[X] My Assistant

[algorithm]

All in all the MSL wheels have done pretty well.

IMHO, that's a pretty low expectation. Personally I wouldn't bolt on a nuclear generator just to enable a rover to last the lifetime of a wheel, especially if that wheel did 'pretty well' to last two years.

[mcaplinger]

Personally I wouldn't bolt on a nuclear generator just to enable a rover to last the lifetime of a wheel...

Without some kind of active solar panel cleaning, which we don't know how to do in a practical and flight-qualified way, there is simply no way to guarantee even two years of mission life on Mars without an RTG. The MERs got lucky with cleaning events.

MSL was designed to last two years, which means in general that it was life-tested for four years. Anything past that is gravy.

That said, it's been stated that the degree of wheel damage was unexpected. Hindsight is 20/20.

[RoverDriver]

Mike, we had a global storm in the Summer of 2007 and both MERs survived it. I thin tau went up to 5 and beyond.

Paolo

[mcaplinger]

Mike, we had a global storm in the Summer of 2007 and both MERs survived it.

You're right, though we could have a discussion about the definition of a global dust storm versus a planet-encircling dust event, etc. At any rate the 2001 storm was much more severe than the 2007 one and current thinking is that these are somewhat random and hard to forecast. I think that the 2001 storm would have killed the MERs almost certainly.

It's an interesting question as to how long a solar-powered lander would be claimed to last at this point and whether MER experience could be used to lengthen that beyond a few months. I'm skeptical that the MER experience could be banked on.

[This discussion is off-topic for this thread but I think there's some new and interesting points being made, so perhaps the mods could move these items elsewhere if they wish.]