Pioneer 10 Still Running After 30 years
evilempireinc writes "According to this article in Scientific American, Pioneer 10 is still functioning 30 years after it was launched in 1972, and is still sending back scientific data. The article mentions that two other old space craft, Voyager, and IMP-8 are still functioning after over 20 years as well due to overbuilt construction and redundant systems. Can't help but wonder if the present generation of "faster, better, cheaper" probes will ever live this long though."
Most of these cheap probes are meant for suicide missions. It's hard to keep sending back info when you're slamming into a hellish atmosphere, or weathering the sandstorms of Mars.
It's like comparing dispisable watches to a Rolex.
No!
you don't want the probes to survive longer than planned. You want them to be like F1 race cars: ideally, the engine should explode _just_ over the finish line. Only then have you maximized tolerances. However, due to uncertainty, you engineer in a margin of safety.
A 30 year margin doesn't indicate good design, it indicates a MASSIVE misjudgemnt of the tolerances involved. Fine. these were the first probes built, so noone knew the margins needed.
It's misguided to continue insisting on such ludicrous margins. If you want a long-living probe, then that becomes a design consideration, but this _moves the finish line_, rather than increasing the margins necessary.
The long life of the probes is indicative of good engineers making conservative choices in the face of uncertainty rather than good design.
aside:
the only reason why fast-cheap-cheerful isn't a handsdown winner is that each probe's cost is augmented by the cost of launch, which makes even a free probe an expensive mission. Thus, there is economic gain from a bit of overengineering, as the cost of the hardware isn't really a large part of the total cost, so any bonus functionality you get is worth the price, to a limit.
The real loss if the ISS is shut down will be that they could have built a rail-gun to fire largely unpowered probes on long-term missions for basically free.