Perseverance made it to Mars on twenty-year-old hardware

I’m a space junkie. So tonight, like all the other space junkies on the planet, I watched in awe as Perseverance seamlessly and beautifully landed on the surface of Mars. This is a phenomenal achievement. Of course, I will eagerly follow her1 progress.

As I was following the live broadcast, I wondered: What kind of hardware and software runs all this incredible technology? It was launched in 2020, so it must be some cutting-edge stuff. As it turns out, that isn’t really the case.

Perseverance computer uses the BAE RAD750 radiation-hardened single board computer2. Released twenty years ago (2001), the RAD750 is based on the PowerPC 750, designed by IBM and Motorola and released in 19973. The exact same computer is mounted on Curiosity4, which launched ten years ago.

It basically has the power of a circa 1992 Pentium 1 chip and will be responsible for handling the entire avionics architecture of the rover designed and programmed by NASA’s Jet Propulsion Laboratory (JPL) (source)

From the same source, we learn that at least good-ole RAD750 is not left alone:

The ‘old school’ RDA750 computer will work in tandem with a series of field-programmable gate array (FPGA) computers to control such things as the drivetrain, wheels, suspension and cameras.

I could not find any reliable information on the programming languages involved. I am guessing a mix of C/C++ and maybe Ada, as is typical of the aerospace industry. The operating system itself is VxWorks5, a real-time operating system initially released in 1987. This is a fascinating piece of software.

Two considerations come to mind. First, and I am repeating myself here, what a phenomenal achievement this landing is. As we watched the broadcast, I told my wife: these guys are literally making the future of humanity. What did I know that they’re making it on twenty-year-old technology. Second. We, ordinary people, might all be using way more power (and grid) than is really needed.

Originally posted on my website.

1

As a non-native speaker, I was surprised (and delighted) to note that they refer to the drone as ‘her’