Answer: An Intel 486

While consumers clamor to get their hands on the best and newest hardware, when it comes to designing systems for the rigors of deep space, NASA takes a more conservative approach. Hardware used in NASA designed rockets, shuttles, and satellites is selected based on stability and longevity, not necessarily on speed or cutting edge technology.

A perfect example of this is how dated the Hubble Space Telescope’s primary computer system is (both in context of the time it was launched and relative to technology today). When the Hubble was launched in 1990, the primary computer on board was a 1.25 Mhz DF-224 system built by Rockwell Autonetics. During the first service mission in 1993, astronauts added in a co-processing unit which consisted of two redundant strings of an Intel-based 80386 processor with an 80387 math co-processor. In 1999, during service mission 3A, astronauts replaced the entire primary computer with a 25 MHz Intel-based 80486 processor system.

For a frame of reference, in relation to the consumer market at the time (1999), the first Intel Pentium III variant “Katmai” was dominating the consumer market and was capable of maxing out at 600 Mhz.