Planetary Protection Officer Catharine Conley
Those rules required sterilization of any part of Curiosity that will touch the surface of the planet, including the drill bits and all six of the rover's wheels. The precaution was taken to preserve the ability to explore water or ice — even if the chances of finding it were remote.
About 250,000 bacterial spores throughout Curiosity are assumed to have survived the landing, officials said
NON STERILE "DRILL BITS" contact water ?
Just this year, Andrew Schuerger, a plant pathologist and expert on the survival of terrestrial microorganisms under Martian conditions, found a bacterium species capable of growing in conditions present on the surface of Mars, including air pressure of just seven millibars. Air pressure on Earth is 1,017 millibars at sea level.
NASA UN ethical concern
Fear of microbial contamination of the Martian environment long ago moved NASA and a United Nations space advisory committee to divide the planet's surface into areas based on the probability of encountering ice and water. The group also recommended sterilizing spacecraft destined for areas with ice and water.
Contaminating another planet is an ethical concern for scientists
Drill bits on rover
could contaminate Mars