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The Teflon coating on the Hubble Space Telescope’s outer casing is cracking
up. NASA didn’t expect to see a problem for 10 to 15 years, but cracks began to
show on the thermal protection material in 1993, just three years after the
launch. In tests at NASA’s Glenn Research Center in Ohio, Kim de Groh found out
why: radiation makes Teflon brittle, leaving it less able to withstand the hot
and cold extremes of space (High Performance Polymers, vol 13, p 401).
De Groh hopes a February 2002 shuttle mission will apply fresh Teflon and a new
woven polymer fabric designed to stop further cracks spreading.