https://en.wikipedia.org/wiki/Ingenuity_(helicopter)

It was sent to Mars with a plan for 5 flights and a total of 7 or 8 minutes flight time. It ended up flying for over 2 hours in 72 seperate flights before it damaged itself with a bad landing. Not quite the "this thing is still doing science almost 50 years later" that Voyager can claim, but impressively engineered so it lasted way beyond it's initial mission plan.

Curiosity was intended to operate from 2011-2013 and is still active now, just shy of 5000 days after landing. Really impressive.