NASA’s Abandoned ISEE-3 Spacecraft To Fly Past Moon, IEEE Spectrum
“Although ISEE-3’s nitrogen leaked away, the spacecraft has shown incredible longevity otherwise. Its solar arrays draw more than 90 percent of the power they did in 1980–about 150 W–and the spacecraft’s 1970’s CMOS circuitry–which consists of 4000-series RCA state logic–is still largely functional. When it comes to the solar arrays, Wingo says, it’s possible that some low-temperature self-annealing process might have helped repair radiation damage.”