[jcoc611]

> The presence of terrestrial microorganism within a sample of Ryugu underlines that microorganisms are the world's greatest colonizers and adept at circumventing contamination controls. The presence of microorganisms within space-returned samples, even those subject to stringent contamination controls is, therefore, not necessarily evidence of an extraterrestrial origin.

Basically that preventing terrestrial contamination of extraterrestrial samples is super tough, and in the specific case of Ryugu the study concludes that contamination did occur.

[hn_throwaway_99]

I recall a study from a few years ago that showed that Acinetobacter bacteria can eat the detergents that NASA used to clean spacecraft to prevent contamination: https://www.theatlantic.com/science/archive/2018/06/bacteria...