Ohh I thought you meant the RAT as in Rock Abrasion Tool aboard the Mars rovers Spirit and Opportunity!! 5 yeas they have been on Mars and still counting, one has a dead wheel and has to drive backwards, the other has a problem with one of its robotic arm joints so cannot stow it but other than that, a bit of dust on the solar arrays and a wheel on Spirit showing early signs of wear they are in good health!