Fantastic technology! This stuff is old, but it still works extraordinarily well. They sure knew how to engineer stuff then.
They say that they might keep going until 2020 -- I bet those bad boys will surprise us and keep on kicking for much longer!
Arguably, the current generation of engineers aren't too shabby themselves. Spirit and Opportunity were designed to last 90 sols, with their actual missions lasting some 25 times that, and Opportunity is still knocking about up there.
On a second thought, you're absolutely right. There's really no way I can tell what's good engineering or bad in present time until a few decades down the track.
From memory, the probes will shut down their functioning gradually as they run out of power. Also if they stop receiving messages from earth they will keep doing science according to some preprogrammed procedure and beam the results back. Go humans!
Plutonium 238 which powers the thermopiles has a half-life of about 87 years and many of their instruments are no longer in operation, so the remaining mission scope is an issue of power management.
Fantastic technology! This stuff is old, but it still works extraordinarily well. They sure knew how to engineer stuff then. They say that they might keep going until 2020 -- I bet those bad boys will surprise us and keep on kicking for much longer!