"Stanislaw Sidor" wrote:

I was wondering why NASA accepts a shortened life for the Mars
Rovers
due to "dust build-up on the solar panels".

I don't think cleaning them is "beyond" the engineers, but it may
be a case of diminishing returns (I was really hoping for someone with
direct knowledge to answer... Geoffery Landis?). Keep in mind a lot of
that "dust" is about the size of smoke particles, which you''ll have
trouble just "wiping off". Electrostatic solutions might be
troublesome on silicon cells.

This is the most stupidity in space exploration when a ground probe's
lifetime is limited to 2-3 months

Or, it's ecomonics. Viking, which did a wonderful job (well beyond
design specs), also was a lot more expensive than a MER-class mission,
involving things like Titan launch vehicles (not the less expensive
Delta). As another point, extending the mission to the year+ timespan
would involve a lot of hardware modification/certification, well
beyond just using a longer-term power source.

Why? Because plutonium Pu238 is bad?

Hardly. An RTG-powered rover is in the works for a future mission
with a life time of a year or so. But it will be a lot more expensive,
and will not use an airbag landing system (there are limits to that as
well).

A good science is to send a probe which is able to work all 5 years!

Sure. Good science would be to put hundreds of trained geologist on
the surface of Mars, with equipment to traverse the surface. But
economicly, there *might* be some constraints here.

--
Brian Davis