This presupposes there are cats on Mars, which seems unlikely. In any case, Curiosity could zap the aforementioned felines with its powerful laser, and quickly work its way through them.
What on earth am I talking about? I'm talking about the Curiosity rover, arguably the most advanced robot ever and certainly the most ambitious mars program to date. The cats are my idea of a pun, possibly not a good one.
Curiosity is the size of a small SUV, powered by a nuclear reactor, armed with a powerful laser, and peering out with very advanced sensors. It is designed, not to look for life itself, but to look for places that may once have harbored life.
Curiosity will examine sediments and geologic formations for signs of organics. It will fry a rock formation with its laser, vaporizing a small part of it. On-board detectors will look at the gas cloud and determine the composition. Other sensors will take data about the atmosphere, and scan the ground for signs of life. Cameras will send images back to Earth.
The target for Curiosity is Gale Crater. What makes this crater unique is the large mound in its center. Geologists believe this mound is made of sediments from all the eras of Mars. With luck, the entire geological record of Mars is contained within this single formation. That way, Curiosity can examine the whole history of Mars in one go.
It will take about a month for Curiosity to land. It must survive a searing descent through the atmosphere, deploy a supersonic parachute, fire its retro rockets, and finally be lowered to the ground by a rocket powered, hovering sky-crane. Nothing this ambitious has been attempted in space exploration, and many hundreds of millions of dollars are riding on it.