i have also reinstated this statement which they removed from the first para the need for planetary protection measures is strongest for missions designed to return a sample from another planet or celestial body to the earth back contamination again without discussion the sentence was not written by me it could perhaps do with a cn what source actually says this and if the reader wants to follow it up further what did they say exactly personally i think forward contamination is also pretty important but certainly not removed without discussion like this the rest is merged material from other articles and as i don't think they belong here i don't want to get involved in editing those sections the history section was originally much shorter and immediately after the intro and i don't see the point in the resilience of life in space section wouldn't put that as the first or indeed any section in an article on planetary protection i would just revert the entire thing back to the way it was before wp and bi edited it if it was up to me