Comment by sholladay

It annoys me that there wasn't even a mention of the mere possibility that we may have contaminated the planet with the microbes in question. Sterilizing complex machinery is difficult and absolute sterilization of spacecraft has never been a goal of any space agency. Then we find out the microbes are probably in an area where one of our rovers has been exploring for a few years and you have to wonder. Granted, it does seem unlikely, and perhaps the microbes are indeed under the ice and have been since before we got there. But it seems irresponsible to not even consider contamination as a potential cause when we can clearly connect the dots to how that could have happened.