It is able to live and grow even in very cold, hot or airless places. But it's not a scary alien from a movie. No, the life forms hiding out on the Space Station are very tiny microbes such as bacteria, fungus and virus. Microbes were the first things to live on the Space Station. They came from Earth, carried there on parts of the Station and on the crews who assembled the Station.
Microbes go anywhere that humans go.
Most are good, and some kinds help people. But some microbes could make the Station crew sick, and even attack the walls and machines on the Station. NASA works hard to find ways to keep these germs and other microbes under control. These are E. Coli bacteria magnified 5000 times. It lives harmlessly in human intestines and gives us vitamin K and some B vitamins.