Are there any places (Moon, Mercury, etc.) in the solar system which we can be certain, beyond reasonable doubt, do not contain life? If so, what is the reasoning behind sterilization of probes and landers in these areas? Isn’t it our prerogative and obligation to attempt to introduce extremophiles to such environments for research and to gain actual experience in terraforming, which many view as inevitable & necessary?
Yes, I agree that there is no life on the Moon or Mercury. Such destinations are not subject to planetary protection restrictions, and probes sent to these planets do not require sterilization. However, the Moon can serve as a laboratory for testing sterilization techniques that might be applied to spacecraft sent to Mars. As far as introducing extremophiles to places like Moon and Mercury, that would be pointless if these planets are truly unable to support Earth-based life. Ironically, the only tragets (such as Mars and Europa) where we might want to undertake experiments introducing microorganisms from the Earth are precisely the ones where we should not do so, since these objects may have indigeonous biota that we should not disturb. From a practical perspective,, also if we one introduced microbes from Earth into those environments, we might never be able to distinguish native life we had introduced.
NLSI Interim Director
September 25, 2007