Space qualified processors are very expensive to develop and produce. They are optimized for use in space and manufactured on an entirely different process than

Space qualified processors are very expensive to develop and produce. They are optimized for use in space and manufactured on an entirely different process than commercial chips. All of this is to ensure reliability in the harsh environment of space. Due to these development and fabrication costs, it's worth it to keep using the same processor as long as it is capable of doing the needed computations. The current RAD750[0] has been used since 2005 and will likely continue to be used for some time. [0] https://en.wikipedia.org/wiki/RAD750 https://en.wikipedia.org/wiki/RAD750