Re: ATM (Test)Plate mirror warnings

[Mike Coslo <mjc5@psu.edu>]

	Aside from all the strange controversy this thread has brewed, the
original experiment remains valid. This experiment is testing the
hypothesis that a plate glass mirror is subtly sensitive to mechanical
shock, changing figure after being struck. I proposed applying
mechanical stress to a spherical mirror in the form of striking it with
a blunt instrument of resilient material, the material chosen to to
lessen the likelyhood of catastrophic failure. A comparison between pre
and post shock would be made. This would be only one condition, but if a
difference was observed, more experiments could be done. Perhaps on
mirrors that are poorly annealed.

	We hear about stress induced figure changes from time to time. Why not
try to find out if there is any truth to them? Otherwise we are just
repeating things that there isn't really any proof for.

	I wouldn't suggest abusing one's telescope mirror this way, only a
mirror specifically made for this purpose.

	- Mike -

	

"Day, Jack" wrote:

>      Please do not to hit your mirror with anything unless it really
>      is due to a stuck lap or tool.  And then use extreme caution.  It
>      is  sad  when bad things sometimes happen to good people.