QUESTION:
How do you protect the Pathfinder's computer against radiation? Is there an
upper limit for protection against cosmic rays?

ANSWER from Donna Shirley on December 11, 1997:
There are many ways.  First of all, the electronic parts are made out of
material which is resistant to damage by radiation.  Second, the software is
designed to recover from "bit flips" caused by transient radiation problems.
In some cases, the rover modem for instance, the software turns off and on
the hardware periodically so that it can recover if it has been affected by
radiation.

Donna Shirley