From: kysy@erikseen.com.retro.com   
      
   >    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.   
      
   >From watching all NASA webcast lectures (tens of them), the message has   
   been (questions answered by the main scientists themselves) that there is   
   no way  currently to prolong the solar panel longevity with any cleaning   
   methods. Of course you can clean your summer shack solar panels because   
   you do not have the absolute and strict limitations of distant space   
   rover. Simply dry wiping the panels you would prolly do more damage to   
   them than good.   
      
   There is lots of other things that lessen the lifespan of rover, one of   
   the absolutely unpassable (with solar panels that is) obstacle is the   
   Mars winter, no sun no power. The electronics will break up when they   
   cannot be kept in stable warmth with electricity.   
      
   But, from what ive seen in those lectures, they are now starting to   
   really develope rovers that utilize plutonium power. Seems like atomic   
   hysteria is somewhat over. But even those do not last for years, theyre   
   just too small and filled with super high tech components that cannot be   
   eventually protected by the temperature changes which will be very   
   dramatic on winter. You just can begin to compare Viking landers and   
   these things, its like saying that why does paper burn when rock doesent.   
      
   >    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,   
      
   Plutonium power, i think, will be a lot cheaper than the high tech solar   
   panel arrays. Its because the Pu -> electricity is very simple design (by   
   space tech standards).   
      
   >    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).   
      
   I remember them saying something like 9 months of operation. One big   
   benefit, besides the lifespan is that such rover can move much much   
   faster (more amps available) and thus move farther, even hundreds of   
   kilometers.   
      
   It will be helluva bigger machine (size of small car), i think that   
   restricts the landing to rocket propelled lander. Which means lots of   
   additional fuel kg:s -> lots of $$.   
      
   >    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.   
      
   I dont believe that Mars surface will ever be accessed by humans, robots   
   can stand the super harsh evinroment (solar winds etc.) better. In 2050   
   the robots will prolly be better geologists than humans..:) If there is   
   anything worthwhile of sending more robots in the distant future.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)