Some contamination is unavoidable, but we want to minimize it at least in the beginning, just in case those samples from 50 years ago that might have revealed the presence of life that we killed, were actually samples that revealed the presence of life that we killed:
Some contamination is unavoidable, but we want to minimize it at least in the beginning, just in case those samples from 50 years ago that might have revealed the presence of life that we killed, were actually samples that revealed the presence of life that we killed:
https://bigthink.com/hard-science/accidentally-killed-life-mars/