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Re: [Fwd: starship-design: HIGHLY OPTIMIZED TOLERANCE]

KellySt@aol.com writes:
 > Hate to tell you, but the Star Trek like tech would be to crude for a couple 
 > decades from now, and a IC chip is a IC chip.  So using and old CPU is not 
 > going to bye you anything.  

When it comes to space applications, not all ICs are equivalent.
There's a reason spacecraft don't use off-the-shelf Pentiums or
whatever; most processors designed for terrestrial use aren't
radiation-resistant and aren't capable of enduring thermal extremes, as
well as being overkill for many control applications.  Galileo, launched
in the 80s, uses 1802 microprocessors from the early 70s, and so do many
other probes of its generation.  Even with the 1802's CMOS design,
Galileo is experiencing frequent computer resets whenever it makes close
passes to Jupiter and its radiation belts.  The Hubble Space Telescope's
recent computer upgrade got it up to using space-certified 486s.  You
should note that the Mars Pathfinder lander, which used a relatively
modern IBM RS/6000 processor, failed after 90 days, most likely due to
daily thermal cycling between cold and really damn cold.  The rover used
a CMOS 8085 that probably lasted quite a bit longer.