RE: ATM Stellafane

["Good, Donald" <dgood@aha.org>]

'Nuf said about the weather.  An interesting talk was given by Dr. Peter
Chan about his work in developing optical quality composite mirrors.  The
problem is to find the right materials that remain stable to optical
tolerances (e.g. no swelling due to moisture absorption into the resin) in
its intended operating environment (space or terrestrial).  He claims to
have achieved diffraction limited quality from vacuum bagging a honeycomb
composite structure over a mandrel (mold) that can be repeated about 50
times on the same mandrel.

He showed a very fast (< F2 ?) uncoated mirror about 30" diameter that
weighed 13 pounds.  A comparable glass mirror would have weighed 400 pounds.
A truss tube with 3 point mirror cell (only needed 3 point support) was
light enough to lift with one finger.

If memory serves me, his NASA url is:
http://snoopy.gsfc.nasa.gov/~lunartel

However, access to internal NASA sites is temporarily blocked due to the
Code Red Worm.  See notice at 
http://www.gsfc.nasa.gov

Clear skies
Don

-----Original Message-----
From: Guy Brandenburg [mailto:gfbranden@earthlink.net]
Sent: Monday, August 20, 2001 11:04 AM
To: atm@shore.net; novac@his.com; capitalastronomers@yahoogroups.com
Subject: ATM Stellafane



Would anybody who attended Stellafane care to tell the rest of us
something about how it went? Was the weather decent or rainy? What sort
of interesting telescope ideas and concepts were there? And so on.

Guy Brandenburg