I am definitely no scientist, so I couldn't figure out what was the point of having a rat in the lab. It was shown a few times but (at least I didn't notice) nothing was done with it, until its sad end. So what was his/her job there?
shareProbably just testing the effects of weightlessness.
https://www.space.com/26877-rats-in-space-nasa-experiment.html
I think it was probably being used as a canary, checking to see if it was safe for human life to be in the pod. Totally overkill and was just there to provide that one scene.
shareTo find out how long it takes for a laboratory in a weightless environment to have every surface coated in rat faeces and urine, obviously.
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