Planetary protection is not just a matter of science. It is also a matter of value. This is so independently of whether we only include the protection of science or if we also include other goals. Excluding other values than the protection of science is thus a value statement, not a scientific statement and it does not make planetary protection value neutral. It just makes the axiological basis (that is, the value basis) for planetary protection more limited in a way (...) that is inconsistent with the axiological grounds for back contamination, ethically questionable and strategically unwise. However we look at it, we cannot get away from the conclusion that the axiological dimension of planetary protection is a task that needs to involve experts on value theory as well as experts from a range of different sciences and also include opinions from outside the academic community. (shrink)