out of the back side by one of the hard points. The CFHT mirror had mercury leaking onto it. The IRTF mirror has about a 6"x4" chunk taken out of the mirror surface around the central hole (which is not in the light path...whew!). I'd bet most amateurs out there would be shocked to see how dirty some of these mirrors get before they are washed!
Cheers
Mike Connelley
This reminds me of the video of Subaru's recoating, which is on a DVD. In the case of Subaru, there are a few scary moments, such as then the mirror is being lowered through the dome floor to the coating room floor (about 4 floors below) by the crane. At that moment, the whole mirror is hanging by a steel cable. After the mirror is washed and the aluminum is stripped, baking soda is spread over the mirror with big brooms (the kind janitors use to sweep hallways). The mirror is then inspected for damage, such as from falling wrenches (one which hit the mirror). During this time, people walk on the mirror surface in order to get a good look at it!
As much as these mirrors are pampered, they take some abuse. Many of the mirrors on Mauna Kea have had things dropped on them. The Subaru mirror had some glass pulled out of the back side by one of the hard points. The CFHT mirror had mercury leaking onto it. The IRTF mirror has about a 6"x4" chunk taken out of the mirror surface around the central hole (which is not in the light path...whew!). I'd bet most amateurs out there would be shocked to see how dirty some of these mirrors get before they are washed!
Cheers
Mike Connelley
Posted 10/27/2006 04:16AM
| Edited 10/27/2006 04:17AM
#2
A very cool video. I would agree those guys have to be a little paranoid.
The "star" we look at tonight may have exploded millenniums ago. (To progress, we must discern what exists and what does not).
