I did not know that cleanrooms have classes. Apparently they used a 10000 class cleanroom which is one of the "dirtiest" grade.

Surely an astroid sample return mission is scientifically one of the most important and difficult things to accomplish, and I wonder why they did not use a higher class cleanroom for this even though they mentioned "Researchers recommend enhanced contamination control procedures for future sample-return missions to prevent microbial colonization and ensure the integrity of extraterrestrial samples."

Related? https://news.ycombinator.com/item?id=42244003 - We can mine asteroids for space food

So we are the ones potentially spreading life by accident. Fascinating! Now if Ryugu hits a distant body we could perhaps have proven our own panspermia hypothesis! What a time to be alive.

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