From Richard Vellacott, Barnoldswick, Lancashire, UK
You published a timely article about preserving us from the possibility of being wiped out by Martian microbes brought back to Earth in study samples. I hope sufficient steps are being taken to prevent Earth microbes from contaminating Mars and elsewhere that we visit (4 November, p 21).
It would be a tragedy to wipe out life forms before we even meet them, especially in the name of science. Am I right in thinking that a consignment of Earth tardigrades crashed onto the moon recently? Oops!
