Nasa faces contamination dilemma over Mars water investigations | Science | The Guardian
http://www.theguardian.com/science/2015 ... sity-rover

I wonder what the extra cost would have been for sending up a sterile rover in the first instance over the next mission. And even that's not taking into consideration the timeframes and mind-boggling logistics.

I wonder how much work it actually is to sterilise something that's going to be exposed to the hard radiation in space for months at the very least. I know bacteria can be tenacious little blighters but still...