Bacterial origin.
In 2008, NASA conducted a bacteriological survey on the space station, and the results showed that there were a lot of bacteria here, but they were harmless, so people didn't pay much attention to them.
NASA considers these bacteria to be just remnants of the spacecraft and that there are not many of them, so they do not pose a threat.
But in 2011, NASA carried out a bacterial purge on the space station, and what was really surprising was that NASA cleaned the original few bacteria, and in a period of time after cleaning, the number of bacteria greatly exceeded the original number, and finally the number of bacteria reached more than 100 species, and the number of bacteria is still exploding upward.
Over time, the number of bacteria finally became so large that even astronauts could not tolerate it.
After they went on a space mission, everyone showed symptoms of varying degrees.
Many people have suffered from colds, coughs and other diseases, and many others have experienced symptoms such as diarrhea.
This proves that bacteria are harmful to the human body.
NASA was surprised to know why these bacteria had grown to such an extent on their own.
They cleaned the station once again and investigated the bacteria.
It turned out that these bacteria did not float from Earth into space, but were always present on the space station.
NASA conducted another inspection of the space station and finally discovered the cause of the growth of bacteria.
It turns out that the spacecraft is manned in space, so it will carry some bacteria left in the space station.
And there is no environment for bacteria to grow in space, so bacteria are received in the space station all the time.
Bacteria on Earth multiply where there is water, so there are no bacteria living on the space station in the first place.
In addition, the oxygen on the space station is constantly updated by the machines that produce it, so that the bacteria are inhibited by the bactericidal substances in the oxygen.
Therefore, when NASA conducted a bacteriological survey earlier, it did not mean that there were no bacteria, but that when these bacteria were discovered, the number was not large, and they were relatively scattered, so they would not pose a threat to the health of astronauts.
But after more than ten years of operation of the space station, the number of bacteria has become more and more, and the number of bacteria has formed a balanced relationship between these bacteria living in the space station, so the number of bacteria no longer increases by multiples such as 1 or 2 times.
But this growth method means that the number is no longer doubling as before, and it does not mean that the number of bacteria will not grow.
NASA didn't pay much attention to this problem, and if one day the number of bacteria really increased, they would still find a way to clean it.
But the number of bacteria continued to grow, eventually increasing by a hundredfold at once.
NASA analyzed the bacteria and found that these bacteria not only had a new source of food on the space station, but also a new breeding target, so the number of bacteria in this environment would increase significantly.
Why do bacteria multiply in large numbers in the space station.
There are a lot of bacteria living in the space station, so what will be in the space station to attract the growth of bacteria?
So these reasons are for the bacteria in the space station to multiply in the space station without anyone noticing.
These bacteria will survive on the space station and will be transmitted into space.
There are not only more than 100 species of bacteria on the space station, but thousands, but NASA did not investigate all the bacteria.
This number alone is enough proof of how large the number of bacteria is.
And these bacteria will continue to be transmitted to space, because there is no gravity in the universe, so the bacteria in the space station will be transmitted to space with the operation of the space station.
Not only that, but if any bacteria left on animals or passengers multiply on the space station, they can be carried to other planets.
Eventually, when astronauts go to other planets, the bacteria in the space station will be carried to other planets and multiply, eventually filling the entire planet with bacteria.
Causes of bacteria that are difficult to clean.
Doctors check the astronauts' health once a week, so the doctors immediately checked the number of bacteria and found that the number of bacteria was well beyond the normal range.
So not only will these bacteria not go down, but they will continue to rise, and they will continue to spread.
Why do these bacteria produce so many inert bacteria?
This is because water droplets are easily "shut down" by bacteria, so some inert bacteria are produced in these bacteria, and these bacteria form a dormant state in the water.
epilogue
Therefore, NASA stopped working on the space station for half a month, and carried out a thorough cleaning of the space station through ventilation and renovation, and finally kept the space station within a reasonable range.
NASA conducted a survey of the bacteria and found that the cleaning did not eradicate the bacteria from the space station, only decreased in numbers.
Therefore, in the future, NASA will also investigate the bacteria on the space station, and will often clean the space station to prevent these bacteria from endangering the health of astronauts.