After months of preparation and screening, four specially trained mice - two males and two females - are set to become the first small mammals to enter China's space station.
They will travel aboard the Shenzhou-21 crewed spacecraft on Friday to take part in a pioneering experiment on how living organisms adapt to the challenges of space.
The experiment, titled "Space Animal Strain Screening and Feeding Key Technology Verification," will investigate how small mammals respond to microgravity and other conditions in orbit. For five to seven days, the four mice will live inside a specially designed module on the China Space Station, while scientists monitor their behavior, health, and stress responses in real-time.
The four mice were chosen from a pool of about 300 candidates after more than two months of testing and training. Researchers at the Institute of Zoology, Chinese Academy of Sciences, meticulously evaluated each mouse's physical fitness, reproductive capacity, agility, memory, and spatial awareness.
"We finally selected 48 as backup mice before launch from about 300 mice. In the end, only four mice - two males and two females - will officially go to space. In each round of screening, we eliminated about 10 to 20 percent of the mice," said Wang Yixi, engineer from Laboratory Animal Center, Institute of Zoology, Chinese Academy of Sciences.
Once launched, the mice will travel in a life-support container specially built to protect them during the journey from Earth to orbit. Upon arrival, astronauts will transfer the experimental unit to a dedicated feeding device aboard the space station, where the mice will continue their stay in carefully controlled conditions.
"All the devices are designed to provide suitable living and protection conditions for the mice. The mice are placed in an experimental unit, which is then put into a life-support device during the launch and ascent phase. This ensures that the mice have stable life-support conditions throughout the journey from the ground to the space station. Once in orbit, the experimental unit is removed from the launch life-support device and placed into our feeding device, which provides an even better living environment. During feeding, cameras are used, and we can observe the mice's daily activities and overall state in real time from the ground monitoring hall," said Liu Fangwu, associate researcher from Shanghai Institute of Technical Physics, Chinese Academy of Sciences.
Four mice selected to join China's upcoming Shenzhou-21 space mission
